Repository: robfig/cron
Branch: master
Commit: bc59245fe10e
Files: 19
Total size: 90.5 KB
Directory structure:
gitextract_s3rbtqli/
├── .gitignore
├── .travis.yml
├── LICENSE
├── README.md
├── chain.go
├── chain_test.go
├── constantdelay.go
├── constantdelay_test.go
├── cron.go
├── cron_test.go
├── doc.go
├── go.mod
├── logger.go
├── option.go
├── option_test.go
├── parser.go
├── parser_test.go
├── spec.go
└── spec_test.go
================================================
FILE CONTENTS
================================================
================================================
FILE: .gitignore
================================================
# Compiled Object files, Static and Dynamic libs (Shared Objects)
*.o
*.a
*.so
# Folders
_obj
_test
# Architecture specific extensions/prefixes
*.[568vq]
[568vq].out
*.cgo1.go
*.cgo2.c
_cgo_defun.c
_cgo_gotypes.go
_cgo_export.*
_testmain.go
*.exe
================================================
FILE: .travis.yml
================================================
language: go
================================================
FILE: LICENSE
================================================
Copyright (C) 2012 Rob Figueiredo
All Rights Reserved.
MIT LICENSE
Permission is hereby granted, free of charge, to any person obtaining a copy of
this software and associated documentation files (the "Software"), to deal in
the Software without restriction, including without limitation the rights to
use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
the Software, and to permit persons to whom the Software is furnished to do so,
subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
================================================
FILE: README.md
================================================
[](http://godoc.org/github.com/robfig/cron)
[](https://travis-ci.org/robfig/cron)
# cron
Cron V3 has been released!
To download the specific tagged release, run:
```bash
go get github.com/robfig/cron/v3@v3.0.0
```
Import it in your program as:
```go
import "github.com/robfig/cron/v3"
```
It requires Go 1.11 or later due to usage of Go Modules.
Refer to the documentation here:
http://godoc.org/github.com/robfig/cron
The rest of this document describes the the advances in v3 and a list of
breaking changes for users that wish to upgrade from an earlier version.
## Upgrading to v3 (June 2019)
cron v3 is a major upgrade to the library that addresses all outstanding bugs,
feature requests, and rough edges. It is based on a merge of master which
contains various fixes to issues found over the years and the v2 branch which
contains some backwards-incompatible features like the ability to remove cron
jobs. In addition, v3 adds support for Go Modules, cleans up rough edges like
the timezone support, and fixes a number of bugs.
New features:
- Support for Go modules. Callers must now import this library as
`github.com/robfig/cron/v3`, instead of `gopkg.in/...`
- Fixed bugs:
- 0f01e6b parser: fix combining of Dow and Dom (#70)
- dbf3220 adjust times when rolling the clock forward to handle non-existent midnight (#157)
- eeecf15 spec_test.go: ensure an error is returned on 0 increment (#144)
- 70971dc cron.Entries(): update request for snapshot to include a reply channel (#97)
- 1cba5e6 cron: fix: removing a job causes the next scheduled job to run too late (#206)
- Standard cron spec parsing by default (first field is "minute"), with an easy
way to opt into the seconds field (quartz-compatible). Although, note that the
year field (optional in Quartz) is not supported.
- Extensible, key/value logging via an interface that complies with
the https://github.com/go-logr/logr project.
- The new Chain & JobWrapper types allow you to install "interceptors" to add
cross-cutting behavior like the following:
- Recover any panics from jobs
- Delay a job's execution if the previous run hasn't completed yet
- Skip a job's execution if the previous run hasn't completed yet
- Log each job's invocations
- Notification when jobs are completed
It is backwards incompatible with both v1 and v2. These updates are required:
- The v1 branch accepted an optional seconds field at the beginning of the cron
spec. This is non-standard and has led to a lot of confusion. The new default
parser conforms to the standard as described by [the Cron wikipedia page].
UPDATING: To retain the old behavior, construct your Cron with a custom
parser:
```go
// Seconds field, required
cron.New(cron.WithSeconds())
// Seconds field, optional
cron.New(cron.WithParser(cron.NewParser(
cron.SecondOptional | cron.Minute | cron.Hour | cron.Dom | cron.Month | cron.Dow | cron.Descriptor,
)))
```
- The Cron type now accepts functional options on construction rather than the
previous ad-hoc behavior modification mechanisms (setting a field, calling a setter).
UPDATING: Code that sets Cron.ErrorLogger or calls Cron.SetLocation must be
updated to provide those values on construction.
- CRON_TZ is now the recommended way to specify the timezone of a single
schedule, which is sanctioned by the specification. The legacy "TZ=" prefix
will continue to be supported since it is unambiguous and easy to do so.
UPDATING: No update is required.
- By default, cron will no longer recover panics in jobs that it runs.
Recovering can be surprising (see issue #192) and seems to be at odds with
typical behavior of libraries. Relatedly, the `cron.WithPanicLogger` option
has been removed to accommodate the more general JobWrapper type.
UPDATING: To opt into panic recovery and configure the panic logger:
```go
cron.New(cron.WithChain(
cron.Recover(logger), // or use cron.DefaultLogger
))
```
- In adding support for https://github.com/go-logr/logr, `cron.WithVerboseLogger` was
removed, since it is duplicative with the leveled logging.
UPDATING: Callers should use `WithLogger` and specify a logger that does not
discard `Info` logs. For convenience, one is provided that wraps `*log.Logger`:
```go
cron.New(
cron.WithLogger(cron.VerbosePrintfLogger(logger)))
```
### Background - Cron spec format
There are two cron spec formats in common usage:
- The "standard" cron format, described on [the Cron wikipedia page] and used by
the cron Linux system utility.
- The cron format used by [the Quartz Scheduler], commonly used for scheduled
jobs in Java software
[the Cron wikipedia page]: https://en.wikipedia.org/wiki/Cron
[the Quartz Scheduler]: http://www.quartz-scheduler.org/documentation/quartz-2.3.0/tutorials/tutorial-lesson-06.html
The original version of this package included an optional "seconds" field, which
made it incompatible with both of these formats. Now, the "standard" format is
the default format accepted, and the Quartz format is opt-in.
================================================
FILE: chain.go
================================================
package cron
import (
"fmt"
"runtime"
"sync"
"time"
)
// JobWrapper decorates the given Job with some behavior.
type JobWrapper func(Job) Job
// Chain is a sequence of JobWrappers that decorates submitted jobs with
// cross-cutting behaviors like logging or synchronization.
type Chain struct {
wrappers []JobWrapper
}
// NewChain returns a Chain consisting of the given JobWrappers.
func NewChain(c ...JobWrapper) Chain {
return Chain{c}
}
// Then decorates the given job with all JobWrappers in the chain.
//
// This:
// NewChain(m1, m2, m3).Then(job)
// is equivalent to:
// m1(m2(m3(job)))
func (c Chain) Then(j Job) Job {
for i := range c.wrappers {
j = c.wrappers[len(c.wrappers)-i-1](j)
}
return j
}
// Recover panics in wrapped jobs and log them with the provided logger.
func Recover(logger Logger) JobWrapper {
return func(j Job) Job {
return FuncJob(func() {
defer func() {
if r := recover(); r != nil {
const size = 64 << 10
buf := make([]byte, size)
buf = buf[:runtime.Stack(buf, false)]
err, ok := r.(error)
if !ok {
err = fmt.Errorf("%v", r)
}
logger.Error(err, "panic", "stack", "...\n"+string(buf))
}
}()
j.Run()
})
}
}
// DelayIfStillRunning serializes jobs, delaying subsequent runs until the
// previous one is complete. Jobs running after a delay of more than a minute
// have the delay logged at Info.
func DelayIfStillRunning(logger Logger) JobWrapper {
return func(j Job) Job {
var mu sync.Mutex
return FuncJob(func() {
start := time.Now()
mu.Lock()
defer mu.Unlock()
if dur := time.Since(start); dur > time.Minute {
logger.Info("delay", "duration", dur)
}
j.Run()
})
}
}
// SkipIfStillRunning skips an invocation of the Job if a previous invocation is
// still running. It logs skips to the given logger at Info level.
func SkipIfStillRunning(logger Logger) JobWrapper {
return func(j Job) Job {
var ch = make(chan struct{}, 1)
ch <- struct{}{}
return FuncJob(func() {
select {
case v := <-ch:
defer func() { ch <- v }()
j.Run()
default:
logger.Info("skip")
}
})
}
}
================================================
FILE: chain_test.go
================================================
package cron
import (
"io/ioutil"
"log"
"reflect"
"sync"
"testing"
"time"
)
func appendingJob(slice *[]int, value int) Job {
var m sync.Mutex
return FuncJob(func() {
m.Lock()
*slice = append(*slice, value)
m.Unlock()
})
}
func appendingWrapper(slice *[]int, value int) JobWrapper {
return func(j Job) Job {
return FuncJob(func() {
appendingJob(slice, value).Run()
j.Run()
})
}
}
func TestChain(t *testing.T) {
var nums []int
var (
append1 = appendingWrapper(&nums, 1)
append2 = appendingWrapper(&nums, 2)
append3 = appendingWrapper(&nums, 3)
append4 = appendingJob(&nums, 4)
)
NewChain(append1, append2, append3).Then(append4).Run()
if !reflect.DeepEqual(nums, []int{1, 2, 3, 4}) {
t.Error("unexpected order of calls:", nums)
}
}
func TestChainRecover(t *testing.T) {
panickingJob := FuncJob(func() {
panic("panickingJob panics")
})
t.Run("panic exits job by default", func(t *testing.T) {
defer func() {
if err := recover(); err == nil {
t.Errorf("panic expected, but none received")
}
}()
NewChain().Then(panickingJob).
Run()
})
t.Run("Recovering JobWrapper recovers", func(t *testing.T) {
NewChain(Recover(PrintfLogger(log.New(ioutil.Discard, "", 0)))).
Then(panickingJob).
Run()
})
t.Run("composed with the *IfStillRunning wrappers", func(t *testing.T) {
NewChain(Recover(PrintfLogger(log.New(ioutil.Discard, "", 0)))).
Then(panickingJob).
Run()
})
}
type countJob struct {
m sync.Mutex
started int
done int
delay time.Duration
}
func (j *countJob) Run() {
j.m.Lock()
j.started++
j.m.Unlock()
time.Sleep(j.delay)
j.m.Lock()
j.done++
j.m.Unlock()
}
func (j *countJob) Started() int {
defer j.m.Unlock()
j.m.Lock()
return j.started
}
func (j *countJob) Done() int {
defer j.m.Unlock()
j.m.Lock()
return j.done
}
func TestChainDelayIfStillRunning(t *testing.T) {
t.Run("runs immediately", func(t *testing.T) {
var j countJob
wrappedJob := NewChain(DelayIfStillRunning(DiscardLogger)).Then(&j)
go wrappedJob.Run()
time.Sleep(2 * time.Millisecond) // Give the job 2ms to complete.
if c := j.Done(); c != 1 {
t.Errorf("expected job run once, immediately, got %d", c)
}
})
t.Run("second run immediate if first done", func(t *testing.T) {
var j countJob
wrappedJob := NewChain(DelayIfStillRunning(DiscardLogger)).Then(&j)
go func() {
go wrappedJob.Run()
time.Sleep(time.Millisecond)
go wrappedJob.Run()
}()
time.Sleep(3 * time.Millisecond) // Give both jobs 3ms to complete.
if c := j.Done(); c != 2 {
t.Errorf("expected job run twice, immediately, got %d", c)
}
})
t.Run("second run delayed if first not done", func(t *testing.T) {
var j countJob
j.delay = 10 * time.Millisecond
wrappedJob := NewChain(DelayIfStillRunning(DiscardLogger)).Then(&j)
go func() {
go wrappedJob.Run()
time.Sleep(time.Millisecond)
go wrappedJob.Run()
}()
// After 5ms, the first job is still in progress, and the second job was
// run but should be waiting for it to finish.
time.Sleep(5 * time.Millisecond)
started, done := j.Started(), j.Done()
if started != 1 || done != 0 {
t.Error("expected first job started, but not finished, got", started, done)
}
// Verify that the second job completes.
time.Sleep(25 * time.Millisecond)
started, done = j.Started(), j.Done()
if started != 2 || done != 2 {
t.Error("expected both jobs done, got", started, done)
}
})
}
func TestChainSkipIfStillRunning(t *testing.T) {
t.Run("runs immediately", func(t *testing.T) {
var j countJob
wrappedJob := NewChain(SkipIfStillRunning(DiscardLogger)).Then(&j)
go wrappedJob.Run()
time.Sleep(2 * time.Millisecond) // Give the job 2ms to complete.
if c := j.Done(); c != 1 {
t.Errorf("expected job run once, immediately, got %d", c)
}
})
t.Run("second run immediate if first done", func(t *testing.T) {
var j countJob
wrappedJob := NewChain(SkipIfStillRunning(DiscardLogger)).Then(&j)
go func() {
go wrappedJob.Run()
time.Sleep(time.Millisecond)
go wrappedJob.Run()
}()
time.Sleep(3 * time.Millisecond) // Give both jobs 3ms to complete.
if c := j.Done(); c != 2 {
t.Errorf("expected job run twice, immediately, got %d", c)
}
})
t.Run("second run skipped if first not done", func(t *testing.T) {
var j countJob
j.delay = 10 * time.Millisecond
wrappedJob := NewChain(SkipIfStillRunning(DiscardLogger)).Then(&j)
go func() {
go wrappedJob.Run()
time.Sleep(time.Millisecond)
go wrappedJob.Run()
}()
// After 5ms, the first job is still in progress, and the second job was
// aleady skipped.
time.Sleep(5 * time.Millisecond)
started, done := j.Started(), j.Done()
if started != 1 || done != 0 {
t.Error("expected first job started, but not finished, got", started, done)
}
// Verify that the first job completes and second does not run.
time.Sleep(25 * time.Millisecond)
started, done = j.Started(), j.Done()
if started != 1 || done != 1 {
t.Error("expected second job skipped, got", started, done)
}
})
t.Run("skip 10 jobs on rapid fire", func(t *testing.T) {
var j countJob
j.delay = 10 * time.Millisecond
wrappedJob := NewChain(SkipIfStillRunning(DiscardLogger)).Then(&j)
for i := 0; i < 11; i++ {
go wrappedJob.Run()
}
time.Sleep(200 * time.Millisecond)
done := j.Done()
if done != 1 {
t.Error("expected 1 jobs executed, 10 jobs dropped, got", done)
}
})
t.Run("different jobs independent", func(t *testing.T) {
var j1, j2 countJob
j1.delay = 10 * time.Millisecond
j2.delay = 10 * time.Millisecond
chain := NewChain(SkipIfStillRunning(DiscardLogger))
wrappedJob1 := chain.Then(&j1)
wrappedJob2 := chain.Then(&j2)
for i := 0; i < 11; i++ {
go wrappedJob1.Run()
go wrappedJob2.Run()
}
time.Sleep(100 * time.Millisecond)
var (
done1 = j1.Done()
done2 = j2.Done()
)
if done1 != 1 || done2 != 1 {
t.Error("expected both jobs executed once, got", done1, "and", done2)
}
})
}
================================================
FILE: constantdelay.go
================================================
package cron
import "time"
// ConstantDelaySchedule represents a simple recurring duty cycle, e.g. "Every 5 minutes".
