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Repository: hseeberger/constructr
Branch: master
Commit: ab10d4ecbb59
Files: 28
Total size: 81.6 KB

Directory structure:
gitextract_n96ddc4r/

├── .gitignore
├── .scalafmt.conf
├── .travis.yml
├── LICENSE
├── NOTICE
├── README.md
├── bin/
│   └── run-etcd.sh
├── build.sbt
├── coordination/
│   └── src/
│       └── main/
│           └── scala/
│               └── de/
│                   └── heikoseeberger/
│                       └── constructr/
│                           └── coordination/
│                               └── Coordination.scala
├── coordination-etcd/
│   └── src/
│       ├── main/
│       │   ├── resources/
│       │   │   └── reference.conf
│       │   └── scala/
│       │       └── de/
│       │           └── heikoseeberger/
│       │               └── constructr/
│       │                   └── coordination/
│       │                       └── etcd/
│       │                           └── EtcdCoordination.scala
│       └── test/
│           └── scala/
│               └── de/
│                   └── heikoseeberger/
│                       └── constructr/
│                           └── coordination/
│                               └── etcd/
│                                   └── EtcdCoordinationSpec.scala
├── core/
│   └── src/
│       ├── main/
│       │   ├── resources/
│       │   │   └── reference.conf
│       │   └── scala/
│       │       └── de/
│       │           └── heikoseeberger/
│       │               └── constructr/
│       │                   ├── Constructr.scala
│       │                   ├── ConstructrExtension.scala
│       │                   ├── ConstructrMachine.scala
│       │                   └── package.scala
│       ├── multi-jvm/
│       │   ├── resources/
│       │   │   ├── application.conf
│       │   │   └── log4j2.xml
│       │   └── scala/
│       │       └── de/
│       │           └── heikoseeberger/
│       │               └── constructr/
│       │                   ├── MultiNodeConstructrSpec.scala
│       │                   └── MultiNodeEtcdConstructrSpec.scala
│       └── test/
│           ├── resources/
│           │   └── application.conf
│           └── scala/
│               └── de/
│                   └── heikoseeberger/
│                       └── constructr/
│                           ├── ConstructrExtensionSpec.scala
│                           ├── ConstructrMachineSpec.scala
│                           └── testutil/
│                               └── CoordinationInfo.scala
├── project/
│   ├── build.properties
│   └── plugins.sbt
└── shell-prompt.sbt

================================================
FILE CONTENTS
================================================

================================================
FILE: .gitignore
================================================
# sbt
lib_managed
project/project
target

# Worksheets (Eclipse or IntelliJ)
*.sc

# Eclipse
.cache*
.classpath
.project
.scala_dependencies
.settings
.target
.worksheet

# IntelliJ
.idea

# ENSIME
.ensime
.ensime_lucene
.ensime_cache

# Mac
.DS_Store

# Akka Persistence
journal
snapshots

# Log files
*.log


================================================
FILE: .scalafmt.conf
================================================
style = defaultWithAlign

danglingParentheses        = true
indentOperator             = spray
maxColumn                  = 100
project.excludeFilters     = [".*\\.sbt"]
rewrite.rules              = [RedundantBraces, RedundantParens, SortImports]
spaces.inImportCurlyBraces = true
unindentTopLevelOperators  = true


================================================
FILE: .travis.yml
================================================
language: scala

scala:
  - 2.11.11
  - 2.12.4

jdk:
  - oraclejdk8

sbt_args: -Dakka.test.timefactor=3.0

sudo: required

services:
  - docker

before_install:
  - docker run
      --detach
      --publish 2379:2379
      quay.io/coreos/etcd:v2.3.7
      --listen-client-urls http://0.0.0.0:2379
      --advertise-client-urls http://127.0.0.1:2379


================================================
FILE: LICENSE
================================================

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================================================
FILE: NOTICE
================================================
Copyright 2015 Heiko Seeberger


================================================
FILE: README.md
================================================
# ConstructR #

[![Join the chat at https://gitter.im/hseeberger/constructr](https://badges.gitter.im/Join%20Chat.svg)](https://gitter.im/hseeberger/constructr?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)

ConstructR is for bootstrapping (construction) an [Akka](http://akka.io) cluster by using a coordination service.

Disambiguation: Despite the similar name, ConstructR is not related to [Lightbend ConductR](http://www.lightbend.com/products/conductr).

ConstructR utilizes a key-value coordination service like etcd to automate bootstrapping or joining a cluster. It stores each member node under the key `/constructr/$clusterName/nodes/$address` where `$clusterName` is for disambiguating multiple clusters and `$address` is a Base64 encoded Akka `Address`. These keys expire after a configurable time in order to avoid stale information. Therefore ConstructR refreshes each key periodically.

In a nutshell, ConstructR is a state machine which first tries to get the nodes from the coordination service. If none are available it tries to acquire a lock, e.g. via a CAS write for etcd, and uses itself or retries getting the nodes. Then it joins using these nodes as seed nodes. After that it adds its address to the nodes and starts the refresh loop:

```
                  ┌───────────────────┐              ┌───────────────────┐
              ┌──▶│   GettingNodes    │◀─────────────│BeforeGettingNodes │
              │   └───────────────────┘    delayed   └───────────────────┘
              │             │     │                            ▲
  join-failed │   non-empty │     └──────────────────────┐     │ failure
              │             ▼               empty        ▼     │
              │   ┌───────────────────┐              ┌───────────────────┐
              └───│      Joining      │◀─────────────│      Locking      │
                  └───────────────────┘    success   └───────────────────┘
                            │
              member-joined │
                            ▼
                  ┌───────────────────┐
                  │    AddingSelf     │
                  └───────────────────┘
                            │     ┌────────────────────────────┐
                            │     │                            │
                            ▼     ▼                            │
                  ┌───────────────────┐              ┌───────────────────┐
                  │ RefreshScheduled  │─────────────▶│    Refreshing     │
                  └───────────────────┘              └───────────────────┘
```

If something goes finally wrong when interacting with the coordination service, e.g. a permanent timeout after a configurable number of retries, ConstructR terminates its `ActorSystem` in the spirit of "fail fast".

``` scala
// All releases including intermediate ones are published here,
// final ones are also published to Maven Central.
resolvers += Resolver.bintrayRepo("hseeberger", "maven")

libraryDependencies ++= Vector(
  "de.heikoseeberger" %% "constructr" % "0.19.0",
  "de.heikoseeberger" %% "constructr-coordination-etcd" % "0.19.0", // in case of using etcd for coordination
  ...
)
```

Simply add the `ConstructrExtension` to the `extensions` configuration setting:

```
akka.extensions = [de.heikoseeberger.constructr.ConstructrExtension]
```

This will start the `Constructr` actor as a system actor. Alternatively start it yourself as early as possible if you feel so inclined.

The following listing shows the available configuration settings with their defaults:

```
constructr {
  coordination {
    host = localhost
    port = 2379
  }

  coordination-timeout    = 3 seconds  // Maximum response time for coordination service (e.g. etcd)
  join-timeout            = 15 seconds // Might depend on cluster size and network properties
  abort-on-join-timeout   = false      // Abort the attempt to join if true; otherwise restart the process from scratch
  max-nr-of-seed-nodes    = 0          // Any nonpositive value means Int.MaxValue
  nr-of-retries           = 2          // Nr. of tries are nr. of retries + 1
  refresh-interval        = 30 seconds // TTL is refresh-interval * ttl-factor
  retry-delay             = 3 seconds  // Give coordination service (e.g. etcd) some delay before retrying
  ttl-factor              = 2.0        // Must be greater or equal 1 + ((coordination-timeout * (1 + nr-of-retries) + retry-delay * nr-of-retries)/ refresh-interval)!
  ignore-refresh-failures = false      // Ignore failures once machine is already in "Refreshing" state. It prevents from FSM being terminated due to exhausted number of retries.

}
```

## Coordination

ConstructR comes with out-of-the-box support for etcd: simply depend on the "constructr-coordination-etcd" module. If you want to use some other coordination backend, e.g. Consul, simply implement the `Coordination` trait from the "constructr-coordination" module and make sure to provide the fully qualified class name via the `constructr.coordination.class-name` configuration setting.