// It does not support jobs more frequent than once a second.
type ConstantDelaySchedule struct {
Delay time.Duration
}
// Every returns a crontab Schedule that activates once every duration.
// Delays of less than a second are not supported (will round up to 1 second).
// Any fields less than a Second are truncated.
func Every(duration time.Duration) ConstantDelaySchedule {
if duration < time.Second {
duration = time.Second
}
return ConstantDelaySchedule{
Delay: duration - time.Duration(duration.Nanoseconds())%time.Second,
}
}
// Next returns the next time this should be run.
// This rounds so that the next activation time will be on the second.
func (schedule ConstantDelaySchedule) Next(t time.Time) time.Time {
return t.Add(schedule.Delay - time.Duration(t.Nanosecond())*time.Nanosecond)
}
================================================
FILE: constantdelay_test.go
================================================
package cron
import (
"testing"
"time"
)
func TestConstantDelayNext(t *testing.T) {
tests := []struct {
time string
delay time.Duration
expected string
}{
// Simple cases
{"Mon Jul 9 14:45 2012", 15*time.Minute + 50*time.Nanosecond, "Mon Jul 9 15:00 2012"},
{"Mon Jul 9 14:59 2012", 15 * time.Minute, "Mon Jul 9 15:14 2012"},
{"Mon Jul 9 14:59:59 2012", 15 * time.Minute, "Mon Jul 9 15:14:59 2012"},
// Wrap around hours
{"Mon Jul 9 15:45 2012", 35 * time.Minute, "Mon Jul 9 16:20 2012"},
// Wrap around days
{"Mon Jul 9 23:46 2012", 14 * time.Minute, "Tue Jul 10 00:00 2012"},
{"Mon Jul 9 23:45 2012", 35 * time.Minute, "Tue Jul 10 00:20 2012"},
{"Mon Jul 9 23:35:51 2012", 44*time.Minute + 24*time.Second, "Tue Jul 10 00:20:15 2012"},
{"Mon Jul 9 23:35:51 2012", 25*time.Hour + 44*time.Minute + 24*time.Second, "Thu Jul 11 01:20:15 2012"},
// Wrap around months
{"Mon Jul 9 23:35 2012", 91*24*time.Hour + 25*time.Minute, "Thu Oct 9 00:00 2012"},
// Wrap around minute, hour, day, month, and year
{"Mon Dec 31 23:59:45 2012", 15 * time.Second, "Tue Jan 1 00:00:00 2013"},
// Round to nearest second on the delay
{"Mon Jul 9 14:45 2012", 15*time.Minute + 50*time.Nanosecond, "Mon Jul 9 15:00 2012"},
// Round up to 1 second if the duration is less.
{"Mon Jul 9 14:45:00 2012", 15 * time.Millisecond, "Mon Jul 9 14:45:01 2012"},
// Round to nearest second when calculating the next time.
{"Mon Jul 9 14:45:00.005 2012", 15 * time.Minute, "Mon Jul 9 15:00 2012"},
// Round to nearest second for both.
{"Mon Jul 9 14:45:00.005 2012", 15*time.Minute + 50*time.Nanosecond, "Mon Jul 9 15:00 2012"},
}
for _, c := range tests {
actual := Every(c.delay).Next(getTime(c.time))
expected := getTime(c.expected)
if actual != expected {
t.Errorf("%s, \"%s\": (expected) %v != %v (actual)", c.time, c.delay, expected, actual)
}
}
}
================================================
FILE: cron.go
================================================
package cron
import (
"context"
"sort"
"sync"
"time"
)
// Cron keeps track of any number of entries, invoking the associated func as
// specified by the schedule. It may be started, stopped, and the entries may
// be inspected while running.
type Cron struct {
entries []*Entry
chain Chain
stop chan struct{}
add chan *Entry
remove chan EntryID
snapshot chan chan []Entry
running bool
logger Logger
runningMu sync.Mutex
location *time.Location
parser ScheduleParser
nextID EntryID
jobWaiter sync.WaitGroup
}
// ScheduleParser is an interface for schedule spec parsers that return a Schedule
type ScheduleParser interface {
Parse(spec string) (Schedule, error)
}
// Job is an interface for submitted cron jobs.
type Job interface {
Run()
}
// Schedule describes a job's duty cycle.
type Schedule interface {
// Next returns the next activation time, later than the given time.
// Next is invoked initially, and then each time the job is run.
Next(time.Time) time.Time
}
// EntryID identifies an entry within a Cron instance
type EntryID int
// Entry consists of a schedule and the func to execute on that schedule.
type Entry struct {
// ID is the cron-assigned ID of this entry, which may be used to look up a
// snapshot or remove it.
ID EntryID
// Schedule on which this job should be run.
Schedule Schedule
// Next time the job will run, or the zero time if Cron has not been
// started or this entry's schedule is unsatisfiable
Next time.Time
// Prev is the last time this job was run, or the zero time if never.
Prev time.Time
// WrappedJob is the thing to run when the Schedule is activated.
WrappedJob Job
// Job is the thing that was submitted to cron.
// It is kept around so that user code that needs to get at the job later,
// e.g. via Entries() can do so.
Job Job
}
// Valid returns true if this is not the zero entry.
func (e Entry) Valid() bool { return e.ID != 0 }
// byTime is a wrapper for sorting the entry array by time
// (with zero time at the end).
type byTime []*Entry
func (s byTime) Len() int { return len(s) }
func (s byTime) Swap(i, j int) { s[i], s[j] = s[j], s[i] }
func (s byTime) Less(i, j int) bool {
// Two zero times should return false.
// Otherwise, zero is "greater" than any other time.
// (To sort it at the end of the list.)
if s[i].Next.IsZero() {
return false
}
if s[j].Next.IsZero() {
return true
}
return s[i].Next.Before(s[j].Next)
}
// New returns a new Cron job runner, modified by the given options.
//
// Available Settings
//
// Time Zone
// Description: The time zone in which schedules are interpreted
// Default: time.Local
//
// Parser
// Description: Parser converts cron spec strings into cron.Schedules.
// Default: Accepts this spec: https://en.wikipedia.org/wiki/Cron
//
// Chain
// Description: Wrap submitted jobs to customize behavior.
// Default: A chain that recovers panics and logs them to stderr.
//
// See "cron.With*" to modify the default behavior.
func New(opts ...Option) *Cron {
c := &Cron{
entries: nil,
chain: NewChain(),
add: make(chan *Entry),
stop: make(chan struct{}),
snapshot: make(chan chan []Entry),
remove: make(chan EntryID),
running: false,
runningMu: sync.Mutex{},
logger: DefaultLogger,
location: time.Local,
parser: standardParser,
}
for _, opt := range opts {
opt(c)
}
return c
}
// FuncJob is a wrapper that turns a func() into a cron.Job
type FuncJob func()
func (f FuncJob) Run() { f() }
// AddFunc adds a func to the Cron to be run on the given schedule.
// The spec is parsed using the time zone of this Cron instance as the default.
// An opaque ID is returned that can be used to later remove it.
func (c *Cron) AddFunc(spec string, cmd func()) (EntryID, error) {
return c.AddJob(spec, FuncJob(cmd))
}
// AddJob adds a Job to the Cron to be run on the given schedule.
// The spec is parsed using the time zone of this Cron instance as the default.
// An opaque ID is returned that can be used to later remove it.
func (c *Cron) AddJob(spec string, cmd Job) (EntryID, error) {
schedule, err := c.parser.Parse(spec)
if err != nil {
return 0, err
}
return c.Schedule(schedule, cmd), nil
}
// Schedule adds a Job to the Cron to be run on the given schedule.
// The job is wrapped with the configured Chain.
func (c *Cron) Schedule(schedule Schedule, cmd Job) EntryID {
c.runningMu.Lock()
defer c.runningMu.Unlock()
c.nextID++
entry := &Entry{
ID: c.nextID,
Schedule: schedule,
WrappedJob: c.chain.Then(cmd),
Job: cmd,
}
if !c.running {
c.entries = append(c.entries, entry)
} else {
c.add <- entry
}
return entry.ID
}
// Entries returns a snapshot of the cron entries.
func (c *Cron) Entries() []Entry {
c.runningMu.Lock()
defer c.runningMu.Unlock()
if c.running {
replyChan := make(chan []Entry, 1)
c.snapshot <- replyChan
return <-replyChan
}
return c.entrySnapshot()
}
// Location gets the time zone location
func (c *Cron) Location() *time.Location {
return c.location
}
// Entry returns a snapshot of the given entry, or nil if it couldn't be found.
func (c *Cron) Entry(id EntryID) Entry {
for _, entry := range c.Entries() {
if id == entry.ID {
return entry
}
}
return Entry{}
}
// Remove an entry from being run in the future.
func (c *Cron) Remove(id EntryID) {
c.runningMu.Lock()
defer c.runningMu.Unlock()
if c.running {
c.remove <- id
} else {
c.removeEntry(id)
}
}
// Start the cron scheduler in its own goroutine, or no-op if already started.
func (c *Cron) Start() {
c.runningMu.Lock()
defer c.runningMu.Unlock()
if c.running {
return
}
c.running = true
go c.run()
}
// Run the cron scheduler, or no-op if already running.
func (c *Cron) Run() {
c.runningMu.Lock()
if c.running {
c.runningMu.Unlock()
return
}
c.running = true
c.runningMu.Unlock()
c.run()
}
// run the scheduler.. this is private just due to the need to synchronize
// access to the 'running' state variable.
func (c *Cron) run() {
c.logger.Info("start")
// Figure out the next activation times for each entry.
now := c.now()
for _, entry := range c.entries {
entry.Next = entry.Schedule.Next(now)
c.logger.Info("schedule", "now", now, "entry", entry.ID, "next", entry.Next)
}
for {
// Determine the next entry to run.
sort.Sort(byTime(c.entries))
var timer *time.Timer
if len(c.entries) == 0 || c.entries[0].Next.IsZero() {
// If there are no entries yet, just sleep - it still handles new entries
// and stop requests.
timer = time.NewTimer(100000 * time.Hour)
} else {
timer = time.NewTimer(c.entries[0].Next.Sub(now))
}
for {
select {
case now = <-timer.C:
now = now.In(c.location)
c.logger.Info("wake", "now", now)
// Run every entry whose next time was less than now
for _, e := range c.entries {
if e.Next.After(now) || e.Next.IsZero() {
break
}
c.startJob(e.WrappedJob)
e.Prev = e.Next
e.Next = e.Schedule.Next(now)
c.logger.Info("run", "now", now, "entry", e.ID, "next", e.Next)
}
case newEntry := <-c.add:
timer.Stop()
now = c.now()
newEntry.Next = newEntry.Schedule.Next(now)
c.entries = append(c.entries, newEntry)
c.logger.Info("added", "now", now, "entry", newEntry.ID, "next", newEntry.Next)
case replyChan := <-c.snapshot:
replyChan <- c.entrySnapshot()
continue
case <-c.stop:
timer.Stop()
c.logger.Info("stop")
return
case id := <-c.remove:
timer.Stop()
now = c.now()
c.removeEntry(id)
c.logger.Info("removed", "entry", id)
}
break
}
}
}
// startJob runs the given job in a new goroutine.
func (c *Cron) startJob(j Job) {
c.jobWaiter.Add(1)
go func() {
defer c.jobWaiter.Done()
j.Run()
}()
}
// now returns current time in c location
func (c *Cron) now() time.Time {
return time.Now().In(c.location)
}
// Stop stops the cron scheduler if it is running; otherwise it does nothing.
// A context is returned so the caller can wait for running jobs to complete.
func (c *Cron) Stop() context.Context {
c.runningMu.Lock()
defer c.runningMu.Unlock()
if c.running {
c.stop <- struct{}{}
c.running = false
}
ctx, cancel := context.WithCancel(context.Background())
go func() {
c.jobWaiter.Wait()
cancel()
}()
return ctx
}
// entrySnapshot returns a copy of the current cron entry list.
func (c *Cron) entrySnapshot() []Entry {
var entries = make([]Entry, len(c.entries))
for i, e := range c.entries {
entries[i] = *e
}
return entries
}
func (c *Cron) removeEntry(id EntryID) {
var entries []*Entry
for _, e := range c.entries {
if e.ID != id {
entries = append(entries, e)
}
}
c.entries = entries
}
================================================
FILE: cron_test.go
================================================
package cron
import (
"bytes"
"fmt"
"log"
"strings"
"sync"
"sync/atomic"
"testing"
"time"
)
// Many tests schedule a job for every second, and then wait at most a second
// for it to run. This amount is just slightly larger than 1 second to
// compensate for a few milliseconds of runtime.
const OneSecond = 1*time.Second + 50*time.Millisecond
type syncWriter struct {
wr bytes.Buffer
m sync.Mutex
}
func (sw *syncWriter) Write(data []byte) (n int, err error) {
sw.m.Lock()
n, err = sw.wr.Write(data)
sw.m.Unlock()
return
}
func (sw *syncWriter) String() string {
sw.m.Lock()
defer sw.m.Unlock()
return sw.wr.String()
}
func newBufLogger(sw *syncWriter) Logger {
return PrintfLogger(log.New(sw, "", log.LstdFlags))
}
func TestFuncPanicRecovery(t *testing.T) {
var buf syncWriter
cron := New(WithParser(secondParser),
WithChain(Recover(newBufLogger(&buf))))
cron.Start()
defer cron.Stop()
cron.AddFunc("* * * * * ?", func() {
panic("YOLO")
})
select {
case <-time.After(OneSecond):
if !strings.Contains(buf.String(), "YOLO") {
t.Error("expected a panic to be logged, got none")
}
return
}
}
type DummyJob struct{}
func (d DummyJob) Run() {
panic("YOLO")
}
func TestJobPanicRecovery(t *testing.T) {
var job DummyJob
var buf syncWriter
cron := New(WithParser(secondParser),
WithChain(Recover(newBufLogger(&buf))))
cron.Start()
defer cron.Stop()
cron.AddJob("* * * * * ?", job)
select {
case <-time.After(OneSecond):
if !strings.Contains(buf.String(), "YOLO") {
t.Error("expected a panic to be logged, got none")
}
return
}
}
// Start and stop cron with no entries.
func TestNoEntries(t *testing.T) {
cron := newWithSeconds()
cron.Start()
select {
case <-time.After(OneSecond):
t.Fatal("expected cron will be stopped immediately")
case <-stop(cron):
}
}
// Start, stop, then add an entry. Verify entry doesn't run.
func TestStopCausesJobsToNotRun(t *testing.T) {
wg := &sync.WaitGroup{}
wg.Add(1)
cron := newWithSeconds()
cron.Start()
cron.Stop()
cron.AddFunc("* * * * * ?", func() { wg.Done() })
select {
case <-time.After(OneSecond):
// No job ran!