### Community Coordination Implementations

There are some implementations for other coordination backends than etcd:

* [Tecsisa/constructr-consul](https://github.com/Tecsisa/constructr-consul): This library enables to use Consul as cluster coordinator in a ConstructR based cluster.
* [everpeace/constructr-redis](https://github.com/everpeace/constructr-redis): This library enables to use Redis as cluster coordinator in a ConstructR based cluster.
* [typesafehub/constructr-zookeeper](https://github.com/typesafehub/constructr-zookeeper): This library enables to use ZooKeeper as cluster coordinator in a ConstructR based cluster.

## Testing

etcd must be running, e.g.:

```
docker run \
  --detach \
  --name etcd \
  --publish 2379:2379 \
  quay.io/coreos/etcd:v2.3.8 \
  --listen-client-urls http://0.0.0.0:2379 \
  --advertise-client-urls http://192.168.99.100:2379
```

## Contribution policy ##

Contributions via GitHub pull requests are gladly accepted from their original author. Along with any pull requests, please state that the contribution is your original work and that you license the work to the project under the project's open source license. Whether or not you state this explicitly, by submitting any copyrighted material via pull request, email, or other means you agree to license the material under the project's open source license and warrant that you have the legal authority to do so.

Please make sure to follow these conventions:
- For each contribution there must be a ticket (GitHub issue) with a short descriptive name, e.g. "Respect seed-nodes configuration setting"
- Work should happen in a branch named "ISSUE-DESCRIPTION", e.g. "32-respect-seed-nodes"
- Before a PR can be merged, all commits must be squashed into one with its message made up from the ticket name and the ticket id, e.g. "Respect seed-nodes configuration setting (closes #32)"

## License ##

This code is open source software licensed under the [Apache 2.0 License](http://www.apache.org/licenses/LICENSE-2.0.html).


================================================
FILE: bin/run-etcd.sh
================================================
#!/usr/bin/env sh

: ${HOST:=$(ipconfig getifaddr en0)}
: ${HOST:=$(ipconfig getifaddr en1)}
: ${HOST:=$(ipconfig getifaddr en2)}
: ${HOST:=$(ipconfig getifaddr en3)}
: ${HOST:=$(ipconfig getifaddr en4)}
if [ -z $HOST ]; then
  echo HOST neither defined nor detectable!
  exit 1
fi

docker run \
  --detach \
  --name etcd \
  --publish 2379:2379 \
  quay.io/coreos/etcd:v2.3.7 \
  --advertise-client-urls http://${HOST}:2379 \
  --listen-client-urls http://0.0.0.0:2379


================================================
FILE: build.sbt
================================================
// *****************************************************************************
// Projects
// *****************************************************************************

lazy val constructr =
  project
    .in(file("."))
    .enablePlugins(GitVersioning)
    .aggregate(core, coordination, `coordination-etcd`)
    .settings(settings)
    .settings(
      unmanagedSourceDirectories.in(Compile) := Seq.empty,
      unmanagedSourceDirectories.in(Test) := Seq.empty,
      publishArtifact := false
    )

lazy val core =
  project
    .enablePlugins(AutomateHeaderPlugin)
    .configs(MultiJvm)
    .dependsOn(coordination,`coordination-etcd` % "test->compile")
    .settings(settings)
    .settings(multiJvmSettings)
    .settings(
      name := "constructr",
      libraryDependencies ++= Seq(
        library.akkaCluster,
        library.akkaLog4j            % Test,
        library.akkaMultiNodeTestkit % Test,
        library.akkaTestkit          % Test,
        library.log4jCore            % Test,
        library.mockitoCore          % Test,
        library.scalaTest            % Test
      )
    )

lazy val coordination =
  project
    .enablePlugins(AutomateHeaderPlugin)
    .settings(settings)
    .settings(
      name := "constructr-coordination",
      libraryDependencies ++= Seq(
        library.akkaActor
      )
    )

lazy val `coordination-etcd` =
  project
    .enablePlugins(AutomateHeaderPlugin)
    .dependsOn(coordination)
    .settings(settings)
    .settings(
      name := "constructr-coordination-etcd",
      libraryDependencies ++= Seq(
        library.akkaHttp,
        library.akkaStream,
        library.circeParser,
        library.akkaTestkit % Test,
        library.scalaTest   % Test
      )
    )

// *****************************************************************************
// Library dependencies
// *****************************************************************************

lazy val library =
  new {
    object Version {
      final val akka      = "2.5.6"
      final val akkaHttp  = "10.0.10"
      final val akkaLog4j = "1.5.0"
      final val circe     = "0.8.0"
      final val log4j     = "2.9.1"
      final val mockito   = "2.7.22"
      final val scalaTest = "3.0.4"
    }
    val akkaActor            = "com.typesafe.akka"        %% "akka-actor"              % Version.akka
    val akkaCluster          = "com.typesafe.akka"        %% "akka-cluster"            % Version.akka
    val akkaHttp             = "com.typesafe.akka"        %% "akka-http"               % Version.akkaHttp
    val akkaLog4j            = "de.heikoseeberger"        %% "akka-log4j"              % Version.akkaLog4j
    val akkaMultiNodeTestkit = "com.typesafe.akka"        %% "akka-multi-node-testkit" % Version.akka
    val akkaSlf4j            = "com.typesafe.akka"        %% "akka-slf4j"              % Version.akka
    val akkaStream           = "com.typesafe.akka"        %% "akka-stream"             % Version.akka
    val akkaTestkit          = "com.typesafe.akka"        %% "akka-testkit"            % Version.akka
    val circeParser          = "io.circe"                 %% "circe-parser"            % Version.circe
    val log4jCore            = "org.apache.logging.log4j" %  "log4j-core"              % Version.log4j
    val mockitoCore          = "org.mockito"              %  "mockito-core"            % Version.mockito
    val scalaTest            = "org.scalatest"            %% "scalatest"               % Version.scalaTest
}