case <-wait(wg):
t.Fatal("expected stopped cron does not run any job")
}
}
// Add a job, start cron, expect it runs.
func TestAddBeforeRunning(t *testing.T) {
wg := &sync.WaitGroup{}
wg.Add(1)
cron := newWithSeconds()
cron.AddFunc("* * * * * ?", func() { wg.Done() })
cron.Start()
defer cron.Stop()
// Give cron 2 seconds to run our job (which is always activated).
select {
case <-time.After(OneSecond):
t.Fatal("expected job runs")
case <-wait(wg):
}
}
// Start cron, add a job, expect it runs.
func TestAddWhileRunning(t *testing.T) {
wg := &sync.WaitGroup{}
wg.Add(1)
cron := newWithSeconds()
cron.Start()
defer cron.Stop()
cron.AddFunc("* * * * * ?", func() { wg.Done() })
select {
case <-time.After(OneSecond):
t.Fatal("expected job runs")
case <-wait(wg):
}
}
// Test for #34. Adding a job after calling start results in multiple job invocations
func TestAddWhileRunningWithDelay(t *testing.T) {
cron := newWithSeconds()
cron.Start()
defer cron.Stop()
time.Sleep(5 * time.Second)
var calls int64
cron.AddFunc("* * * * * *", func() { atomic.AddInt64(&calls, 1) })
<-time.After(OneSecond)
if atomic.LoadInt64(&calls) != 1 {
t.Errorf("called %d times, expected 1\n", calls)
}
}
// Add a job, remove a job, start cron, expect nothing runs.
func TestRemoveBeforeRunning(t *testing.T) {
wg := &sync.WaitGroup{}
wg.Add(1)
cron := newWithSeconds()
id, _ := cron.AddFunc("* * * * * ?", func() { wg.Done() })
cron.Remove(id)
cron.Start()
defer cron.Stop()
select {
case <-time.After(OneSecond):
// Success, shouldn't run
case <-wait(wg):
t.FailNow()
}
}
// Start cron, add a job, remove it, expect it doesn't run.
func TestRemoveWhileRunning(t *testing.T) {
wg := &sync.WaitGroup{}
wg.Add(1)
cron := newWithSeconds()
cron.Start()
defer cron.Stop()
id, _ := cron.AddFunc("* * * * * ?", func() { wg.Done() })
cron.Remove(id)
select {
case <-time.After(OneSecond):
case <-wait(wg):
t.FailNow()
}
}
// Test timing with Entries.
func TestSnapshotEntries(t *testing.T) {
wg := &sync.WaitGroup{}
wg.Add(1)
cron := New()
cron.AddFunc("@every 2s", func() { wg.Done() })
cron.Start()
defer cron.Stop()
// Cron should fire in 2 seconds. After 1 second, call Entries.
select {
case <-time.After(OneSecond):
cron.Entries()
}
// Even though Entries was called, the cron should fire at the 2 second mark.
select {
case <-time.After(OneSecond):
t.Error("expected job runs at 2 second mark")
case <-wait(wg):
}
}
// Test that the entries are correctly sorted.
// Add a bunch of long-in-the-future entries, and an immediate entry, and ensure
// that the immediate entry runs immediately.
// Also: Test that multiple jobs run in the same instant.
func TestMultipleEntries(t *testing.T) {
wg := &sync.WaitGroup{}
wg.Add(2)
cron := newWithSeconds()
cron.AddFunc("0 0 0 1 1 ?", func() {})
cron.AddFunc("* * * * * ?", func() { wg.Done() })
id1, _ := cron.AddFunc("* * * * * ?", func() { t.Fatal() })
id2, _ := cron.AddFunc("* * * * * ?", func() { t.Fatal() })
cron.AddFunc("0 0 0 31 12 ?", func() {})
cron.AddFunc("* * * * * ?", func() { wg.Done() })
cron.Remove(id1)
cron.Start()
cron.Remove(id2)
defer cron.Stop()
select {
case <-time.After(OneSecond):
t.Error("expected job run in proper order")
case <-wait(wg):
}
}
// Test running the same job twice.
func TestRunningJobTwice(t *testing.T) {
wg := &sync.WaitGroup{}
wg.Add(2)
cron := newWithSeconds()
cron.AddFunc("0 0 0 1 1 ?", func() {})
cron.AddFunc("0 0 0 31 12 ?", func() {})
cron.AddFunc("* * * * * ?", func() { wg.Done() })
cron.Start()
defer cron.Stop()
select {
case <-time.After(2 * OneSecond):
t.Error("expected job fires 2 times")
case <-wait(wg):
}
}
func TestRunningMultipleSchedules(t *testing.T) {
wg := &sync.WaitGroup{}
wg.Add(2)
cron := newWithSeconds()
cron.AddFunc("0 0 0 1 1 ?", func() {})
cron.AddFunc("0 0 0 31 12 ?", func() {})
cron.AddFunc("* * * * * ?", func() { wg.Done() })
cron.Schedule(Every(time.Minute), FuncJob(func() {}))
cron.Schedule(Every(time.Second), FuncJob(func() { wg.Done() }))
cron.Schedule(Every(time.Hour), FuncJob(func() {}))
cron.Start()
defer cron.Stop()
select {
case <-time.After(2 * OneSecond):
t.Error("expected job fires 2 times")
case <-wait(wg):
}
}
// Test that the cron is run in the local time zone (as opposed to UTC).
func TestLocalTimezone(t *testing.T) {
wg := &sync.WaitGroup{}
wg.Add(2)
now := time.Now()
// FIX: Issue #205
// This calculation doesn't work in seconds 58 or 59.
// Take the easy way out and sleep.
if now.Second() >= 58 {
time.Sleep(2 * time.Second)
now = time.Now()
}
spec := fmt.Sprintf("%d,%d %d %d %d %d ?",
now.Second()+1, now.Second()+2, now.Minute(), now.Hour(), now.Day(), now.Month())
cron := newWithSeconds()
cron.AddFunc(spec, func() { wg.Done() })
cron.Start()
defer cron.Stop()
select {
case <-time.After(OneSecond * 2):
t.Error("expected job fires 2 times")
case <-wait(wg):
}
}
// Test that the cron is run in the given time zone (as opposed to local).
func TestNonLocalTimezone(t *testing.T) {
wg := &sync.WaitGroup{}
wg.Add(2)
loc, err := time.LoadLocation("Atlantic/Cape_Verde")
if err != nil {
fmt.Printf("Failed to load time zone Atlantic/Cape_Verde: %+v", err)
t.Fail()
}
now := time.Now().In(loc)
// FIX: Issue #205
// This calculation doesn't work in seconds 58 or 59.
// Take the easy way out and sleep.
if now.Second() >= 58 {
time.Sleep(2 * time.Second)
now = time.Now().In(loc)
}
spec := fmt.Sprintf("%d,%d %d %d %d %d ?",
now.Second()+1, now.Second()+2, now.Minute(), now.Hour(), now.Day(), now.Month())
cron := New(WithLocation(loc), WithParser(secondParser))
cron.AddFunc(spec, func() { wg.Done() })
cron.Start()
defer cron.Stop()
select {
case <-time.After(OneSecond * 2):
t.Error("expected job fires 2 times")
case <-wait(wg):
}
}
// Test that calling stop before start silently returns without
// blocking the stop channel.
func TestStopWithoutStart(t *testing.T) {
cron := New()
cron.Stop()
}
type testJob struct {
wg *sync.WaitGroup
name string
}
func (t testJob) Run() {
t.wg.Done()
}
// Test that adding an invalid job spec returns an error
func TestInvalidJobSpec(t *testing.T) {
cron := New()
_, err := cron.AddJob("this will not parse", nil)
if err == nil {
t.Errorf("expected an error with invalid spec, got nil")
}
}
// Test blocking run method behaves as Start()
func TestBlockingRun(t *testing.T) {
wg := &sync.WaitGroup{}
wg.Add(1)
cron := newWithSeconds()
cron.AddFunc("* * * * * ?", func() { wg.Done() })
var unblockChan = make(chan struct{})
go func() {
cron.Run()
close(unblockChan)
}()
defer cron.Stop()
select {
case <-time.After(OneSecond):
t.Error("expected job fires")
case <-unblockChan:
t.Error("expected that Run() blocks")
case <-wait(wg):
}
}
// Test that double-running is a no-op
func TestStartNoop(t *testing.T) {
var tickChan = make(chan struct{}, 2)
cron := newWithSeconds()
cron.AddFunc("* * * * * ?", func() {
tickChan <- struct{}{}
})
cron.Start()
defer cron.Stop()
// Wait for the first firing to ensure the runner is going
<-tickChan
cron.Start()
<-tickChan
// Fail if this job fires again in a short period, indicating a double-run
select {
case <-time.After(time.Millisecond):
case <-tickChan:
t.Error("expected job fires exactly twice")
}
}
// Simple test using Runnables.
func TestJob(t *testing.T) {
wg := &sync.WaitGroup{}
wg.Add(1)
cron := newWithSeconds()
cron.AddJob("0 0 0 30 Feb ?", testJob{wg, "job0"})
cron.AddJob("0 0 0 1 1 ?", testJob{wg, "job1"})
job2, _ := cron.AddJob("* * * * * ?", testJob{wg, "job2"})
cron.AddJob("1 0 0 1 1 ?", testJob{wg, "job3"})
cron.Schedule(Every(5*time.Second+5*time.Nanosecond), testJob{wg, "job4"})
job5 := cron.Schedule(Every(5*time.Minute), testJob{wg, "job5"})
// Test getting an Entry pre-Start.
if actualName := cron.Entry(job2).Job.(testJob).name; actualName != "job2" {
t.Error("wrong job retrieved:", actualName)
}
if actualName := cron.Entry(job5).Job.(testJob).name; actualName != "job5" {
t.Error("wrong job retrieved:", actualName)
}
cron.Start()
defer cron.Stop()
select {
case <-time.After(OneSecond):
t.FailNow()
case <-wait(wg):
}
// Ensure the entries are in the right order.
expecteds := []string{"job2", "job4", "job5", "job1", "job3", "job0"}
var actuals []string
for _, entry := range cron.Entries() {
actuals = append(actuals, entry.Job.(testJob).name)
}
for i, expected := range expecteds {
if actuals[i] != expected {
t.Fatalf("Jobs not in the right order. (expected) %s != %s (actual)", expecteds, actuals)
}
}
// Test getting Entries.
if actualName := cron.Entry(job2).Job.(testJob).name; actualName != "job2" {
t.Error("wrong job retrieved:", actualName)
}
if actualName := cron.Entry(job5).Job.(testJob).name; actualName != "job5" {
t.Error("wrong job retrieved:", actualName)
}
}
// Issue #206
// Ensure that the next run of a job after removing an entry is accurate.
func TestScheduleAfterRemoval(t *testing.T) {
var wg1 sync.WaitGroup
var wg2 sync.WaitGroup
wg1.Add(1)
wg2.Add(1)
// The first time this job is run, set a timer and remove the other job
// 750ms later. Correct behavior would be to still run the job again in
// 250ms, but the bug would cause it to run instead 1s later.
var calls int
var mu sync.Mutex
cron := newWithSeconds()
hourJob := cron.Schedule(Every(time.Hour), FuncJob(func() {}))
cron.Schedule(Every(time.Second), FuncJob(func() {
mu.Lock()
defer mu.Unlock()
switch calls {
case 0:
wg1.Done()
calls++
case 1:
time.Sleep(750 * time.Millisecond)
cron.Remove(hourJob)
calls++
case 2:
calls++
wg2.Done()
case 3:
panic("unexpected 3rd call")
}
}))
cron.Start()
defer cron.Stop()
// the first run might be any length of time 0 - 1s, since the schedule
// rounds to the second. wait for the first run to true up.
wg1.Wait()
select {
case <-time.After(2 * OneSecond):
t.Error("expected job fires 2 times")
case <-wait(&wg2):
}
}
type ZeroSchedule struct{}
func (*ZeroSchedule) Next(time.Time) time.Time {
return time.Time{}
}
// Tests that job without time does not run
func TestJobWithZeroTimeDoesNotRun(t *testing.T) {
cron := newWithSeconds()
var calls int64
cron.AddFunc("* * * * * *", func() { atomic.AddInt64(&calls, 1) })
cron.Schedule(new(ZeroSchedule), FuncJob(func() { t.Error("expected zero task will not run") }))
cron.Start()
defer cron.Stop()
<-time.After(OneSecond)
if atomic.LoadInt64(&calls) != 1 {
t.Errorf("called %d times, expected 1\n", calls)
}
}
func TestStopAndWait(t *testing.T) {
t.Run("nothing running, returns immediately", func(t *testing.T) {
cron := newWithSeconds()
cron.Start()
ctx := cron.Stop()
select {
case <-ctx.Done():
case <-time.After(time.Millisecond):
t.Error("context was not done immediately")
}
})
t.Run("repeated calls to Stop", func(t *testing.T) {
cron := newWithSeconds()
cron.Start()
_ = cron.Stop()
time.Sleep(time.Millisecond)
ctx := cron.Stop()
select {
case <-ctx.Done():
case <-time.After(time.Millisecond):
t.Error("context was not done immediately")
}
})
t.Run("a couple fast jobs added, still returns immediately", func(t *testing.T) {
cron := newWithSeconds()
cron.AddFunc("* * * * * *", func() {})
cron.Start()
cron.AddFunc("* * * * * *", func() {})
cron.AddFunc("* * * * * *", func() {})
cron.AddFunc("* * * * * *", func() {})
time.Sleep(time.Second)
ctx := cron.Stop()
select {
case <-ctx.Done():
case <-time.After(time.Millisecond):
t.Error("context was not done immediately")
}
})
t.Run("a couple fast jobs and a slow job added, waits for slow job", func(t *testing.T) {
cron := newWithSeconds()
cron.AddFunc("* * * * * *", func() {})
cron.Start()
cron.AddFunc("* * * * * *", func() { time.Sleep(2 * time.Second) })
cron.AddFunc("* * * * * *", func() {})
time.Sleep(time.Second)
ctx := cron.Stop()
// Verify that it is not done for at least 750ms
select {
case <-ctx.Done():
t.Error("context was done too quickly immediately")
case <-time.After(750 * time.Millisecond):
// expected, because the job sleeping for 1 second is still running
}
// Verify that it IS done in the next 500ms (giving 250ms buffer)
select {
case <-ctx.Done():
// expected
case <-time.After(1500 * time.Millisecond):
t.Error("context not done after job should have completed")
}
})
t.Run("repeated calls to stop, waiting for completion and after", func(t *testing.T) {
cron := newWithSeconds()
cron.AddFunc("* * * * * *", func() {})
cron.AddFunc("* * * * * *", func() { time.Sleep(2 * time.Second) })
cron.Start()
cron.AddFunc("* * * * * *", func() {})
time.Sleep(time.Second)
ctx := cron.Stop()
ctx2 := cron.Stop()
// Verify that it is not done for at least 1500ms
select {
case <-ctx.Done():
t.Error("context was done too quickly immediately")
case <-ctx2.Done():
t.Error("context2 was done too quickly immediately")
case <-time.After(1500 * time.Millisecond):
// expected, because the job sleeping for 2 seconds is still running
}
// Verify that it IS done in the next 1s (giving 500ms buffer)
select {
case <-ctx.Done():
// expected
case <-time.After(time.Second):
t.Error("context not done after job should have completed")
}
// Verify that ctx2 is also done.
select {
case <-ctx2.Done():
// expected
case <-time.After(time.Millisecond):
t.Error("context2 not done even though context1 is")
}
// Verify that a new context retrieved from stop is immediately done.
ctx3 := cron.Stop()
select {
case <-ctx3.Done():
// expected
case <-time.After(time.Millisecond):
t.Error("context not done even when cron Stop is completed")
}
})
}
func TestMultiThreadedStartAndStop(t *testing.T) {
cron := New()
go cron.Run()
time.Sleep(2 * time.Millisecond)
cron.Stop()
}
func wait(wg *sync.WaitGroup) chan bool {
ch := make(chan bool)
go func() {
wg.Wait()
ch <- true
}()
return ch
}
func stop(cron *Cron) chan bool {
ch := make(chan bool)
go func() {
cron.Stop()
ch <- true
}()
return ch
}
// newWithSeconds returns a Cron with the seconds field enabled.
func newWithSeconds() *Cron {
return New(WithParser(secondParser), WithChain())
}
================================================
FILE: doc.go
================================================
/*
Package cron implements a cron spec parser and job runner.