// *****************************************************************************
// Settings
// *****************************************************************************        |

lazy val settings =
  commonSettings ++
  gitSettings ++
  scalafmtSettings ++
  publishSettings ++
  multiJvmSettings ++
  bintraySettings

lazy val commonSettings =
  Seq(
    // scalaVersion from .travis.yml
    // crossScalaVersions from .travis.yml
    organization := "de.heikoseeberger",
    organizationName := "Heiko Seeberger",
    startYear := Some(2015),
    licenses += ("Apache-2.0", url("http://www.apache.org/licenses/LICENSE-2.0")),
    scalacOptions ++= Seq(
      "-unchecked",
      "-deprecation",
      "-language:_",
      "-target:jvm-1.8",
      "-encoding", "UTF-8"
    ),
    unmanagedSourceDirectories.in(Compile) := Seq(scalaSource.in(Compile).value),
    unmanagedSourceDirectories.in(Test) := Seq(scalaSource.in(Test).value)
)

lazy val gitSettings =
  Seq(
    git.useGitDescribe := true
  )

lazy val scalafmtSettings =
  Seq(
    scalafmtOnCompile := true,
    scalafmtOnCompile.in(Sbt) := false,
    scalafmtVersion := "1.3.0"
  )

lazy val publishSettings =
  Seq(
    homepage := Some(url("https://github.com/hseeberger/constructr")),
    scmInfo := Some(ScmInfo(url("https://github.com/hseeberger/constructr"),
                            "git@github.com:hseeberger/constructr.git")),
    developers += Developer("hseeberger",
                            "Heiko Seeberger",
                            "mail@heikoseeberger.de",
                            url("https://github.com/hseeberger")),
    pomIncludeRepository := (_ => false)
  )

lazy val bintraySettings =
  Seq(
    bintrayPackage := "constructr"
  )

lazy val multiJvmSettings =
  com.typesafe.sbt.SbtMultiJvm.multiJvmSettings ++
  inConfig(MultiJvm)(scalafmtSettings) ++
  headerSettings(MultiJvm) ++
  automateHeaderSettings(MultiJvm) ++
  Seq(
    unmanagedSourceDirectories.in(MultiJvm) := Seq(scalaSource.in(MultiJvm).value),
    test.in(Test) := test.in(MultiJvm).dependsOn(test.in(Test)).value
  )


================================================
FILE: coordination/src/main/scala/de/heikoseeberger/constructr/coordination/Coordination.scala
================================================
/*
 * Copyright 2015 Heiko Seeberger
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package de.heikoseeberger.constructr.coordination

import akka.Done
import akka.actor.{ ActorSystem, Address }
import scala.concurrent.Future
import scala.concurrent.duration.FiniteDuration

object Coordination {

  def apply(clusterName: String, system: ActorSystem): Coordination =
    try {
      val className =
        system.settings.config.getString("constructr.coordination.class-name")
      Class
        .forName(className)
        .getConstructor(classOf[String], classOf[ActorSystem])
        .newInstance(clusterName, system)
        .asInstanceOf[Coordination]
    } catch {
      case _: NoSuchMethodException =>
        throw new Exception(
          """|A Coordination implementation must provide a constructor with the following signature:
             |(clusterName: String, system: ActorSystem)""".stripMargin
        )
    }
}

/**
  * Abstraction for a coordination service. Implementations must provide a constructor with the following signature:
  * `(prefix: String, clusterName: String, system: ActorSystem)`.
  */
trait Coordination {

  /**
    * Get the nodes.
    *
    * @return future of nodes
    */
  def getNodes(): Future[Set[Address]]

  /**
    * Akquire a lock for bootstrapping the cluster (first node).
    *
    * @param self self node
    * @param ttl TTL for the lock
    * @return true, if lock could be akquired, else false
    */
  def lock(self: Address, ttl: FiniteDuration): Future[Boolean]

  /**
    * Add self to the nodes.
    *
    * @param self self node
    * @param ttl TTL for the node entry
    * @return future signaling done
    */
  def addSelf(self: Address, ttl: FiniteDuration): Future[Done]

  /**
    * Refresh entry for self.
    *
    * @param self self node
    * @param ttl TTL for the node entry
    * @return future signaling done
    */
  def refresh(self: Address, ttl: FiniteDuration): Future[Done]
}


================================================
FILE: coordination-etcd/src/main/resources/reference.conf
================================================
constructr {
  coordination {
    class-name = de.heikoseeberger.constructr.coordination.etcd.EtcdCoordination
    host       = localhost
    port       = 2379
  }
}


================================================
FILE: coordination-etcd/src/main/scala/de/heikoseeberger/constructr/coordination/etcd/EtcdCoordination.scala
================================================
/*
 * Copyright 2015 Heiko Seeberger
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package de.heikoseeberger.constructr.coordination
package etcd

import akka.Done
import akka.actor.{ ActorSystem, Address, AddressFromURIString }
import akka.http.scaladsl.Http
import akka.http.scaladsl.client.RequestBuilding.{ Get, Put }
import akka.http.scaladsl.model.StatusCodes.{ Created, NotFound, OK, PreconditionFailed }
import akka.http.scaladsl.model.{ HttpRequest, HttpResponse, ResponseEntity, StatusCode, Uri }
import akka.http.scaladsl.unmarshalling.Unmarshal
import akka.stream.ActorMaterializer
import akka.stream.scaladsl.Sink
import io.circe.Json
import io.circe.parser.parse
import java.nio.charset.StandardCharsets.UTF_8
import java.util.Base64.{ getUrlDecoder, getUrlEncoder }
import scala.concurrent.Future
import scala.concurrent.duration.{ Duration, FiniteDuration }

object EtcdCoordination {

  final case class UnexpectedStatusCode(uri: Uri, statusCode: StatusCode)
      extends RuntimeException(
        s"Unexpected status code $statusCode for URI $uri"
      )

  private def toSeconds(duration: Duration) = (duration.toSeconds + 1).toString
}

final class EtcdCoordination(clusterName: String, system: ActorSystem) extends Coordination {
  import EtcdCoordination._

  private implicit val mat = ActorMaterializer()(system)

  import mat.executionContext

  private val kvUri = {
    val host = system.settings.config.getString("constructr.coordination.host")
    val port = system.settings.config.getInt("constructr.coordination.port")
    Uri(s"http://$host:$port/v2/keys")
  }

  private val baseUri = kvUri.withPath(kvUri.path / "constructr" / clusterName)

  private val nodesUri = baseUri.withPath(baseUri.path / "nodes")

  override def getNodes() = {
    def unmarshalNodes(entity: ResponseEntity) = {
      def toNodes(s: String) = {
        def jsonToNode(json: Json) = {
          val init = nodesUri.path.toString.stripPrefix(kvUri.path.toString)
          val key =
            json.hcursor
              .get[String]("key")
              .fold(throw _, identity)
              .stripPrefix(s"$init/")
          val uri = new String(getUrlDecoder.decode(key), UTF_8)
          AddressFromURIString(uri)
        }
        import cats.syntax.either._ // for Scala 2.11
        parse(s)
          .fold(throw _, identity)
          .hcursor
          .downField("node")
          .get[Set[Json]]("nodes")
          .getOrElse(Set.empty)
          .map(jsonToNode)
      }
      Unmarshal(entity).to[String].map(toNodes)
    }
    responseFor(Get(nodesUri)).flatMap {
      case HttpResponse(OK, _, entity, _) =>
        unmarshalNodes(entity)
      case HttpResponse(NotFound, _, entity, _) =>
        ignore(entity).map(_ => Set.empty)
      case HttpResponse(other, _, entity, _) =>
        ignore(entity).map(_ => throw UnexpectedStatusCode(nodesUri, other))
    }
  }