Installation
To download the specific tagged release, run:
go get github.com/robfig/cron/v3@v3.0.0
Import it in your program as:
import "github.com/robfig/cron/v3"
It requires Go 1.11 or later due to usage of Go Modules.
Usage
Callers may register Funcs to be invoked on a given schedule. Cron will run
them in their own goroutines.
c := cron.New()
c.AddFunc("30 * * * *", func() { fmt.Println("Every hour on the half hour") })
c.AddFunc("30 3-6,20-23 * * *", func() { fmt.Println(".. in the range 3-6am, 8-11pm") })
c.AddFunc("CRON_TZ=Asia/Tokyo 30 04 * * *", func() { fmt.Println("Runs at 04:30 Tokyo time every day") })
c.AddFunc("@hourly", func() { fmt.Println("Every hour, starting an hour from now") })
c.AddFunc("@every 1h30m", func() { fmt.Println("Every hour thirty, starting an hour thirty from now") })
c.Start()
..
// Funcs are invoked in their own goroutine, asynchronously.
...
// Funcs may also be added to a running Cron
c.AddFunc("@daily", func() { fmt.Println("Every day") })
..
// Inspect the cron job entries' next and previous run times.
inspect(c.Entries())
..
c.Stop() // Stop the scheduler (does not stop any jobs already running).
CRON Expression Format
A cron expression represents a set of times, using 5 space-separated fields.
Field name | Mandatory? | Allowed values | Allowed special characters
---------- | ---------- | -------------- | --------------------------
Minutes | Yes | 0-59 | * / , -
Hours | Yes | 0-23 | * / , -
Day of month | Yes | 1-31 | * / , - ?
Month | Yes | 1-12 or JAN-DEC | * / , -
Day of week | Yes | 0-6 or SUN-SAT | * / , - ?
Month and Day-of-week field values are case insensitive. "SUN", "Sun", and
"sun" are equally accepted.
The specific interpretation of the format is based on the Cron Wikipedia page:
https://en.wikipedia.org/wiki/Cron
Alternative Formats
Alternative Cron expression formats support other fields like seconds. You can
implement that by creating a custom Parser as follows.
cron.New(
cron.WithParser(
cron.NewParser(
cron.SecondOptional | cron.Minute | cron.Hour | cron.Dom | cron.Month | cron.Dow | cron.Descriptor)))
Since adding Seconds is the most common modification to the standard cron spec,
cron provides a builtin function to do that, which is equivalent to the custom
parser you saw earlier, except that its seconds field is REQUIRED:
cron.New(cron.WithSeconds())
That emulates Quartz, the most popular alternative Cron schedule format:
http://www.quartz-scheduler.org/documentation/quartz-2.x/tutorials/crontrigger.html
Special Characters
Asterisk ( * )
The asterisk indicates that the cron expression will match for all values of the
field; e.g., using an asterisk in the 5th field (month) would indicate every
month.
Slash ( / )
Slashes are used to describe increments of ranges. For example 3-59/15 in the
1st field (minutes) would indicate the 3rd minute of the hour and every 15
minutes thereafter. The form "*\/..." is equivalent to the form "first-last/...",
that is, an increment over the largest possible range of the field. The form
"N/..." is accepted as meaning "N-MAX/...", that is, starting at N, use the
increment until the end of that specific range. It does not wrap around.
Comma ( , )
Commas are used to separate items of a list. For example, using "MON,WED,FRI" in
the 5th field (day of week) would mean Mondays, Wednesdays and Fridays.
Hyphen ( - )
Hyphens are used to define ranges. For example, 9-17 would indicate every
hour between 9am and 5pm inclusive.
Question mark ( ? )
Question mark may be used instead of '*' for leaving either day-of-month or
day-of-week blank.
Predefined schedules
You may use one of several pre-defined schedules in place of a cron expression.
Entry | Description | Equivalent To
----- | ----------- | -------------
@yearly (or @annually) | Run once a year, midnight, Jan. 1st | 0 0 1 1 *
@monthly | Run once a month, midnight, first of month | 0 0 1 * *
@weekly | Run once a week, midnight between Sat/Sun | 0 0 * * 0
@daily (or @midnight) | Run once a day, midnight | 0 0 * * *
@hourly | Run once an hour, beginning of hour | 0 * * * *
Intervals
You may also schedule a job to execute at fixed intervals, starting at the time it's added
or cron is run. This is supported by formatting the cron spec like this:
@every <duration>
where "duration" is a string accepted by time.ParseDuration
(http://golang.org/pkg/time/#ParseDuration).
For example, "@every 1h30m10s" would indicate a schedule that activates after
1 hour, 30 minutes, 10 seconds, and then every interval after that.
Note: The interval does not take the job runtime into account. For example,
if a job takes 3 minutes to run, and it is scheduled to run every 5 minutes,
it will have only 2 minutes of idle time between each run.
Time zones
By default, all interpretation and scheduling is done in the machine's local
time zone (time.Local). You can specify a different time zone on construction:
cron.New(
cron.WithLocation(time.UTC))
Individual cron schedules may also override the time zone they are to be
interpreted in by providing an additional space-separated field at the beginning
of the cron spec, of the form "CRON_TZ=Asia/Tokyo".
For example:
# Runs at 6am in time.Local
cron.New().AddFunc("0 6 * * ?", ...)
# Runs at 6am in America/New_York
nyc, _ := time.LoadLocation("America/New_York")
c := cron.New(cron.WithLocation(nyc))
c.AddFunc("0 6 * * ?", ...)
# Runs at 6am in Asia/Tokyo
cron.New().AddFunc("CRON_TZ=Asia/Tokyo 0 6 * * ?", ...)
# Runs at 6am in Asia/Tokyo
c := cron.New(cron.WithLocation(nyc))
c.SetLocation("America/New_York")
c.AddFunc("CRON_TZ=Asia/Tokyo 0 6 * * ?", ...)
The prefix "TZ=(TIME ZONE)" is also supported for legacy compatibility.
Be aware that jobs scheduled during daylight-savings leap-ahead transitions will
not be run!
Job Wrappers
A Cron runner may be configured with a chain of job wrappers to add
cross-cutting functionality to all submitted jobs. For example, they may be used
to achieve the following effects:
- Recover any panics from jobs (activated by default)
- Delay a job's execution if the previous run hasn't completed yet
- Skip a job's execution if the previous run hasn't completed yet
- Log each job's invocations
Install wrappers for all jobs added to a cron using the `cron.WithChain` option:
cron.New(cron.WithChain(
cron.SkipIfStillRunning(logger),
))
Install wrappers for individual jobs by explicitly wrapping them:
job = cron.NewChain(
cron.SkipIfStillRunning(logger),
).Then(job)
Thread safety
Since the Cron service runs concurrently with the calling code, some amount of
care must be taken to ensure proper synchronization.
All cron methods are designed to be correctly synchronized as long as the caller
ensures that invocations have a clear happens-before ordering between them.
Logging
Cron defines a Logger interface that is a subset of the one defined in
github.com/go-logr/logr. It has two logging levels (Info and Error), and
parameters are key/value pairs. This makes it possible for cron logging to plug
into structured logging systems. An adapter, [Verbose]PrintfLogger, is provided
to wrap the standard library *log.Logger.
For additional insight into Cron operations, verbose logging may be activated
which will record job runs, scheduling decisions, and added or removed jobs.
Activate it with a one-off logger as follows:
cron.New(
cron.WithLogger(
cron.VerbosePrintfLogger(log.New(os.Stdout, "cron: ", log.LstdFlags))))
Implementation
Cron entries are stored in an array, sorted by their next activation time. Cron
sleeps until the next job is due to be run.
Upon waking:
- it runs each entry that is active on that second
- it calculates the next run times for the jobs that were run
- it re-sorts the array of entries by next activation time.
- it goes to sleep until the soonest job.
*/
package cron
================================================
FILE: go.mod
================================================
module github.com/robfig/cron/v3
go 1.12
================================================
FILE: logger.go
================================================
package cron
import (
"io/ioutil"
"log"
"os"
"strings"
"time"
)
// DefaultLogger is used by Cron if none is specified.
var DefaultLogger Logger = PrintfLogger(log.New(os.Stdout, "cron: ", log.LstdFlags))
// DiscardLogger can be used by callers to discard all log messages.
var DiscardLogger Logger = PrintfLogger(log.New(ioutil.Discard, "", 0))
// Logger is the interface used in this package for logging, so that any backend
// can be plugged in. It is a subset of the github.com/go-logr/logr interface.
type Logger interface {
// Info logs routine messages about cron's operation.
Info(msg string, keysAndValues ...interface{})
// Error logs an error condition.
Error(err error, msg string, keysAndValues ...interface{})
}
// PrintfLogger wraps a Printf-based logger (such as the standard library "log")
// into an implementation of the Logger interface which logs errors only.
func PrintfLogger(l interface{ Printf(string, ...interface{}) }) Logger {
return printfLogger{l, false}
}
// VerbosePrintfLogger wraps a Printf-based logger (such as the standard library
// "log") into an implementation of the Logger interface which logs everything.
func VerbosePrintfLogger(l interface{ Printf(string, ...interface{}) }) Logger {
return printfLogger{l, true}
}
type printfLogger struct {
logger interface{ Printf(string, ...interface{}) }
logInfo bool
}
func (pl printfLogger) Info(msg string, keysAndValues ...interface{}) {
if pl.logInfo {
keysAndValues = formatTimes(keysAndValues)
pl.logger.Printf(
formatString(len(keysAndValues)),
append([]interface{}{msg}, keysAndValues...)...)
}
}
func (pl printfLogger) Error(err error, msg string, keysAndValues ...interface{}) {
keysAndValues = formatTimes(keysAndValues)
pl.logger.Printf(
formatString(len(keysAndValues)+2),
append([]interface{}{msg, "error", err}, keysAndValues...)...)
}
// formatString returns a logfmt-like format string for the number of
// key/values.
func formatString(numKeysAndValues int) string {
var sb strings.Builder
sb.WriteString("%s")
if numKeysAndValues > 0 {
sb.WriteString(", ")
}
for i := 0; i < numKeysAndValues/2; i++ {
if i > 0 {
sb.WriteString(", ")
}
sb.WriteString("%v=%v")
}
return sb.String()
}
// formatTimes formats any time.Time values as RFC3339.
func formatTimes(keysAndValues []interface{}) []interface{} {
var formattedArgs []interface{}
for _, arg := range keysAndValues {
if t, ok := arg.(time.Time); ok {
arg = t.Format(time.RFC3339)
}
formattedArgs = append(formattedArgs, arg)
}
return formattedArgs
}
================================================
FILE: option.go
================================================
package cron
import (
"time"
)
// Option represents a modification to the default behavior of a Cron.
type Option func(*Cron)
// WithLocation overrides the timezone of the cron instance.
func WithLocation(loc *time.Location) Option {
return func(c *Cron) {
c.location = loc
}
}
// WithSeconds overrides the parser used for interpreting job schedules to
// include a seconds field as the first one.
func WithSeconds() Option {
return WithParser(NewParser(
Second | Minute | Hour | Dom | Month | Dow | Descriptor,
))
}
// WithParser overrides the parser used for interpreting job schedules.
func WithParser(p ScheduleParser) Option {
return func(c *Cron) {
c.parser = p
}
}
// WithChain specifies Job wrappers to apply to all jobs added to this cron.
// Refer to the Chain* functions in this package for provided wrappers.
func WithChain(wrappers ...JobWrapper) Option {
return func(c *Cron) {
c.chain = NewChain(wrappers...)
}
}
// WithLogger uses the provided logger.
func WithLogger(logger Logger) Option {
return func(c *Cron) {
c.logger = logger
}
}
================================================
FILE: option_test.go
================================================
package cron
import (
"log"
"strings"
"testing"
"time"
)
func TestWithLocation(t *testing.T) {
c := New(WithLocation(time.UTC))
if c.location != time.UTC {
t.Errorf("expected UTC, got %v", c.location)
}
}
func TestWithParser(t *testing.T) {
var parser = NewParser(Dow)
c := New(WithParser(parser))
if c.parser != parser {
t.Error("expected provided parser")
}
}
func TestWithVerboseLogger(t *testing.T) {
var buf syncWriter
var logger = log.New(&buf, "", log.LstdFlags)
c := New(WithLogger(VerbosePrintfLogger(logger)))
if c.logger.(printfLogger).logger != logger {
t.Error("expected provided logger")
}
c.AddFunc("@every 1s", func() {})
c.Start()
time.Sleep(OneSecond)
c.Stop()
out := buf.String()
if !strings.Contains(out, "schedule,") ||
!strings.Contains(out, "run,") {
t.Error("expected to see some actions, got:", out)
}
}
================================================
FILE: parser.go
================================================
package cron
import (
"fmt"
"math"
"strconv"
"strings"
"time"
)
// Configuration options for creating a parser. Most options specify which
// fields should be included, while others enable features. If a field is not
// included the parser will assume a default value. These options do not change
// the order fields are parse in.
type ParseOption int
const (
Second ParseOption = 1 << iota // Seconds field, default 0
SecondOptional // Optional seconds field, default 0
Minute // Minutes field, default 0
Hour // Hours field, default 0
Dom // Day of month field, default *
Month // Month field, default *
Dow // Day of week field, default *
DowOptional // Optional day of week field, default *
Descriptor // Allow descriptors such as @monthly, @weekly, etc.
)
var places = []ParseOption{
Second,
Minute,
Hour,
Dom,
Month,
Dow,
}
var defaults = []string{
"0",
"0",
"0",
"*",
"*",
"*",
}
// A custom Parser that can be configured.
type Parser struct {
options ParseOption
}
// NewParser creates a Parser with custom options.
//
// It panics if more than one Optional is given, since it would be impossible to
// correctly infer which optional is provided or missing in general.
//
// Examples
//
// // Standard parser without descriptors
// specParser := NewParser(Minute | Hour | Dom | Month | Dow)
// sched, err := specParser.Parse("0 0 15 */3 *")
//
// // Same as above, just excludes time fields
// specParser := NewParser(Dom | Month | Dow)
// sched, err := specParser.Parse("15 */3 *")
//
// // Same as above, just makes Dow optional
// specParser := NewParser(Dom | Month | DowOptional)
// sched, err := specParser.Parse("15 */3")
//
func NewParser(options ParseOption) Parser {
optionals := 0
if options&DowOptional > 0 {
optionals++
}
if options&SecondOptional > 0 {
optionals++
}
if optionals > 1 {
panic("multiple optionals may not be configured")
}
return Parser{options}
}
// Parse returns a new crontab schedule representing the given spec.
// It returns a descriptive error if the spec is not valid.
// It accepts crontab specs and features configured by NewParser.
func (p Parser) Parse(spec string) (Schedule, error) {
if len(spec) == 0 {
return nil, fmt.Errorf("empty spec string")
}
// Extract timezone if present
var loc = time.Local
if strings.HasPrefix(spec, "TZ=") || strings.HasPrefix(spec, "CRON_TZ=") {
var err error
i := strings.Index(spec, " ")
eq := strings.Index(spec, "=")
if loc, err = time.LoadLocation(spec[eq+1 : i]); err != nil {
return nil, fmt.Errorf("provided bad location %s: %v", spec[eq+1:i], err)
}
spec = strings.TrimSpace(spec[i:])
}
// Handle named schedules (descriptors), if configured
if strings.HasPrefix(spec, "@") {
if p.options&Descriptor == 0 {
return nil, fmt.Errorf("parser does not accept descriptors: %v", spec)
}
return parseDescriptor(spec, loc)
}
// Split on whitespace.
fields := strings.Fields(spec)
// Validate & fill in any omitted or optional fields
var err error
fields, err = normalizeFields(fields, p.options)
if err != nil {
return nil, err
}
field := func(field string, r bounds) uint64 {
if err != nil {
return 0
}
var bits uint64
bits, err = getField(field, r)
return bits
}
var (
second = field(fields[0], seconds)
minute = field(fields[1], minutes)
hour = field(fields[2], hours)
dayofmonth = field(fields[3], dom)
month = field(fields[4], months)
dayofweek = field(fields[5], dow)
)
if err != nil {
return nil, err
}
return &SpecSchedule{
Second: second,
Minute: minute,
Hour: hour,
Dom: dayofmonth,
Month: month,
Dow: dayofweek,
Location: loc,
}, nil
}
// normalizeFields takes a subset set of the time fields and returns the full set
// with defaults (zeroes) populated for unset fields.
//
// As part of performing this function, it also validates that the provided
// fields are compatible with the configured options.
func normalizeFields(fields []string, options ParseOption) ([]string, error) {
// Validate optionals & add their field to options
optionals := 0
if options&SecondOptional > 0 {
options |= Second
optionals++
}
if options&DowOptional > 0 {
options |= Dow
optionals++
}
if optionals > 1 {
return nil, fmt.Errorf("multiple optionals may not be configured")
}
// Figure out how many fields we need
max := 0
for _, place := range places {
if options&place > 0 {
max++
}
}
min := max - optionals
// Validate number of fields
if count := len(fields); count < min || count > max {
if min == max {
return nil, fmt.Errorf("expected exactly %d fields, found %d: %s", min, count, fields)
}
return nil, fmt.Errorf("expected %d to %d fields, found %d: %s", min, max, count, fields)
}
// Populate the optional field if not provided
if min < max && len(fields) == min {
switch {
case options&DowOptional > 0:
fields = append(fields, defaults[5]) // TODO: improve access to default
case options&SecondOptional > 0:
fields = append([]string{defaults[0]}, fields...)
default:
return nil, fmt.Errorf("unknown optional field")
}
}
// Populate all fields not part of options with their defaults
n := 0
expandedFields := make([]string, len(places))
copy(expandedFields, defaults)
for i, place := range places {
if options&place > 0 {
expandedFields[i] = fields[n]
n++
}
}
return expandedFields, nil
}
var standardParser = NewParser(
Minute | Hour | Dom | Month | Dow | Descriptor,
)
// ParseStandard returns a new crontab schedule representing the given
// standardSpec (https://en.wikipedia.org/wiki/Cron). It requires 5 entries
// representing: minute, hour, day of month, month and day of week, in that
// order. It returns a descriptive error if the spec is not valid.
//
// It accepts
// - Standard crontab specs, e.g. "* * * * ?"
// - Descriptors, e.g. "@midnight", "@every 1h30m"
func ParseStandard(standardSpec string) (Schedule, error) {
return standardParser.Parse(standardSpec)
}
// getField returns an Int with the bits set representing all of the times that
// the field represents or error parsing field value. A "field" is a comma-separated
// list of "ranges".
func getField(field string, r bounds) (uint64, error) {
var bits uint64
ranges := strings.FieldsFunc(field, func(r rune) bool { return r == ',' })
for _, expr := range ranges {
bit, err := getRange(expr, r)
if err != nil {
return bits, err
}
bits |= bit
}
return bits, nil
}
// getRange returns the bits indicated by the given expression:
// number | number "-" number [ "/" number ]
// or error parsing range.
func getRange(expr string, r bounds) (uint64, error) {
var (
start, end, step uint
rangeAndStep = strings.Split(expr, "/")
lowAndHigh = strings.Split(rangeAndStep[0], "-")
singleDigit = len(lowAndHigh) == 1
err error
)
var extra uint64
if lowAndHigh[0] == "*" || lowAndHigh[0] == "?" {
start = r.min
end = r.max
extra = starBit
} else {
start, err = parseIntOrName(lowAndHigh[0], r.names)
if err != nil {
return 0, err
}
switch len(lowAndHigh) {
case 1:
end = start
case 2:
end, err = parseIntOrName(lowAndHigh[1], r.names)
if err != nil {
return 0, err
}
default:
return 0, fmt.Errorf("too many hyphens: %s", expr)
}
}
switch len(rangeAndStep) {
case 1:
step = 1
case 2:
step, err = mustParseInt(rangeAndStep[1])
if err != nil {
return 0, err
}
// Special handling: "N/step" means "N-max/step".
if singleDigit {
end = r.max
}
if step > 1 {
extra = 0
}
default:
return 0, fmt.Errorf("too many slashes: %s", expr)
}
if start < r.min {
return 0, fmt.Errorf("beginning of range (%d) below minimum (%d): %s", start, r.min, expr)
}
if end > r.max {
return 0, fmt.Errorf("end of range (%d) above maximum (%d): %s", end, r.max, expr)
}
if start > end {
return 0, fmt.Errorf("beginning of range (%d) beyond end of range (%d): %s", start, end, expr)
}
if step == 0 {
return 0, fmt.Errorf("step of range should be a positive number: %s", expr)
}
return getBits(start, end, step) | extra, nil
}
// parseIntOrName returns the (possibly-named) integer contained in expr.
func parseIntOrName(expr string, names map[string]uint) (uint, error) {
if names != nil {
if namedInt, ok := names[strings.ToLower(expr)]; ok {
return namedInt, nil
}
}
return mustParseInt(expr)
}
// mustParseInt parses the given expression as an int or returns an error.
func mustParseInt(expr string) (uint, error) {
num, err := strconv.Atoi(expr)
if err != nil {
return 0, fmt.Errorf("failed to parse int from %s: %s", expr, err)
}
if num < 0 {
return 0, fmt.Errorf("negative number (%d) not allowed: %s", num, expr)
}
return uint(num), nil
}
// getBits sets all bits in the range [min, max], modulo the given step size.
func getBits(min, max, step uint) uint64 {
var bits uint64
// If step is 1, use shifts.
if step == 1 {
return ^(math.MaxUint64 << (max + 1)) & (math.MaxUint64 << min)
}
// Else, use a simple loop.
for i := min; i <= max; i += step {
bits |= 1 << i
}
return bits
}
// all returns all bits within the given bounds. (plus the star bit)
func all(r bounds) uint64 {
return getBits(r.min, r.max, 1) | starBit
}
// parseDescriptor returns a predefined schedule for the expression, or error if none matches.
func parseDescriptor(descriptor string, loc *time.Location) (Schedule, error) {
switch descriptor {
case "@yearly", "@annually":
return &SpecSchedule{
Second: 1 << seconds.min,
Minute: 1 << minutes.min,
Hour: 1 << hours.min,
Dom: 1 << dom.min,
Month: 1 << months.min,
Dow: all(dow),
Location: loc,
}, nil
case "@monthly":
return &SpecSchedule{
Second: 1 << seconds.min,
Minute: 1 << minutes.min,
Hour: 1 << hours.min,
Dom: 1 << dom.min,
Month: all(months),
Dow: all(dow),
Location: loc,
}, nil
case "@weekly":
return &SpecSchedule{
Second: 1 << seconds.min,
Minute: 1 << minutes.min,
Hour: 1 << hours.min,
Dom: all(dom),
Month: all(months),
Dow: 1 << dow.min,
Location: loc,
}, nil
case "@daily", "@midnight":
return &SpecSchedule{
Second: 1 << seconds.min,
Minute: 1 << minutes.min,
Hour: 1 << hours.min,
Dom: all(dom),
Month: all(months),
Dow: all(dow),
Location: loc,
}, nil
case "@hourly":
return &SpecSchedule{
Second: 1 << seconds.min,
Minute: 1 << minutes.min,
Hour: all(hours),
Dom: all(dom),
Month: all(months),
Dow: all(dow),
Location: loc,
}, nil
}
const every = "@every "
if strings.HasPrefix(descriptor, every) {
duration, err := time.ParseDuration(descriptor[len(every):])
if err != nil {
return nil, fmt.Errorf("failed to parse duration %s: %s", descriptor, err)
}
return Every(duration), nil
}
return nil, fmt.Errorf("unrecognized descriptor: %s", descriptor)
}
================================================
FILE: parser_test.go
================================================
package cron
import (
"reflect"
"strings"
"testing"
"time"
)
var secondParser = NewParser(Second | Minute | Hour | Dom | Month | DowOptional | Descriptor)
func TestRange(t *testing.T) {
zero := uint64(0)
ranges := []struct {
expr string
min, max uint
expected uint64
err string
}{
{"5", 0, 7, 1 << 5, ""},
{"0", 0, 7, 1 << 0, ""},
{"7", 0, 7, 1 << 7, ""},
{"5-5", 0, 7, 1 << 5, ""},
{"5-6", 0, 7, 1<<5 | 1<<6, ""},
{"5-7", 0, 7, 1<<5 | 1<<6 | 1<<7, ""},
{"5-6/2", 0, 7, 1 << 5, ""},
{"5-7/2", 0, 7, 1<<5 | 1<<7, ""},
{"5-7/1", 0, 7, 1<<5 | 1<<6 | 1<<7, ""},
{"*", 1, 3, 1<<1 | 1<<2 | 1<<3 | starBit, ""},
{"*/2", 1, 3, 1<<1 | 1<<3, ""},
{"5--5", 0, 0, zero, "too many hyphens"},
{"jan-x", 0, 0, zero, "failed to parse int from"},
{"2-x", 1, 5, zero, "failed to parse int from"},
{"*/-12", 0, 0, zero, "negative number"},
{"*//2", 0, 0, zero, "too many slashes"},
{"1", 3, 5, zero, "below minimum"},
{"6", 3, 5, zero, "above maximum"},
{"5-3", 3, 5, zero, "beyond end of range"},
{"*/0", 0, 0, zero, "should be a positive number"},
}
for _, c := range ranges {
actual, err := getRange(c.expr, bounds{c.min, c.max, nil})
if len(c.err) != 0 && (err == nil || !strings.Contains(err.Error(), c.err)) {
t.Errorf("%s => expected %v, got %v", c.expr, c.err, err)
}
if len(c.err) == 0 && err != nil {
t.Errorf("%s => unexpected error %v", c.expr, err)
}
if actual != c.expected {
t.Errorf("%s => expected %d, got %d", c.expr, c.expected, actual)
}
}
}
func TestField(t *testing.T) {
fields := []struct {
expr string
min, max uint
expected uint64
}{
{"5", 1, 7, 1 << 5},
{"5,6", 1, 7, 1<<5 | 1<<6},
{"5,6,7", 1, 7, 1<<5 | 1<<6 | 1<<7},
{"1,5-7/2,3", 1, 7, 1<<1 | 1<<5 | 1<<7 | 1<<3},
}
for _, c := range fields {
actual, _ := getField(c.expr, bounds{c.min, c.max, nil})
if actual != c.expected {
t.Errorf("%s => expected %d, got %d", c.expr, c.expected, actual)
}
}
}
func TestAll(t *testing.T) {
allBits := []struct {
r bounds
expected uint64
}{
{minutes, 0xfffffffffffffff}, // 0-59: 60 ones
{hours, 0xffffff}, // 0-23: 24 ones
{dom, 0xfffffffe}, // 1-31: 31 ones, 1 zero
{months, 0x1ffe}, // 1-12: 12 ones, 1 zero
{dow, 0x7f}, // 0-6: 7 ones
}
for _, c := range allBits {
actual := all(c.r) // all() adds the starBit, so compensate for that..