  override def lock(self: Address, ttl: FiniteDuration) = {
    val lockUri =
      baseUri
        .withPath(baseUri.path / "lock")
        .withQuery(Uri.Query("value" -> self.toString))
    def readLock() = {
      def unmarshalLockHolder(entity: ResponseEntity) = {
        def toLockHolder(s: String) =
          parse(s)
            .fold(throw _, identity)
            .hcursor
            .downField("node")
            .get[String]("value")
            .fold(throw _, identity)
        Unmarshal(entity).to[String].map(toLockHolder)
      }
      responseFor(Get(lockUri)).flatMap {
        case HttpResponse(OK, _, entity, _) =>
          unmarshalLockHolder(entity).map(Some(_))
        case HttpResponse(NotFound, _, entity, _) =>
          ignore(entity).map(_ => None)
        case HttpResponse(other, _, entity, _) =>
          ignore(entity).map(_ => throw UnexpectedStatusCode(nodesUri, other))
      }
    }
    def writeLock() = {
      val uri =
        lockUri.withQuery(
          ("prevExist" -> "false") +: ("ttl" -> toSeconds(ttl)) +:
          Uri.Query(lockUri.rawQueryString)
        )
      responseFor(Put(uri)).flatMap {
        case HttpResponse(Created, _, entity, _) =>
          ignore(entity).map(_ => true)
        case HttpResponse(PreconditionFailed, _, entity, _) =>
          ignore(entity).map(_ => false)
        case HttpResponse(other, _, entity, _) =>
          ignore(entity).map(_ => throw UnexpectedStatusCode(lockUri, other))
      }
    }
    def updateLock(lockHolder: String) = {
      val uri =
        lockUri.withQuery(
          ("prevValue" -> lockHolder) +: ("ttl" -> toSeconds(ttl)) +:
          Uri.Query(lockUri.rawQueryString)
        )
      responseFor(Put(uri)).flatMap {
        case HttpResponse(OK, _, entity, _) =>
          ignore(entity).map(_ => true)
        case HttpResponse(PreconditionFailed, _, entity, _) =>
          ignore(entity).map(_ => false)
        case HttpResponse(other, _, entity, _) =>
          ignore(entity).map(_ => throw UnexpectedStatusCode(lockUri, other))
      }
    }
    readLock().flatMap {
      case Some(h) if h == self.toString => updateLock(h)
      case Some(_)                       => Future.successful(false)
      case None                          => writeLock()
    }
  }

  override def addSelf(self: Address, ttl: FiniteDuration) =
    addSelfOrRefresh(self, ttl)

  override def refresh(self: Address, ttl: FiniteDuration) =
    addSelfOrRefresh(self, ttl)

  private def addSelfOrRefresh(self: Address, ttl: FiniteDuration) = {
    val node  = getUrlEncoder.encodeToString(self.toString.getBytes(UTF_8))
    val query = Uri.Query("ttl" -> toSeconds(ttl), "value" -> self.toString)
    val uri   = nodesUri.withPath(nodesUri.path / node).withQuery(query)
    responseFor(Put(uri)).flatMap {
      case HttpResponse(OK | Created, _, entity, _) =>
        ignore(entity).map(_ => Done)
      case HttpResponse(other, _, entity, _) =>
        ignore(entity).map(_ => throw UnexpectedStatusCode(uri, other))
    }
  }

  private def responseFor(request: HttpRequest) =
    Http(system).singleRequest(request)

  private def ignore(entity: ResponseEntity) =
    entity.dataBytes.runWith(Sink.ignore)
}


================================================
FILE: coordination-etcd/src/test/scala/de/heikoseeberger/constructr/coordination/etcd/EtcdCoordinationSpec.scala
================================================
/*
 * Copyright 2015 Heiko Seeberger
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package de.heikoseeberger.constructr.coordination.etcd

import akka.Done
import akka.actor.{ ActorSystem, AddressFromURIString }
import akka.testkit.{ TestDuration, TestProbe }
import com.typesafe.config.ConfigFactory
import org.scalatest.{ BeforeAndAfterAll, Matchers, WordSpec }
import scala.concurrent.duration.{ Duration, DurationInt, FiniteDuration }
import scala.concurrent.{ Await, Awaitable }
import scala.util.Random

object EtcdCoordinationSpec {

  private val coordinationHost = {
    val dockerHostPattern = """tcp://(\S+):\d{1,5}""".r
    sys.env
      .get("DOCKER_HOST")
      .collect { case dockerHostPattern(address) => address }
      .getOrElse("127.0.0.1")
  }
}

class EtcdCoordinationSpec extends WordSpec with Matchers with BeforeAndAfterAll {
  import EtcdCoordinationSpec._

  private implicit val system = {
    val config =
      ConfigFactory
        .parseString(s"constructr.coordination.host = $coordinationHost")
        .withFallback(ConfigFactory.load())
    ActorSystem("default", config)
  }

  private val address  = AddressFromURIString("akka.tcp://default@a:2552")
  private val address2 = AddressFromURIString("akka.tcp://default@b:2552")

  "EtcdCoordination" should {
    "correctly interact with etcd" in {
      val coordination = new EtcdCoordination(randomString(), system)

      resultOf(coordination.getNodes()) shouldBe 'empty

      resultOf(coordination.lock(address, 10.seconds.dilated)) shouldBe true
      resultOf(coordination.lock(address, 10.seconds.dilated)) shouldBe true
      resultOf(coordination.lock(address2, 10.seconds.dilated)) shouldBe false

      resultOf(coordination.addSelf(address, 10.seconds.dilated)) shouldBe Done
      resultOf(coordination.getNodes()) shouldBe Set(address)

      resultOf(coordination.refresh(address, 1.second.dilated)) shouldBe Done
      resultOf(coordination.getNodes()) shouldBe Set(address)

      val probe = TestProbe()
      probe.within(5.seconds.dilated) { // 2 seconds should be enough, but who knows hows ...
        probe.awaitAssert {
          resultOf(coordination.getNodes()) shouldBe 'empty
        }
      }
    }
  }

  override protected def afterAll() = {
    Await.ready(system.terminate(), Duration.Inf)
    super.afterAll()
  }

  private def resultOf[A](awaitable: Awaitable[A], max: FiniteDuration = 3.seconds.dilated) =
    Await.result(awaitable, max)

  private def randomString() = math.abs(Random.nextInt).toString
}


================================================
FILE: core/src/main/resources/reference.conf
================================================
constructr {
  coordination-timeout    = 3 seconds  // Maximum response time for coordination service (e.g. etcd)
  join-timeout            = 15 seconds // Might depend on cluster size and network properties
  abort-on-join-timeout   = false      // Abort the attempt to join if true; otherwise restart the process from scratch
  max-nr-of-seed-nodes    = 0          // Any nonpositive value means Int.MaxValue
  nr-of-retries           = 2          // Nr. of tries are nr. of retries + 1
  refresh-interval        = 30 seconds // TTL is refresh-interval * ttl-factor
  retry-delay             = 3 seconds  // Give coordination service (e.g. etcd) some delay before retrying
  ttl-factor              = 2.0        // Must be greater or equal 1 + ((coordination-timeout * (1 + nr-of-retries) + retry-delay * nr-of-retries)/ refresh-interval)!
  ignore-refresh-failures = false      // Ignore failures once machine is already in "Refreshing" state. It prevents from FSM being terminated due to exhausted number of retries.
}