if c.expected|starBit != actual {
t.Errorf("%d-%d/%d => expected %b, got %b",
c.r.min, c.r.max, 1, c.expected|starBit, actual)
}
}
}
func TestBits(t *testing.T) {
bits := []struct {
min, max, step uint
expected uint64
}{
{0, 0, 1, 0x1},
{1, 1, 1, 0x2},
{1, 5, 2, 0x2a}, // 101010
{1, 4, 2, 0xa}, // 1010
}
for _, c := range bits {
actual := getBits(c.min, c.max, c.step)
if c.expected != actual {
t.Errorf("%d-%d/%d => expected %b, got %b",
c.min, c.max, c.step, c.expected, actual)
}
}
}
func TestParseScheduleErrors(t *testing.T) {
var tests = []struct{ expr, err string }{
{"* 5 j * * *", "failed to parse int from"},
{"@every Xm", "failed to parse duration"},
{"@unrecognized", "unrecognized descriptor"},
{"* * * *", "expected 5 to 6 fields"},
{"", "empty spec string"},
}
for _, c := range tests {
actual, err := secondParser.Parse(c.expr)
if err == nil || !strings.Contains(err.Error(), c.err) {
t.Errorf("%s => expected %v, got %v", c.expr, c.err, err)
}
if actual != nil {
t.Errorf("expected nil schedule on error, got %v", actual)
}
}
}
func TestParseSchedule(t *testing.T) {
tokyo, _ := time.LoadLocation("Asia/Tokyo")
entries := []struct {
parser Parser
expr string
expected Schedule
}{
{secondParser, "0 5 * * * *", every5min(time.Local)},
{standardParser, "5 * * * *", every5min(time.Local)},
{secondParser, "CRON_TZ=UTC 0 5 * * * *", every5min(time.UTC)},
{standardParser, "CRON_TZ=UTC 5 * * * *", every5min(time.UTC)},
{secondParser, "CRON_TZ=Asia/Tokyo 0 5 * * * *", every5min(tokyo)},
{secondParser, "@every 5m", ConstantDelaySchedule{5 * time.Minute}},
{secondParser, "@midnight", midnight(time.Local)},
{secondParser, "TZ=UTC @midnight", midnight(time.UTC)},
{secondParser, "TZ=Asia/Tokyo @midnight", midnight(tokyo)},
{secondParser, "@yearly", annual(time.Local)},
{secondParser, "@annually", annual(time.Local)},
{
parser: secondParser,
expr: "* 5 * * * *",
expected: &SpecSchedule{
Second: all(seconds),
Minute: 1 << 5,
Hour: all(hours),
Dom: all(dom),
Month: all(months),
Dow: all(dow),
Location: time.Local,
},
},
}
for _, c := range entries {
actual, err := c.parser.Parse(c.expr)
if err != nil {
t.Errorf("%s => unexpected error %v", c.expr, err)
}
if !reflect.DeepEqual(actual, c.expected) {
t.Errorf("%s => expected %b, got %b", c.expr, c.expected, actual)
}
}
}
func TestOptionalSecondSchedule(t *testing.T) {
parser := NewParser(SecondOptional | Minute | Hour | Dom | Month | Dow | Descriptor)
entries := []struct {
expr string
expected Schedule
}{
{"0 5 * * * *", every5min(time.Local)},
{"5 5 * * * *", every5min5s(time.Local)},
{"5 * * * *", every5min(time.Local)},
}
for _, c := range entries {
actual, err := parser.Parse(c.expr)
if err != nil {
t.Errorf("%s => unexpected error %v", c.expr, err)
}
if !reflect.DeepEqual(actual, c.expected) {
t.Errorf("%s => expected %b, got %b", c.expr, c.expected, actual)
}
}
}
func TestNormalizeFields(t *testing.T) {
tests := []struct {
name string
input []string
options ParseOption
expected []string
}{
{
"AllFields_NoOptional",
[]string{"0", "5", "*", "*", "*", "*"},
Second | Minute | Hour | Dom | Month | Dow | Descriptor,
[]string{"0", "5", "*", "*", "*", "*"},
},
{
"AllFields_SecondOptional_Provided",
[]string{"0", "5", "*", "*", "*", "*"},
SecondOptional | Minute | Hour | Dom | Month | Dow | Descriptor,
[]string{"0", "5", "*", "*", "*", "*"},
},
{
"AllFields_SecondOptional_NotProvided",
[]string{"5", "*", "*", "*", "*"},
SecondOptional | Minute | Hour | Dom | Month | Dow | Descriptor,
[]string{"0", "5", "*", "*", "*", "*"},
},
{
"SubsetFields_NoOptional",
[]string{"5", "15", "*"},
Hour | Dom | Month,
[]string{"0", "0", "5", "15", "*", "*"},
},
{
"SubsetFields_DowOptional_Provided",
[]string{"5", "15", "*", "4"},
Hour | Dom | Month | DowOptional,
[]string{"0", "0", "5", "15", "*", "4"},
},
{
"SubsetFields_DowOptional_NotProvided",
[]string{"5", "15", "*"},
Hour | Dom | Month | DowOptional,
[]string{"0", "0", "5", "15", "*", "*"},
},
{
"SubsetFields_SecondOptional_NotProvided",
[]string{"5", "15", "*"},
SecondOptional | Hour | Dom | Month,
[]string{"0", "0", "5", "15", "*", "*"},
},
}
for _, test := range tests {
t.Run(test.name, func(t *testing.T) {
actual, err := normalizeFields(test.input, test.options)
if err != nil {
t.Errorf("unexpected error: %v", err)
}
if !reflect.DeepEqual(actual, test.expected) {
t.Errorf("expected %v, got %v", test.expected, actual)
}
})
}
}
func TestNormalizeFields_Errors(t *testing.T) {
tests := []struct {
name string
input []string
options ParseOption
err string
}{
{
"TwoOptionals",
[]string{"0", "5", "*", "*", "*", "*"},
SecondOptional | Minute | Hour | Dom | Month | DowOptional,
"",
},
{
"TooManyFields",
[]string{"0", "5", "*", "*"},
SecondOptional | Minute | Hour,
"",
},
{
"NoFields",
[]string{},
SecondOptional | Minute | Hour,
"",
},
{
"TooFewFields",
[]string{"*"},
SecondOptional | Minute | Hour,
"",
},
}
for _, test := range tests {
t.Run(test.name, func(t *testing.T) {
actual, err := normalizeFields(test.input, test.options)
if err == nil {
t.Errorf("expected an error, got none. results: %v", actual)
}
if !strings.Contains(err.Error(), test.err) {
t.Errorf("expected error %q, got %q", test.err, err.Error())
}
})
}
}
func TestStandardSpecSchedule(t *testing.T) {
entries := []struct {
expr string
expected Schedule
err string
}{
{
expr: "5 * * * *",
expected: &SpecSchedule{1 << seconds.min, 1 << 5, all(hours), all(dom), all(months), all(dow), time.Local},
},
{
expr: "@every 5m",
expected: ConstantDelaySchedule{time.Duration(5) * time.Minute},
},
{
expr: "5 j * * *",
err: "failed to parse int from",
},
{
expr: "* * * *",
err: "expected exactly 5 fields",
},
}
for _, c := range entries {
actual, err := ParseStandard(c.expr)
if len(c.err) != 0 && (err == nil || !strings.Contains(err.Error(), c.err)) {
t.Errorf("%s => expected %v, got %v", c.expr, c.err, err)
}
if len(c.err) == 0 && err != nil {
t.Errorf("%s => unexpected error %v", c.expr, err)
}
if !reflect.DeepEqual(actual, c.expected) {
t.Errorf("%s => expected %b, got %b", c.expr, c.expected, actual)
}
}
}
func TestNoDescriptorParser(t *testing.T) {
parser := NewParser(Minute | Hour)
_, err := parser.Parse("@every 1m")
if err == nil {
t.Error("expected an error, got none")
}
}
func every5min(loc *time.Location) *SpecSchedule {
return &SpecSchedule{1 << 0, 1 << 5, all(hours), all(dom), all(months), all(dow), loc}
}
func every5min5s(loc *time.Location) *SpecSchedule {
return &SpecSchedule{1 << 5, 1 << 5, all(hours), all(dom), all(months), all(dow), loc}
}
func midnight(loc *time.Location) *SpecSchedule {
return &SpecSchedule{1, 1, 1, all(dom), all(months), all(dow), loc}
}
func annual(loc *time.Location) *SpecSchedule {
return &SpecSchedule{
Second: 1 << seconds.min,
Minute: 1 << minutes.min,
Hour: 1 << hours.min,
Dom: 1 << dom.min,
Month: 1 << months.min,
Dow: all(dow),
Location: loc,
}
}
================================================
FILE: spec.go
================================================
package cron
import "time"
// SpecSchedule specifies a duty cycle (to the second granularity), based on a
// traditional crontab specification. It is computed initially and stored as bit sets.
type SpecSchedule struct {
Second, Minute, Hour, Dom, Month, Dow uint64
// Override location for this schedule.
Location *time.Location
}
// bounds provides a range of acceptable values (plus a map of name to value).
type bounds struct {
min, max uint
names map[string]uint
}
// The bounds for each field.
var (
seconds = bounds{0, 59, nil}
minutes = bounds{0, 59, nil}
hours = bounds{0, 23, nil}
dom = bounds{1, 31, nil}
months = bounds{1, 12, map[string]uint{
"jan": 1,
"feb": 2,
"mar": 3,
"apr": 4,
"may": 5,
"jun": 6,
"jul": 7,
"aug": 8,
"sep": 9,
"oct": 10,
"nov": 11,
"dec": 12,
}}
dow = bounds{0, 6, map[string]uint{
"sun": 0,
"mon": 1,
"tue": 2,
"wed": 3,
"thu": 4,
"fri": 5,
"sat": 6,
}}
)
const (
// Set the top bit if a star was included in the expression.
starBit = 1 << 63
)
// Next returns the next time this schedule is activated, greater than the given
// time. If no time can be found to satisfy the schedule, return the zero time.
func (s *SpecSchedule) Next(t time.Time) time.Time {
// General approach
//
// For Month, Day, Hour, Minute, Second:
// Check if the time value matches. If yes, continue to the next field.
// If the field doesn't match the schedule, then increment the field until it matches.
// While incrementing the field, a wrap-around brings it back to the beginning
// of the field list (since it is necessary to re-verify previous field
// values)
// Convert the given time into the schedule's timezone, if one is specified.
// Save the original timezone so we can convert back after we find a time.
// Note that schedules without a time zone specified (time.Local) are treated
// as local to the time provided.
origLocation := t.Location()
loc := s.Location
if loc == time.Local {
loc = t.Location()
}
if s.Location != time.Local {
t = t.In(s.Location)
}
// Start at the earliest possible time (the upcoming second).
t = t.Add(1*time.Second - time.Duration(t.Nanosecond())*time.Nanosecond)
// This flag indicates whether a field has been incremented.
added := false
// If no time is found within five years, return zero.
yearLimit := t.Year() + 5
WRAP:
if t.Year() > yearLimit {
return time.Time{}
}
// Find the first applicable month.
// If it's this month, then do nothing.
for 1<<uint(t.Month())&s.Month == 0 {
// If we have to add a month, reset the other parts to 0.
if !added {
added = true
// Otherwise, set the date at the beginning (since the current time is irrelevant).
t = time.Date(t.Year(), t.Month(), 1, 0, 0, 0, 0, loc)
}
t = t.AddDate(0, 1, 0)
// Wrapped around.
if t.Month() == time.January {
goto WRAP
}
}
// Now get a day in that month.
//
// NOTE: This causes issues for daylight savings regimes where midnight does
// not exist. For example: Sao Paulo has DST that transforms midnight on
// 11/3 into 1am. Handle that by noticing when the Hour ends up != 0.
for !dayMatches(s, t) {
if !added {
added = true
t = time.Date(t.Year(), t.Month(), t.Day(), 0, 0, 0, 0, loc)
}
t = t.AddDate(0, 0, 1)
// Notice if the hour is no longer midnight due to DST.
// Add an hour if it's 23, subtract an hour if it's 1.
if t.Hour() != 0 {
if t.Hour() > 12 {
t = t.Add(time.Duration(24-t.Hour()) * time.Hour)
} else {
t = t.Add(time.Duration(-t.Hour()) * time.Hour)
}
}
if t.Day() == 1 {
goto WRAP
}
}
for 1<<uint(t.Hour())&s.Hour == 0 {
if !added {
added = true
t = time.Date(t.Year(), t.Month(), t.Day(), t.Hour(), 0, 0, 0, loc)
}
t = t.Add(1 * time.Hour)
if t.Hour() == 0 {
goto WRAP
}
}
for 1<<uint(t.Minute())&s.Minute == 0 {
if !added {
added = true
t = t.Truncate(time.Minute)
}
t = t.Add(1 * time.Minute)
if t.Minute() == 0 {
goto WRAP
}
}
for 1<<uint(t.Second())&s.Second == 0 {
if !added {
added = true
t = t.Truncate(time.Second)
}
t = t.Add(1 * time.Second)
if t.Second() == 0 {
goto WRAP
}
}
return t.In(origLocation)
}
// dayMatches returns true if the schedule's day-of-week and day-of-month
// restrictions are satisfied by the given time.
func dayMatches(s *SpecSchedule, t time.Time) bool {
var (
domMatch bool = 1<<uint(t.Day())&s.Dom > 0
dowMatch bool = 1<<uint(t.Weekday())&s.Dow > 0
)
if s.Dom&starBit > 0 || s.Dow&starBit > 0 {
return domMatch && dowMatch
}
return domMatch || dowMatch
}
================================================
FILE: spec_test.go
================================================
package cron
import (
"strings"
"testing"
"time"
)
func TestActivation(t *testing.T) {
tests := []struct {
time, spec string
expected bool
}{
// Every fifteen minutes.
{"Mon Jul 9 15:00 2012", "0/15 * * * *", true},
{"Mon Jul 9 15:45 2012", "0/15 * * * *", true},
{"Mon Jul 9 15:40 2012", "0/15 * * * *", false},
// Every fifteen minutes, starting at 5 minutes.
{"Mon Jul 9 15:05 2012", "5/15 * * * *", true},
{"Mon Jul 9 15:20 2012", "5/15 * * * *", true},
{"Mon Jul 9 15:50 2012", "5/15 * * * *", true},
// Named months
{"Sun Jul 15 15:00 2012", "0/15 * * Jul *", true},
{"Sun Jul 15 15:00 2012", "0/15 * * Jun *", false},
// Everything set.
{"Sun Jul 15 08:30 2012", "30 08 ? Jul Sun", true},
{"Sun Jul 15 08:30 2012", "30 08 15 Jul ?", true},
{"Mon Jul 16 08:30 2012", "30 08 ? Jul Sun", false},
{"Mon Jul 16 08:30 2012", "30 08 15 Jul ?", false},
// Predefined schedules
{"Mon Jul 9 15:00 2012", "@hourly", true},
{"Mon Jul 9 15:04 2012", "@hourly", false},
{"Mon Jul 9 15:00 2012", "@daily", false},
{"Mon Jul 9 00:00 2012", "@daily", true},
{"Mon Jul 9 00:00 2012", "@weekly", false},
{"Sun Jul 8 00:00 2012", "@weekly", true},
{"Sun Jul 8 01:00 2012", "@weekly", false},
{"Sun Jul 8 00:00 2012", "@monthly", false},
{"Sun Jul 1 00:00 2012", "@monthly", true},
// Test interaction of DOW and DOM.
// If both are restricted, then only one needs to match.
{"Sun Jul 15 00:00 2012", "* * 1,15 * Sun", true},
{"Fri Jun 15 00:00 2012", "* * 1,15 * Sun", true},
{"Wed Aug 1 00:00 2012", "* * 1,15 * Sun", true},
{"Sun Jul 15 00:00 2012", "* * */10 * Sun", true}, // verifies #70
// However, if one has a star, then both need to match.