================================================
FILE: core/src/main/scala/de/heikoseeberger/constructr/Constructr.scala
================================================
/*
 * Copyright 2015 Heiko Seeberger
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package de.heikoseeberger.constructr

import akka.actor.{ Actor, ActorLogging, ActorRef, Props, SupervisorStrategy, Terminated }
import akka.cluster.{ Cluster, Member }
import akka.cluster.ClusterEvent.{ InitialStateAsEvents, MemberExited, MemberLeft, MemberRemoved }
import akka.cluster.MemberStatus.Up
import de.heikoseeberger.constructr.coordination.Coordination
import scala.concurrent.duration.{ FiniteDuration, NANOSECONDS }

object Constructr {

  final val Name = "constructr"

  def props: Props =
    Props(new Constructr)
}

final class Constructr private extends Actor with ActorLogging {

  override val supervisorStrategy = SupervisorStrategy.stoppingStrategy

  private val cluster = Cluster(context.system)

  if (cluster.settings.SeedNodes.isEmpty) {
    log.info("Creating constructr-machine, because no seed-nodes defined")
    cluster.subscribe(self,
                      InitialStateAsEvents,
                      classOf[MemberLeft],
                      classOf[MemberExited],
                      classOf[MemberRemoved])
    context.become(active(context.watch(createConstructrMachine())))
  } else {
    log.info("Stopping self, because seed-nodes defined")
    context.stop(self)
  }

  override def receive = Actor.emptyBehavior

  private def active(machine: ActorRef): Receive = {
    case Terminated(`machine`) =>
      val selfAddress = cluster.selfAddress
      def isSelfAndUp(member: Member) =
        member.address == selfAddress && member.status == Up
      if (cluster.state.members.exists(isSelfAndUp)) {
        log.error("Leaving, because constructr-machine terminated!")
        cluster.leave(selfAddress)
      } else {
        log.error("Terminating system, because constructr-machine terminated!")
        context.system.terminate()
      }

    case MemberRemoved(member, _) if member.address == cluster.selfAddress =>
      log.error("Terminating system, because member has been removed!")
      context.system.terminate()
  }

  private def createConstructrMachine() = {
    val config = context.system.settings.config
    def getDuration(key: String) =
      FiniteDuration(config.getDuration(key).toNanos, NANOSECONDS)

    val coordinationTimeout   = getDuration("constructr.coordination-timeout")
    val nrOfRetries           = config.getInt("constructr.nr-of-retries")
    val retryDelay            = getDuration("constructr.retry-delay")
    val refreshInterval       = getDuration("constructr.refresh-interval")
    val ttlFactor             = config.getDouble("constructr.ttl-factor")
    val maxNrOfSeedNodes      = config.getInt("constructr.max-nr-of-seed-nodes")
    val joinTimeout           = getDuration("constructr.join-timeout")
    val abortOnJoinTimeout    = config.getBoolean("constructr.abort-on-join-timeout")
    val ignoreRefreshFailures = config.getBoolean("constructr.ignore-refresh-failures")

    context.actorOf(
      ConstructrMachine.props(
        cluster.selfAddress,
        Coordination(context.system.name, context.system),
        coordinationTimeout,
        nrOfRetries,
        retryDelay,
        refreshInterval,
        ttlFactor,
        if (maxNrOfSeedNodes <= 0) Int.MaxValue else maxNrOfSeedNodes,
        joinTimeout,
        abortOnJoinTimeout,
        ignoreRefreshFailures
      ),
      ConstructrMachine.Name
    )
  }
}


================================================
FILE: core/src/main/scala/de/heikoseeberger/constructr/ConstructrExtension.scala
================================================
/*
 * Copyright 2015 Heiko Seeberger
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package de.heikoseeberger.constructr

import akka.actor.{ ExtendedActorSystem, Extension, ExtensionKey }

object ConstructrExtension extends ExtensionKey[ConstructrExtension]

final class ConstructrExtension private (system: ExtendedActorSystem) extends Extension {
  system.systemActorOf(Constructr.props, Constructr.Name)
}


================================================
FILE: core/src/main/scala/de/heikoseeberger/constructr/ConstructrMachine.scala
================================================
/*
 * Copyright 2015 Heiko Seeberger
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package de.heikoseeberger.constructr

import akka.Done
import akka.actor.{ Address, FSM, Props, Status }
import akka.cluster.Cluster
import akka.cluster.ClusterEvent.{ InitialStateAsEvents, MemberJoined, MemberUp }
import akka.pattern.pipe
import akka.stream.ActorMaterializer
import de.heikoseeberger.constructr.coordination.Coordination

import scala.concurrent.duration.{ Duration, FiniteDuration }

object ConstructrMachine {

  implicit class DurationOps(val duration: Duration) extends AnyVal {

    def toFinite: FiniteDuration =
      duration match {
        case Duration(n, unit) => Duration(n, unit)
        case _                 => throw new IllegalStateException("Infinite duration!")
      }
  }

  sealed trait State
  final object State {
    case object BeforeGettingNodes extends State
    case object GettingNodes       extends State
    case object Locking            extends State
    case object Joining            extends State
    case object AddingSelf         extends State
    case object RefreshScheduled   extends State
    case object Refreshing         extends State
    case object RetryScheduled     extends State
  }

  final case class Data(nodes: Set[Address], retryState: State, nrOfRetriesLeft: Int)

  final case class StateTimeoutException(state: State)
      extends RuntimeException(s"State timeout triggered in state $state!")

  final val Name = "constructr-machine"

  def props(
      selfNode: Address,
      coordination: Coordination,
      coordinationTimeout: FiniteDuration,
      coordinationRetries: Int,
      retryDelay: FiniteDuration,
      refreshInterval: FiniteDuration,
      ttlFactor: Double,
      maxNrOfSeedNodes: Int,
      joinTimeout: FiniteDuration,
      abortOnJoinTimeout: Boolean,
      ignoreRefreshFailures: Boolean
  ): Props =
    Props(
      new ConstructrMachine(
        selfNode,
        coordination,
        coordinationTimeout,
        coordinationRetries,
        retryDelay,
        refreshInterval,
        ttlFactor,
        maxNrOfSeedNodes,
        joinTimeout,
        abortOnJoinTimeout,
        ignoreRefreshFailures
      )
    )
}

final class ConstructrMachine(
    val selfNode: Address,
    coordination: Coordination,
    coordinationTimeout: FiniteDuration,
    nrOfRetries: Int,
    retryDelay: FiniteDuration,
    refreshInterval: FiniteDuration,
    ttlFactor: Double,
    maxNrOfSeedNodes: Int,
    joinTimeout: FiniteDuration,
    abortOnJoinTimeout: Boolean,
    ignoreRefreshFailures: Boolean
) extends FSM[ConstructrMachine.State, ConstructrMachine.Data] {
  import ConstructrMachine._
  import context.dispatcher

  require(maxNrOfSeedNodes > 0,
          s"max-nr-of-seed-nodes must be positive, but was $maxNrOfSeedNodes!")
  require(
    ttlFactor >= minTtlFactor,
    s"ttl-factor must be greater or equal 1 + ((coordination-timeout * (1 + nr-of-retries) + retry-delay * nr-of-retries)/ refresh-interval), i.e. $minTtlFactor, but was $ttlFactor!"
  )

  private val cluster = Cluster(context.system)

  startWith(State.GettingNodes, Data(Set.empty, State.GettingNodes, nrOfRetries))

  // Before getting nodes

  when(State.BeforeGettingNodes, retryDelay) {
    case Event(StateTimeout, _) =>
      goto(State.GettingNodes).using(Data(Set.empty, State.GettingNodes, nrOfRetries))
  }

  // Getting nodes

  onTransition {
    case _ -> State.GettingNodes =>
      log.debug("Transitioning to GettingNodes")
      coordination.getNodes().map { nodes =>
        if (nodes.contains(selfNode))
          log.warning(
            s"Selfnode received in list of nodes $nodes. Will filter to prevent forming an island."
          )

        nodes.filterNot(_ == selfNode)
      } pipeTo self
  }

  when(State.GettingNodes, coordinationTimeout) {
    case Event(nodes: Set[Address] @unchecked, _) if nodes.isEmpty =>
      log.debug("Received empty nodes, going to Locking")
      goto(State.Locking)
        .using(stateData.copy(nrOfRetriesLeft = nrOfRetries))

    case Event(nodes: Set[Address] @unchecked, _) =>
      log.debug(s"Received nodes $nodes, going to Joining")
      goto(State.Joining)
        .using(stateData.copy(nodes = nodes, nrOfRetriesLeft = nrOfRetries))

    case Event(Status.Failure(cause), _) =>
      log.warning(s"Failure in $stateName, going to GettingNodes: $cause")
      retry(State.GettingNodes)

    case Event(StateTimeout, _) =>
      log.warning(s"Timeout in $stateName, going to GettingNodes")
      retry(State.GettingNodes)
  }

  // Locking

  onTransition {
    case _ -> State.Locking =>
      log.debug("Transitioning to Locking")
      val ttl = (2 * maxCoordinationTimeout + joinTimeout) * ttlFactor // Keep lock until self added
      coordination.lock(selfNode, ttl.toFinite).pipeTo(self)
  }

  when(State.Locking, coordinationTimeout) {
    case Event(true, _) =>
      log.debug("Successfully locked, going to Joining")
      goto(State.Joining).using(
        stateData.copy(nodes = Set(selfNode), nrOfRetriesLeft = nrOfRetries)
      )

    case Event(false, _) =>
      log.warning("Couldn't acquire lock, going to GettingNodes")
      goto(State.BeforeGettingNodes)

    case Event(Status.Failure(cause), _) =>
      log.warning(s"Failure in $stateName, going to Locking: $cause")
      retry(State.Locking)

    case Event(StateTimeout, _) =>
      log.warning(s"Timeout in $stateName, going to Locking")
      retry(State.Locking)
  }

  // Joining

  onTransition {
    case _ -> State.Joining =>
      log.debug("Transitioning to Joining")
      cluster.joinSeedNodes(seedNodes(nextStateData.nodes)) // An existing seed node process would be stopped
      Cluster(context.system).subscribe(self,
                                        InitialStateAsEvents,
                                        classOf[MemberJoined],
                                        classOf[MemberUp])

  }

  when(State.Joining, joinTimeout) {
    case Event(MemberJoined(member), _) if member.address == selfNode =>
      goto(State.AddingSelf)

    case Event(MemberUp(member), _) if member.address == selfNode =>
      goto(State.AddingSelf)

    case Event(StateTimeout, _) =>
      if (abortOnJoinTimeout)
        stop(FSM.Failure("Timeout in Joining!"))
      else
        goto(State.GettingNodes).using(Data(Set.empty, State.GettingNodes, nrOfRetries))
  }

  onTransition {
    case State.Joining -> _ =>
      log.debug("Transitioning out of Joining")
      cluster.unsubscribe(self)
  }

  private def seedNodes(nodes: Set[Address]) =
    nodes.take(maxNrOfSeedNodes).toVector

  // AddingSelf

  onTransition {
    case _ -> State.AddingSelf =>
      log.debug("Transitioning to AddingSelf")
      coordination
        .addSelf(selfNode, addingSelfOrRefreshingTtl.toFinite)
        .pipeTo(self)
  }

  when(State.AddingSelf, coordinationTimeout) {
    case Event(Done, data) =>
      log.debug("Successfully added self, going to RefreshScheduled")
      goto(State.RefreshScheduled)
        .using(data.copy(nrOfRetriesLeft = nrOfRetries))

    case Event(Status.Failure(cause), _) =>
      log.warning(s"Failure in $stateName, going to AddingSelf: $cause")
      retry(State.AddingSelf)

    case Event(StateTimeout, _) =>
      log.warning(s"Timeout in $stateName, going to AddingSelf")
      retry(State.AddingSelf)
  }

  // RefreshScheduled

  onTransition {
    case _ -> State.RefreshScheduled =>
      log.debug("Transitioning to RefreshScheduled")
  }

  when(State.RefreshScheduled, refreshInterval) {
    case Event(StateTimeout, _) =>
      log.debug(s"Waited for $refreshInterval, going to Refreshing")
      goto(State.Refreshing)
  }

  // Refreshing

  onTransition {
    case _ -> State.Refreshing =>
      log.debug(s"Transitioning to Refreshing")
      coordination
        .refresh(selfNode, addingSelfOrRefreshingTtl.toFinite)
        .pipeTo(self)
  }

  when(State.Refreshing, coordinationTimeout) {
    case Event(Done, _) =>
      log.debug("Successfully refreshed, going to RefreshScheduled")
      goto(State.RefreshScheduled)
        .using(stateData.copy(nrOfRetriesLeft = nrOfRetries))

    case Event(Status.Failure(cause), _) =>
      log.warning(s"Failure in $stateName, going to Refreshing: $cause")
      retryRefreshing()

    case Event(StateTimeout, _) =>
      log.warning(s"Timeout in $stateName, going to Refreshing")
      retryRefreshing()
  }

  // RetryScheduled

  onTransition {
    case state -> State.RetryScheduled =>
      log.debug(s"Transitioning from $state to RetryScheduled")
  }

  when(State.RetryScheduled, retryDelay) {
    case Event(StateTimeout, Data(_, retryState, _)) =>
      log.debug(s"Waited for $retryDelay, going to $retryState")
      goto(retryState)
  }

  // Unhandled events

  whenUnhandled {
    case Event(MemberJoined(member), _) if member.address == selfNode && isPreJoining =>
      goto(State.AddingSelf).using(stateData.copy(nrOfRetriesLeft = nrOfRetries))
    case Event(MemberUp(member), _) if member.address == selfNode && isPreJoining =>
      goto(State.AddingSelf).using(stateData.copy(nrOfRetriesLeft = nrOfRetries))
    // Unsubscribe might be late
    case Event(MemberJoined(_) | MemberUp(_), _) => stay()
  }

  // Initialization

  initialize()

  // Helpers

  private def retry(retryState: ConstructrMachine.State) =
    if (stateData.nrOfRetriesLeft <= 0)
      stop(FSM.Failure(s"Number of retries exhausted in $stateName!"))
    else
      goto(State.RetryScheduled).using(
        stateData.copy(retryState = retryState, nrOfRetriesLeft = stateData.nrOfRetriesLeft - 1)
      )

  private def maxCoordinationTimeout =
    coordinationTimeout * (1 + nrOfRetries) + retryDelay * nrOfRetries

  private def minTtlFactor = 1 + maxCoordinationTimeout / refreshInterval

  private def addingSelfOrRefreshingTtl = refreshInterval * ttlFactor

  private def retryRefreshing() =
    if (ignoreRefreshFailures)
      goto(State.RetryScheduled).using(
        stateData.copy(retryState = State.Refreshing, nrOfRetriesLeft = nrOfRetries)
      )
    else
      retry(State.Refreshing)

  private def isPreJoining: Boolean =
    stateName match {
      case State.BeforeGettingNodes | State.GettingNodes | State.Locking => true
      case _                                                             => false
    }
}


================================================
FILE: core/src/main/scala/de/heikoseeberger/constructr/package.scala
================================================
/*
 * Copyright 2015 Heiko Seeberger
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package de.heikoseeberger

package object constructr {

  type Traversable[+A] = scala.collection.immutable.Traversable[A]
  type Iterable[+A]    = scala.collection.immutable.Iterable[A]
  type Seq[+A]         = scala.collection.immutable.Seq[A]
  type IndexedSeq[+A]  = scala.collection.immutable.IndexedSeq[A]
}


================================================
FILE: core/src/multi-jvm/resources/application.conf
================================================
akka.actor.provider = akka.cluster.ClusterActorRefProvider