{"Sun Jul 15 00:00 2012", "* * * * Mon", false},
{"Mon Jul 9 00:00 2012", "* * 1,15 * *", false},
{"Sun Jul 15 00:00 2012", "* * 1,15 * *", true},
{"Sun Jul 15 00:00 2012", "* * */2 * Sun", true},
}
for _, test := range tests {
sched, err := ParseStandard(test.spec)
if err != nil {
t.Error(err)
continue
}
actual := sched.Next(getTime(test.time).Add(-1 * time.Second))
expected := getTime(test.time)
if test.expected && expected != actual || !test.expected && expected == actual {
t.Errorf("Fail evaluating %s on %s: (expected) %s != %s (actual)",
test.spec, test.time, expected, actual)
}
}
}
func TestNext(t *testing.T) {
runs := []struct {
time, spec string
expected string
}{
// Simple cases
{"Mon Jul 9 14:45 2012", "0 0/15 * * * *", "Mon Jul 9 15:00 2012"},
{"Mon Jul 9 14:59 2012", "0 0/15 * * * *", "Mon Jul 9 15:00 2012"},
{"Mon Jul 9 14:59:59 2012", "0 0/15 * * * *", "Mon Jul 9 15:00 2012"},
// Wrap around hours
{"Mon Jul 9 15:45 2012", "0 20-35/15 * * * *", "Mon Jul 9 16:20 2012"},
// Wrap around days
{"Mon Jul 9 23:46 2012", "0 */15 * * * *", "Tue Jul 10 00:00 2012"},
{"Mon Jul 9 23:45 2012", "0 20-35/15 * * * *", "Tue Jul 10 00:20 2012"},
{"Mon Jul 9 23:35:51 2012", "15/35 20-35/15 * * * *", "Tue Jul 10 00:20:15 2012"},
{"Mon Jul 9 23:35:51 2012", "15/35 20-35/15 1/2 * * *", "Tue Jul 10 01:20:15 2012"},
{"Mon Jul 9 23:35:51 2012", "15/35 20-35/15 10-12 * * *", "Tue Jul 10 10:20:15 2012"},
{"Mon Jul 9 23:35:51 2012", "15/35 20-35/15 1/2 */2 * *", "Thu Jul 11 01:20:15 2012"},
{"Mon Jul 9 23:35:51 2012", "15/35 20-35/15 * 9-20 * *", "Wed Jul 10 00:20:15 2012"},
{"Mon Jul 9 23:35:51 2012", "15/35 20-35/15 * 9-20 Jul *", "Wed Jul 10 00:20:15 2012"},
// Wrap around months
{"Mon Jul 9 23:35 2012", "0 0 0 9 Apr-Oct ?", "Thu Aug 9 00:00 2012"},
{"Mon Jul 9 23:35 2012", "0 0 0 */5 Apr,Aug,Oct Mon", "Tue Aug 1 00:00 2012"},
{"Mon Jul 9 23:35 2012", "0 0 0 */5 Oct Mon", "Mon Oct 1 00:00 2012"},
// Wrap around years
{"Mon Jul 9 23:35 2012", "0 0 0 * Feb Mon", "Mon Feb 4 00:00 2013"},
{"Mon Jul 9 23:35 2012", "0 0 0 * Feb Mon/2", "Fri Feb 1 00:00 2013"},
// Wrap around minute, hour, day, month, and year
{"Mon Dec 31 23:59:45 2012", "0 * * * * *", "Tue Jan 1 00:00:00 2013"},
// Leap year
{"Mon Jul 9 23:35 2012", "0 0 0 29 Feb ?", "Mon Feb 29 00:00 2016"},
// Daylight savings time 2am EST (-5) -> 3am EDT (-4)
{"2012-03-11T00:00:00-0500", "TZ=America/New_York 0 30 2 11 Mar ?", "2013-03-11T02:30:00-0400"},
// hourly job
{"2012-03-11T00:00:00-0500", "TZ=America/New_York 0 0 * * * ?", "2012-03-11T01:00:00-0500"},
{"2012-03-11T01:00:00-0500", "TZ=America/New_York 0 0 * * * ?", "2012-03-11T03:00:00-0400"},
{"2012-03-11T03:00:00-0400", "TZ=America/New_York 0 0 * * * ?", "2012-03-11T04:00:00-0400"},
{"2012-03-11T04:00:00-0400", "TZ=America/New_York 0 0 * * * ?", "2012-03-11T05:00:00-0400"},
// hourly job using CRON_TZ
{"2012-03-11T00:00:00-0500", "CRON_TZ=America/New_York 0 0 * * * ?", "2012-03-11T01:00:00-0500"},
{"2012-03-11T01:00:00-0500", "CRON_TZ=America/New_York 0 0 * * * ?", "2012-03-11T03:00:00-0400"},
{"2012-03-11T03:00:00-0400", "CRON_TZ=America/New_York 0 0 * * * ?", "2012-03-11T04:00:00-0400"},
{"2012-03-11T04:00:00-0400", "CRON_TZ=America/New_York 0 0 * * * ?", "2012-03-11T05:00:00-0400"},
// 1am nightly job
{"2012-03-11T00:00:00-0500", "TZ=America/New_York 0 0 1 * * ?", "2012-03-11T01:00:00-0500"},
{"2012-03-11T01:00:00-0500", "TZ=America/New_York 0 0 1 * * ?", "2012-03-12T01:00:00-0400"},
// 2am nightly job (skipped)
{"2012-03-11T00:00:00-0500", "TZ=America/New_York 0 0 2 * * ?", "2012-03-12T02:00:00-0400"},
// Daylight savings time 2am EDT (-4) => 1am EST (-5)
{"2012-11-04T00:00:00-0400", "TZ=America/New_York 0 30 2 04 Nov ?", "2012-11-04T02:30:00-0500"},
{"2012-11-04T01:45:00-0400", "TZ=America/New_York 0 30 1 04 Nov ?", "2012-11-04T01:30:00-0500"},
// hourly job
{"2012-11-04T00:00:00-0400", "TZ=America/New_York 0 0 * * * ?", "2012-11-04T01:00:00-0400"},
{"2012-11-04T01:00:00-0400", "TZ=America/New_York 0 0 * * * ?", "2012-11-04T01:00:00-0500"},
{"2012-11-04T01:00:00-0500", "TZ=America/New_York 0 0 * * * ?", "2012-11-04T02:00:00-0500"},
// 1am nightly job (runs twice)
{"2012-11-04T00:00:00-0400", "TZ=America/New_York 0 0 1 * * ?", "2012-11-04T01:00:00-0400"},
{"2012-11-04T01:00:00-0400", "TZ=America/New_York 0 0 1 * * ?", "2012-11-04T01:00:00-0500"},
{"2012-11-04T01:00:00-0500", "TZ=America/New_York 0 0 1 * * ?", "2012-11-05T01:00:00-0500"},
// 2am nightly job
{"2012-11-04T00:00:00-0400", "TZ=America/New_York 0 0 2 * * ?", "2012-11-04T02:00:00-0500"},
{"2012-11-04T02:00:00-0500", "TZ=America/New_York 0 0 2 * * ?", "2012-11-05T02:00:00-0500"},
// 3am nightly job
{"2012-11-04T00:00:00-0400", "TZ=America/New_York 0 0 3 * * ?", "2012-11-04T03:00:00-0500"},
{"2012-11-04T03:00:00-0500", "TZ=America/New_York 0 0 3 * * ?", "2012-11-05T03:00:00-0500"},
// hourly job
{"TZ=America/New_York 2012-11-04T00:00:00-0400", "0 0 * * * ?", "2012-11-04T01:00:00-0400"},
{"TZ=America/New_York 2012-11-04T01:00:00-0400", "0 0 * * * ?", "2012-11-04T01:00:00-0500"},
{"TZ=America/New_York 2012-11-04T01:00:00-0500", "0 0 * * * ?", "2012-11-04T02:00:00-0500"},
// 1am nightly job (runs twice)
{"TZ=America/New_York 2012-11-04T00:00:00-0400", "0 0 1 * * ?", "2012-11-04T01:00:00-0400"},
{"TZ=America/New_York 2012-11-04T01:00:00-0400", "0 0 1 * * ?", "2012-11-04T01:00:00-0500"},
{"TZ=America/New_York 2012-11-04T01:00:00-0500", "0 0 1 * * ?", "2012-11-05T01:00:00-0500"},
// 2am nightly job
{"TZ=America/New_York 2012-11-04T00:00:00-0400", "0 0 2 * * ?", "2012-11-04T02:00:00-0500"},
{"TZ=America/New_York 2012-11-04T02:00:00-0500", "0 0 2 * * ?", "2012-11-05T02:00:00-0500"},
// 3am nightly job
{"TZ=America/New_York 2012-11-04T00:00:00-0400", "0 0 3 * * ?", "2012-11-04T03:00:00-0500"},
{"TZ=America/New_York 2012-11-04T03:00:00-0500", "0 0 3 * * ?", "2012-11-05T03:00:00-0500"},
// Unsatisfiable
{"Mon Jul 9 23:35 2012", "0 0 0 30 Feb ?", ""},
{"Mon Jul 9 23:35 2012", "0 0 0 31 Apr ?", ""},
// Monthly job
{"TZ=America/New_York 2012-11-04T00:00:00-0400", "0 0 3 3 * ?", "2012-12-03T03:00:00-0500"},
// Test the scenario of DST resulting in midnight not being a valid time.
// https://github.com/robfig/cron/issues/157
{"2018-10-17T05:00:00-0400", "TZ=America/Sao_Paulo 0 0 9 10 * ?", "2018-11-10T06:00:00-0500"},
{"2018-02-14T05:00:00-0500", "TZ=America/Sao_Paulo 0 0 9 22 * ?", "2018-02-22T07:00:00-0500"},
}
for _, c := range runs {
sched, err := secondParser.Parse(c.spec)
if err != nil {
t.Error(err)
continue
}
actual := sched.Next(getTime(c.time))
expected := getTime(c.expected)
if !actual.Equal(expected) {
t.Errorf("%s, \"%s\": (expected) %v != %v (actual)", c.time, c.spec, expected, actual)
}
}
}
func TestErrors(t *testing.T) {
invalidSpecs := []string{
"xyz",
"60 0 * * *",
"0 60 * * *",
"0 0 * * XYZ",
}
for _, spec := range invalidSpecs {
_, err := ParseStandard(spec)
if err == nil {
t.Error("expected an error parsing: ", spec)
}
}
}
func getTime(value string) time.Time {
if value == "" {
return time.Time{}
}
var location = time.Local
if strings.HasPrefix(value, "TZ=") {
parts := strings.Fields(value)
loc, err := time.LoadLocation(parts[0][len("TZ="):])
if err != nil {
panic("could not parse location:" + err.Error())
}
location = loc
value = parts[1]
}
var layouts = []string{
"Mon Jan 2 15:04 2006",
"Mon Jan 2 15:04:05 2006",
}
for _, layout := range layouts {
if t, err := time.ParseInLocation(layout, value, location); err == nil {
return t
}
}
if t, err := time.ParseInLocation("2006-01-02T15:04:05-0700", value, location); err == nil {
return t
}
panic("could not parse time value " + value)
}
func TestNextWithTz(t *testing.T) {
runs := []struct {
time, spec string
expected string
}{
// Failing tests
{"2016-01-03T13:09:03+0530", "14 14 * * *", "2016-01-03T14:14:00+0530"},
{"2016-01-03T04:09:03+0530", "14 14 * * ?", "2016-01-03T14:14:00+0530"},
// Passing tests
{"2016-01-03T14:09:03+0530", "14 14 * * *", "2016-01-03T14:14:00+0530"},
{"2016-01-03T14:00:00+0530", "14 14 * * ?", "2016-01-03T14:14:00+0530"},
}
for _, c := range runs {
sched, err := ParseStandard(c.spec)
if err != nil {
t.Error(err)
continue
}
actual := sched.Next(getTimeTZ(c.time))
expected := getTimeTZ(c.expected)
if !actual.Equal(expected) {
t.Errorf("%s, \"%s\": (expected) %v != %v (actual)", c.time, c.spec, expected, actual)
}
}
}
func getTimeTZ(value string) time.Time {
if value == "" {
return time.Time{}
}
t, err := time.Parse("Mon Jan 2 15:04 2006", value)
if err != nil {
t, err = time.Parse("Mon Jan 2 15:04:05 2006", value)
if err != nil {
t, err = time.Parse("2006-01-02T15:04:05-0700", value)
if err != nil {
panic(err)
}
}
}
return t
}
// https://github.com/robfig/cron/issues/144
func TestSlash0NoHang(t *testing.T) {
schedule := "TZ=America/New_York 15/0 * * * *"
_, err := ParseStandard(schedule)
if err == nil {
t.Error("expected an error on 0 increment")
}
}
gitextract_s3rbtqli/ ├── .gitignore ├── .travis.yml ├── LICENSE ├── README.md ├── chain.go ├── chain_test.go ├── constantdelay.go ├── constantdelay_test.go ├── cron.go ├── cron_test.go ├── doc.go ├── go.mod ├── logger.go ├── option.go ├── option_test.go ├── parser.go ├── parser_test.go ├── spec.go └── spec_test.go
SYMBOL INDEX (154 symbols across 13 files)
FILE: chain.go
type JobWrapper (line 11) | type JobWrapper
type Chain (line 15) | type Chain struct
method Then (line 30) | func (c Chain) Then(j Job) Job {
function NewChain (line 20) | func NewChain(c ...JobWrapper) Chain {
function Recover (line 38) | func Recover(logger Logger) JobWrapper {
function DelayIfStillRunning (line 61) | func DelayIfStillRunning(logger Logger) JobWrapper {
function SkipIfStillRunning (line 78) | func SkipIfStillRunning(logger Logger) JobWrapper {
FILE: chain_test.go
function appendingJob (line 12) | func appendingJob(slice *[]int, value int) Job {
function appendingWrapper (line 21) | func appendingWrapper(slice *[]int, value int) JobWrapper {
function TestChain (line 30) | func TestChain(t *testing.T) {
function TestChainRecover (line 44) | func TestChainRecover(t *testing.T) {
type countJob (line 72) | type countJob struct
method Run (line 79) | func (j *countJob) Run() {
method Started (line 89) | func (j *countJob) Started() int {
method Done (line 95) | func (j *countJob) Done() int {
function TestChainDelayIfStillRunning (line 101) | func TestChainDelayIfStillRunning(t *testing.T) {
function TestChainSkipIfStillRunning (line 155) | func TestChainSkipIfStillRunning(t *testing.T) {
FILE: constantdelay.go
type ConstantDelaySchedule (line 7) | type ConstantDelaySchedule struct
method Next (line 25) | func (schedule ConstantDelaySchedule) Next(t time.Time) time.Time {
function Every (line 14) | func Every(duration time.Duration) ConstantDelaySchedule {
FILE: constantdelay_test.go
function TestConstantDelayNext (line 8) | func TestConstantDelayNext(t *testing.T) {
FILE: cron.go
type Cron (line 13) | type Cron struct
method AddFunc (line 141) | func (c *Cron) AddFunc(spec string, cmd func()) (EntryID, error) {
method AddJob (line 148) | func (c *Cron) AddJob(spec string, cmd Job) (EntryID, error) {
method Schedule (line 158) | func (c *Cron) Schedule(schedule Schedule, cmd Job) EntryID {
method Entries (line 177) | func (c *Cron) Entries() []Entry {
method Location (line 189) | func (c *Cron) Location() *time.Location {
method Entry (line 194) | func (c *Cron) Entry(id EntryID) Entry {
method Remove (line 204) | func (c *Cron) Remove(id EntryID) {
method Start (line 215) | func (c *Cron) Start() {
method Run (line 226) | func (c *Cron) Run() {
method run (line 239) | func (c *Cron) run() {
method startJob (line 308) | func (c *Cron) startJob(j Job) {
method now (line 317) | func (c *Cron) now() time.Time {
method Stop (line 323) | func (c *Cron) Stop() context.Context {
method entrySnapshot (line 339) | func (c *Cron) entrySnapshot() []Entry {
method removeEntry (line 347) | func (c *Cron) removeEntry(id EntryID) {
type ScheduleParser (line 30) | type ScheduleParser interface
type Job (line 35) | type Job interface
type Schedule (line 40) | type Schedule interface
type EntryID (line 47) | type EntryID
type Entry (line 50) | type Entry struct
method Valid (line 75) | func (e Entry) Valid() bool { return e.ID != 0 }
type byTime (line 79) | type byTime
method Len (line 81) | func (s byTime) Len() int { return len(s) }