================================================
FILE: core/src/multi-jvm/resources/log4j2.xml
================================================
<?xml version="1.0" encoding="UTF-8"?>

<Configuration>
    <Appenders>
        <Console name="STDOUT">
            <PatternLayout>
                <pattern>%date{HH:mm:ss} %-5level %logger{0} [%X{akkaSource}] - %msg%n</pattern>
            </PatternLayout>
        </Console>
        <File name="FILE" fileName="constructr.log" append="false">
            <PatternLayout>
                <pattern>%date{HH:mm:ss} %-5level %logger{0} [%X{akkaSource}] - %msg%n</pattern>
            </PatternLayout>
        </File>
    </Appenders>

    <Loggers>
        <Logger name="de.heikoseeberger.constructr" level="debug" additivity="false">
            <AppenderRef ref="STDOUT"/>
            <AppenderRef ref="FILE"/>
        </Logger>
        <Logger name="Remoting" level="off" additivity="false">
        </Logger>
        <Logger name="akka.remote.EndpointWriter" level="off" additivity="false">
        </Logger>
        <Logger name="akka.cluster.ClusterHeartbeatSender" level="off" additivity="false">
        </Logger>
        <Root level="warn">
            <AppenderRef ref="STDOUT"/>
            <AppenderRef ref="FILE"/>
        </Root>
    </Loggers>
</Configuration>


================================================
FILE: core/src/multi-jvm/scala/de/heikoseeberger/constructr/MultiNodeConstructrSpec.scala
================================================
/*
 * Copyright 2015 Heiko Seeberger
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package de.heikoseeberger.constructr

import akka.actor.ActorDSL.{ actor, Act }
import akka.actor.Address
import akka.cluster.{ Cluster, ClusterEvent }
import akka.http.scaladsl.Http
import akka.http.scaladsl.client.RequestBuilding
import akka.http.scaladsl.model.StatusCodes.{ NotFound, OK }
import akka.http.scaladsl.unmarshalling.Unmarshal
import akka.pattern.ask
import akka.remote.testkit.{ MultiNodeConfig, MultiNodeSpec }
import akka.stream.ActorMaterializer
import akka.testkit.TestDuration
import akka.util.Timeout
import com.typesafe.config.ConfigFactory
import org.scalatest.{ BeforeAndAfterAll, FreeSpecLike, Matchers }
import scala.concurrent.Await
import scala.concurrent.duration.DurationInt

object ConstructrMultiNodeConfig {
  val coordinationHost = {
    val dockerHostPattern = """tcp://(\S+):\d{1,5}""".r
    sys.env
      .get("DOCKER_HOST")
      .collect { case dockerHostPattern(address) => address }
      .getOrElse("127.0.0.1")
  }
}

class ConstructrMultiNodeConfig(coordinationPort: Int) extends MultiNodeConfig {
  import ConstructrMultiNodeConfig._

  commonConfig(ConfigFactory.load())
  for (n <- 1.to(5)) {
    val port = 2550 + n
    nodeConfig(role(port.toString))(
      ConfigFactory.parseString(
        s"""|akka.actor.provider            = akka.cluster.ClusterActorRefProvider
          |akka.remote.netty.tcp.hostname = "127.0.0.1"
          |akka.remote.netty.tcp.port     = $port
          |constructr.coordination.host   = $coordinationHost
          |constructr.coordination.port   = $coordinationPort
          |""".stripMargin
      )
    )
  }
}

abstract class MultiNodeConstructrSpec(
    coordinationPort: Int,
    delete: String,
    get: String,
    toNodes: String => Set[Address]
) extends MultiNodeSpec(new ConstructrMultiNodeConfig(coordinationPort))
    with FreeSpecLike
    with Matchers
    with BeforeAndAfterAll {
  import ConstructrMultiNodeConfig._
  import RequestBuilding._
  import system.dispatcher

  implicit val mat = ActorMaterializer()

  "Constructr should manage an Akka cluster" in {
    runOn(roles.head) {
      within(20.seconds.dilated) {
        awaitAssert {
          val coordinationStatus =
            Await.result(
              Http()
                .singleRequest(
                  Delete(s"http://$coordinationHost:$coordinationPort$delete")
                )
                .map(_.status),
              5.seconds.dilated // As this is the first request fired via `singleRequest`, creating the pool takes some time (probably)
            )
          coordinationStatus should (be(OK) or be(NotFound))
        }
      }
    }

    enterBarrier("coordination-started")

    ConstructrExtension(system)
    val listener = actor(new Act {
      import ClusterEvent._
      var isMember = false
      Cluster(context.system).subscribe(self,
                                        InitialStateAsEvents,
                                        classOf[MemberJoined],
                                        classOf[MemberUp])
      become {
        case "isMember" => sender() ! isMember

        case MemberJoined(member) if member.address == Cluster(context.system).selfAddress =>
          isMember = true

        case MemberUp(member) if member.address == Cluster(context.system).selfAddress =>
          isMember = true
      }
    })
    within(20.seconds.dilated) {
      awaitAssert {
        implicit val timeout = Timeout(1.second.dilated)
        val isMember         = Await.result((listener ? "isMember").mapTo[Boolean], 1.second.dilated)
        isMember shouldBe true
      }
    }

    enterBarrier("cluster-formed")

    within(5.seconds.dilated) {
      awaitAssert {
        val constructrNodes =
          Await.result(
            Http()
              .singleRequest(
                Get(s"http://$coordinationHost:$coordinationPort$get")
              )
              .flatMap(Unmarshal(_).to[String].map(toNodes)),
            1.second.dilated
          )
        val ports = constructrNodes.flatMap(_.port)
        ports shouldBe roles.to[Set].map(_.name.toInt)
      }
    }

    enterBarrier("done")
  }

  override def initialParticipants = roles.size

  override protected def beforeAll() = {
    super.beforeAll()
    multiNodeSpecBeforeAll()
  }

  override protected def afterAll() = {
    multiNodeSpecAfterAll()
    super.afterAll()
  }
}


================================================
FILE: core/src/multi-jvm/scala/de/heikoseeberger/constructr/MultiNodeEtcdConstructrSpec.scala
================================================
/*
 * Copyright 2015 Heiko Seeberger
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package de.heikoseeberger.constructr

import akka.actor.{ Address, AddressFromURIString }
import io.circe.Json
import io.circe.parser.parse
import java.util.Base64

class MultiNodeEtcdConstructrSpecMultiJvmNode1 extends MultiNodeEtcdConstructrSpec
class MultiNodeEtcdConstructrSpecMultiJvmNode2 extends MultiNodeEtcdConstructrSpec
class MultiNodeEtcdConstructrSpecMultiJvmNode3 extends MultiNodeEtcdConstructrSpec
class MultiNodeEtcdConstructrSpecMultiJvmNode4 extends MultiNodeEtcdConstructrSpec
class MultiNodeEtcdConstructrSpecMultiJvmNode5 extends MultiNodeEtcdConstructrSpec

object MultiNodeEtcdConstructrSpec {
  def toNodes(s: String): Set[Address] = {
    def jsonToNode(json: Json) = {
      val key =
        json.hcursor
          .get[String]("key")
          .fold(throw _, identity)
          .stripPrefix("/constructr/MultiNodeConstructrSpec/nodes/")
      AddressFromURIString(new String(Base64.getUrlDecoder.decode(key)))
    }
    import cats.syntax.either._ // for Scala 2.11
    parse(s)
      .fold(throw _, identity)
      .hcursor
      .downField("node")
      .get[Set[Json]]("nodes")
      .getOrElse(Set.empty)
      .map(jsonToNode)
  }
}

abstract class MultiNodeEtcdConstructrSpec
    extends MultiNodeConstructrSpec(
      2379,
      "/v2/keys/constructr?recursive=true",
      "/v2/keys/constructr/MultiNodeConstructrSpec/nodes",
      MultiNodeEtcdConstructrSpec.toNodes
    )