method Swap (line 82) | func (s byTime) Swap(i, j int) { s[i], s[j] = s[j], s[i] }
method Less (line 83) | func (s byTime) Less(i, j int) bool {
function New (line 113) | func New(opts ...Option) *Cron {
type FuncJob (line 134) | type FuncJob
method Run (line 136) | func (f FuncJob) Run() { f() }
FILE: cron_test.go
constant OneSecond (line 17) | OneSecond = 1*time.Second + 50*time.Millisecond
type syncWriter (line 19) | type syncWriter struct
method Write (line 24) | func (sw *syncWriter) Write(data []byte) (n int, err error) {
method String (line 31) | func (sw *syncWriter) String() string {
function newBufLogger (line 37) | func newBufLogger(sw *syncWriter) Logger {
function TestFuncPanicRecovery (line 41) | func TestFuncPanicRecovery(t *testing.T) {
type DummyJob (line 60) | type DummyJob struct
method Run (line 62) | func (d DummyJob) Run() {
function TestJobPanicRecovery (line 66) | func TestJobPanicRecovery(t *testing.T) {
function TestNoEntries (line 86) | func TestNoEntries(t *testing.T) {
function TestStopCausesJobsToNotRun (line 98) | func TestStopCausesJobsToNotRun(t *testing.T) {
function TestAddBeforeRunning (line 116) | func TestAddBeforeRunning(t *testing.T) {
function TestAddWhileRunning (line 134) | func TestAddWhileRunning(t *testing.T) {
function TestAddWhileRunningWithDelay (line 151) | func TestAddWhileRunningWithDelay(t *testing.T) {
function TestRemoveBeforeRunning (line 166) | func TestRemoveBeforeRunning(t *testing.T) {
function TestRemoveWhileRunning (line 185) | func TestRemoveWhileRunning(t *testing.T) {
function TestSnapshotEntries (line 203) | func TestSnapshotEntries(t *testing.T) {
function TestMultipleEntries (line 230) | func TestMultipleEntries(t *testing.T) {
function TestRunningJobTwice (line 255) | func TestRunningJobTwice(t *testing.T) {
function TestRunningMultipleSchedules (line 274) | func TestRunningMultipleSchedules(t *testing.T) {
function TestLocalTimezone (line 297) | func TestLocalTimezone(t *testing.T) {
function TestNonLocalTimezone (line 325) | func TestNonLocalTimezone(t *testing.T) {
function TestStopWithoutStart (line 360) | func TestStopWithoutStart(t *testing.T) {
type testJob (line 365) | type testJob struct
method Run (line 370) | func (t testJob) Run() {
function TestInvalidJobSpec (line 375) | func TestInvalidJobSpec(t *testing.T) {
function TestBlockingRun (line 384) | func TestBlockingRun(t *testing.T) {
function TestStartNoop (line 409) | func TestStartNoop(t *testing.T) {
function TestJob (line 436) | func TestJob(t *testing.T) {
function TestScheduleAfterRemoval (line 490) | func TestScheduleAfterRemoval(t *testing.T) {
type ZeroSchedule (line 538) | type ZeroSchedule struct
method Next (line 540) | func (*ZeroSchedule) Next(time.Time) time.Time {
function TestJobWithZeroTimeDoesNotRun (line 545) | func TestJobWithZeroTimeDoesNotRun(t *testing.T) {
function TestStopAndWait (line 558) | func TestStopAndWait(t *testing.T) {
function TestMultiThreadedStartAndStop (line 674) | func TestMultiThreadedStartAndStop(t *testing.T) {
function wait (line 681) | func wait(wg *sync.WaitGroup) chan bool {
function stop (line 690) | func stop(cron *Cron) chan bool {
function newWithSeconds (line 700) | func newWithSeconds() *Cron {
FILE: logger.go
type Logger (line 19) | type Logger interface
function PrintfLogger (line 28) | func PrintfLogger(l interface{ Printf(string, ...interface{}) }) Logger {
function VerbosePrintfLogger (line 34) | func VerbosePrintfLogger(l interface{ Printf(string, ...interface{}) }) ...
type printfLogger (line 38) | type printfLogger struct
method Info (line 43) | func (pl printfLogger) Info(msg string, keysAndValues ...interface{}) {
method Error (line 52) | func (pl printfLogger) Error(err error, msg string, keysAndValues ...i...
function formatString (line 61) | func formatString(numKeysAndValues int) string {
function formatTimes (line 77) | func formatTimes(keysAndValues []interface{}) []interface{} {
FILE: option.go
type Option (line 8) | type Option
function WithLocation (line 11) | func WithLocation(loc *time.Location) Option {
function WithSeconds (line 19) | func WithSeconds() Option {
function WithParser (line 26) | func WithParser(p ScheduleParser) Option {
function WithChain (line 34) | func WithChain(wrappers ...JobWrapper) Option {
function WithLogger (line 41) | func WithLogger(logger Logger) Option {
FILE: option_test.go
function TestWithLocation (line 10) | func TestWithLocation(t *testing.T) {
function TestWithParser (line 17) | func TestWithParser(t *testing.T) {
function TestWithVerboseLogger (line 25) | func TestWithVerboseLogger(t *testing.T) {
FILE: parser.go
type ParseOption (line 15) | type ParseOption
constant Second (line 18) | Second ParseOption = 1 << iota
constant SecondOptional (line 19) | SecondOptional
constant Minute (line 20) | Minute
constant Hour (line 21) | Hour
constant Dom (line 22) | Dom
constant Month (line 23) | Month
constant Dow (line 24) | Dow
constant DowOptional (line 25) | DowOptional
constant Descriptor (line 26) | Descriptor
type Parser (line 48) | type Parser struct
method Parse (line 88) | func (p Parser) Parse(spec string) (Schedule, error) {
function NewParser (line 71) | func NewParser(options ParseOption) Parser {
function normalizeFields (line 160) | func normalizeFields(fields []string, options ParseOption) ([]string, er...
function ParseStandard (line 229) | func ParseStandard(standardSpec string) (Schedule, error) {
function getField (line 236) | func getField(field string, r bounds) (uint64, error) {
function getRange (line 252) | func getRange(expr string, r bounds) (uint64, error) {
function parseIntOrName (line 321) | func parseIntOrName(expr string, names map[string]uint) (uint, error) {
function mustParseInt (line 331) | func mustParseInt(expr string) (uint, error) {
function getBits (line 344) | func getBits(min, max, step uint) uint64 {
function all (line 360) | func all(r bounds) uint64 {
function parseDescriptor (line 365) | func parseDescriptor(descriptor string, loc *time.Location) (Schedule, e...
FILE: parser_test.go
function TestRange (line 12) | func TestRange(t *testing.T) {
function TestField (line 60) | func TestField(t *testing.T) {
function TestAll (line 80) | func TestAll(t *testing.T) {
function TestBits (line 101) | func TestBits(t *testing.T) {
function TestParseScheduleErrors (line 121) | func TestParseScheduleErrors(t *testing.T) {
function TestParseSchedule (line 140) | func TestParseSchedule(t *testing.T) {
function TestOptionalSecondSchedule (line 184) | func TestOptionalSecondSchedule(t *testing.T) {
function TestNormalizeFields (line 206) | func TestNormalizeFields(t *testing.T) {
function TestNormalizeFields_Errors (line 270) | func TestNormalizeFields_Errors(t *testing.T) {
function TestStandardSpecSchedule (line 315) | func TestStandardSpecSchedule(t *testing.T) {
function TestNoDescriptorParser (line 353) | func TestNoDescriptorParser(t *testing.T) {
function every5min (line 361) | func every5min(loc *time.Location) *SpecSchedule {
function every5min5s (line 365) | func every5min5s(loc *time.Location) *SpecSchedule {
function midnight (line 369) | func midnight(loc *time.Location) *SpecSchedule {
function annual (line 373) | func annual(loc *time.Location) *SpecSchedule {
FILE: spec.go
type SpecSchedule (line 7) | type SpecSchedule struct
method Next (line 58) | func (s *SpecSchedule) Next(t time.Time) time.Time {
type bounds (line 15) | type bounds struct
constant starBit (line 53) | starBit = 1 << 63
function dayMatches (line 179) | func dayMatches(s *SpecSchedule, t time.Time) bool {
FILE: spec_test.go
function TestActivation (line 9) | func TestActivation(t *testing.T) {
function TestNext (line 74) | func TestNext(t *testing.T) {
function TestErrors (line 202) | func TestErrors(t *testing.T) {
function getTime (line 217) | func getTime(value string) time.Time {
function TestNextWithTz (line 248) | func TestNextWithTz(t *testing.T) {
function getTimeTZ (line 275) | func getTimeTZ(value string) time.Time {
function TestSlash0NoHang (line 294) | func TestSlash0NoHang(t *testing.T) {
Condensed preview — 19 files, each showing path, character count, and a content snippet. Download the .json file or copy for the full structured content (102K chars).
[
{
"path": ".gitignore",
"chars": 252,
"preview": "# Compiled Object files, Static and Dynamic libs (Shared Objects)\n*.o\n*.a\n*.so\n\n# Folders\n_obj\n_test\n\n# Architecture spe"
},
{
"path": ".travis.yml",
"chars": 13,
"preview": "language: go\n"
},
{
"path": "LICENSE",
"chars": 1092,
"preview": "Copyright (C) 2012 Rob Figueiredo\nAll Rights Reserved.\n\nMIT LICENSE\n\nPermission is hereby granted, free of charge, to an"
},
{
"path": "README.md",
"chars": 5173,
"preview": "[](http://godoc.org/github.com/robfig/cron)\n[![Build Status]"
},
{
"path": "chain.go",
"chars": 2147,
"preview": "package cron\n\nimport (\n\t\"fmt\"\n\t\"runtime\"\n\t\"sync\"\n\t\"time\"\n)\n\n// JobWrapper decorates the given Job with some behavior.\nty"
},
{
"path": "chain_test.go",
"chars": 6021,
"preview": "package cron\n\nimport (\n\t\"io/ioutil\"\n\t\"log\"\n\t\"reflect\"\n\t\"sync\"\n\t\"testing\"\n\t\"time\"\n)\n\nfunc appendingJob(slice *[]int, valu"
},
{
"path": "constantdelay.go",
"chars": 934,
"preview": "package cron\n\nimport \"time\"\n\n// ConstantDelaySchedule represents a simple recurring duty cycle, e.g. \"Every 5 minutes\".\n"
},
{
"path": "constantdelay_test.go",
"chars": 1906,
"preview": "package cron\n\nimport (\n\t\"testing\"\n\t\"time\"\n)\n\nfunc TestConstantDelayNext(t *testing.T) {\n\ttests := []struct {\n\t\ttime "
},
{
"path": "cron.go",
"chars": 8825,
"preview": "package cron\n\nimport (\n\t\"context\"\n\t\"sort\"\n\t\"sync\"\n\t\"time\"\n)\n\n// Cron keeps track of any number of entries, invoking the "
},
{
"path": "cron_test.go",
"chars": 16581,
"preview": "package cron\n\nimport (\n\t\"bytes\"\n\t\"fmt\"\n\t\"log\"\n\t\"strings\"\n\t\"sync\"\n\t\"sync/atomic\"\n\t\"testing\"\n\t\"time\"\n)\n\n// Many tests sche"
},
{
"path": "doc.go",
"chars": 8308,
"preview": "/*\nPackage cron implements a cron spec parser and job runner.\n\nInstallation\n\nTo download the specific tagged release, ru"
},
{
"path": "go.mod",
"chars": 42,
"preview": "module github.com/robfig/cron/v3\n\ngo 1.12\n"
},
{
"path": "logger.go",
"chars": 2577,
"preview": "package cron\n\nimport (\n\t\"io/ioutil\"\n\t\"log\"\n\t\"os\"\n\t\"strings\"\n\t\"time\"\n)\n\n// DefaultLogger is used by Cron if none is speci"
},
{
"path": "option.go",
"chars": 1081,
"preview": "package cron\n\nimport (\n\t\"time\"\n)\n\n// Option represents a modification to the default behavior of a Cron.\ntype Option fun"
},
{
"path": "option_test.go",
"chars": 867,
"preview": "package cron\n\nimport (\n\t\"log\"\n\t\"strings\"\n\t\"testing\"\n\t\"time\"\n)\n\nfunc TestWithLocation(t *testing.T) {\n\tc := New(WithLocat"
},
{
"path": "parser.go",
"chars": 11337,
"preview": "package cron\n\nimport (\n\t\"fmt\"\n\t\"math\"\n\t\"strconv\"\n\t\"strings\"\n\t\"time\"\n)\n\n// Configuration options for creating a parser. M"
},
{
"path": "parser_test.go",
"chars": 9946,
"preview": "package cron\n\nimport (\n\t\"reflect\"\n\t\"strings\"\n\t\"testing\"\n\t\"time\"\n)\n\nvar secondParser = NewParser(Second | Minute | Hour |"
},
{
"path": "spec.go",
"chars": 4627,
"preview": "package cron\n\nimport \"time\"\n\n// SpecSchedule specifies a duty cycle (to the second granularity), based on a\n// tradition"
},
{
"path": "spec_test.go",
"chars": 10986,
"preview": "package cron\n\nimport (\n\t\"strings\"\n\t\"testing\"\n\t\"time\"\n)\n\nfunc TestActivation(t *testing.T) {\n\ttests := []struct {\n\t\ttime,"
}
]
About this extraction
This page contains the full source code of the robfig/cron GitHub repository, extracted and formatted as plain text for AI agents and large language models (LLMs). The extraction includes 19 files (90.5 KB), approximately 28.7k tokens, and a symbol index with 154 extracted functions, classes, methods, constants, and types. Use this with OpenClaw, Claude, ChatGPT, Cursor, Windsurf, or any other AI tool that accepts text input. You can copy the full output to your clipboard or download it as a .txt file.
Extracted by GitExtract — free GitHub repo to text converter for AI. Built by Nikandr Surkov.