================================================
FILE: core/src/test/resources/application.conf
================================================
akka.actor.provider = akka.cluster.ClusterActorRefProvider



================================================
FILE: core/src/test/scala/de/heikoseeberger/constructr/ConstructrExtensionSpec.scala
================================================
/*
 * Copyright 2015 Heiko Seeberger
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package de.heikoseeberger.constructr

import java.util.UUID

import akka.actor.ActorSystem
import akka.cluster.{ Cluster, MemberStatus }
import com.typesafe.config.ConfigFactory
import de.heikoseeberger.constructr.testutil.CoordinationInfo
import org.scalatest.concurrent.Eventually
import org.scalatest.mockito.MockitoSugar
import org.scalatest.time._
import org.scalatest.{ BeforeAndAfterEach, Matchers, WordSpec }

import scala.concurrent.duration._
import scala.concurrent.{ Await, ExecutionContext, Future }

class ConstructrExtensionSpec
    extends WordSpec
    with Matchers
    with MockitoSugar
    with BeforeAndAfterEach
    with Eventually {

  import ConstructrExtensionSpec._

  private[this] var clusterNodes = Seq.empty[ActorSystem]

  override protected def afterEach(): Unit =
    dispose(clusterNodes)

  "Cluster members managed by ConstructR" should {
    // Happy path
    "successfully join the cluster under normal circumstances" in {
      val clusterName = generateClusterName()
      clusterNodes = 0.until(5).map(i => createClusterNode(clusterName, 15000 + i))
      eventuallyUp(clusterNodes, 10.seconds)
    }

    /*
     * An initial set of nodes joins the cluster and crashes, thus leaving the corresponding seed entries at
     * the backend. A second set of nodes attempts to join the cluster prior to the expiration of the previous
     * seed entries, thus initiating join attempts to seed nodes that are no longer alive. These attempts will
     * continue to fail, until the original seed entries expire, and one of the new nodes manages to register
     * itself as the new seed and formulate a cluster. After that the rest of the nodes will eventually join
     * as well.
     */
    "eventually join the cluster if initial seeds crash" in {
      val clusterName = generateClusterName()
      val basePort    = 15005
      clusterNodes = 0.until(1).map(i => createClusterNode(clusterName, basePort + i))
      eventuallyUp(clusterNodes, 10.seconds)
      dispose(clusterNodes)
      clusterNodes = 1.until(5).map(i => createClusterNode(clusterName, basePort + i))

      Thread.sleep(20.seconds.toMillis)

      for (clusterNode <- clusterNodes) {
        val clusterExtension = Cluster(clusterNode)
        assert(clusterExtension.selfMember.status != MemberStatus.Up,
               s"node ${clusterExtension.selfAddress} is up")
      }

      eventuallyUp(clusterNodes, 40.seconds)
    }

    /*
     * An initial set of nodes joins the cluster and crashes, thus leaving the corresponding seed entries at
     * the backend. A second set of nodes attempts to join the cluster prior to the expiration of the previous
     * seed entries, thus initiating join attempts to seed nodes that are no longer alive. These attempts will
     * continue to fail for a while, until the original set of nodes is restarted, and successfully formulates
     * a cluster. After that the rest of the nodes will eventually join as well.
     */
    "correctly join initial seeds if they crash but recover in time" in {
      val clusterName = generateClusterName()
      val basePort    = 15010
      clusterNodes = 0.until(1).map(i => createClusterNode(clusterName, basePort + i))
      eventuallyUp(clusterNodes, 10.seconds)
      dispose(clusterNodes)
      clusterNodes = 1.until(5).map(i => createClusterNode(clusterName, basePort + i))

      Thread.sleep(10.seconds.toMillis)

      for (clusterNode <- clusterNodes) {
        val clusterExtension = Cluster(clusterNode)
        assert(clusterExtension.selfMember.status != MemberStatus.Up,
               s"node ${clusterExtension.selfAddress} is up")
      }

      clusterNodes = createClusterNode(clusterName, basePort) +: clusterNodes
      eventuallyUp(clusterNodes, 10.seconds)
    }
  }

  private def eventuallyUp(cluster: scala.Seq[ActorSystem], within: FiniteDuration): Unit =
    eventually(timeout(Span(within.toSeconds, Seconds)), interval(Span(2, Seconds))) {
      for (clusterNode <- cluster) {
        val clusterExtension = Cluster(clusterNode)
        assert(clusterExtension.selfMember.status == MemberStatus.Up,
               s"node ${clusterExtension.selfAddress} is not up")
        assert(clusterExtension.state.members.size == cluster.size)
      }
    }
}

object ConstructrExtensionSpec {

  val ClusterNameBase: String = "ConstructrExtensionSpecCluster"

  def generateClusterName(): String = s"$ClusterNameBase-${UUID.randomUUID()}"

  def createClusterNode(name: String, port: Int): ActorSystem = {
    val config = ConfigFactory.parseString(s"""
        | akka {
        |   actor.provider = akka.cluster.ClusterActorRefProvider
        |   cluster.jmx.multi-mbeans-in-same-jvm = on
        |
        |   remote {
        |     netty.tcp {
        |       hostname = "127.0.0.1"
        |       port = $port
        |     }
        |   }
        | }
        |
        | constructr {
        |   coordination {
        |     host = "${CoordinationInfo.host}"
        |     port = ${CoordinationInfo.port}
        |   }
        |
        |   coordination-timeout = 2 seconds
        |   join-timeout = 3 seconds
        |   abort-on-join-timeout = false
        |   nr-of-retries = 1
        |   retry-delay = 2 seconds
        |   refresh-interval = 6 seconds
        | }
      """.stripMargin)
    val system = ActorSystem(name, config)
    ConstructrExtension(system)
    system
  }

  def dispose(clusterNodes: scala.Seq[ActorSystem]): Unit =
    if (clusterNodes.nonEmpty) {
      implicit val executor = ExecutionContext.Implicits.global
      Await.result(Future.traverse(clusterNodes)(_.terminate()), 20.seconds)
    }
}


================================================
FILE: core/src/test/scala/de/heikoseeberger/constructr/ConstructrMachineSpec.scala
================================================
/*
 * Copyright 2015 Heiko Seeberger
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package de.heikoseeberger.constructr

import akka.Done
import akka.actor.{ ActorSystem, Address, FSM, Props }
import akka.cluster.Cluster
import akka.pattern.{ after => delayed }
import akka.stream.ActorMaterializer
import akka.testkit.{ TestDuration, TestProbe }
import de.heikoseeberger.constructr.coordination.Coordination
import org.mockito.Mockito
import org.scalatest.{ BeforeAndAfterAll, Matchers, WordSpec }
import scala.concurrent.duration.{ Duration, DurationInt }
import scala.concurrent.{ Await, Future }

final class ConstructrMachineSpec extends WordSpec with Matchers with BeforeAndAfterAll {
  import ConstructrMachine._
  import Mockito._

  private implicit val system = ActorSystem()
  private implicit val mat    = ActorMaterializer()
  import system.dispatcher

  private val address = Cluster(system).selfAddress

  "ConstructrMachine" should {
    "retry the given number of retries and then fail" in {
      val coordination = mock(classOf[Coordination])
      when(coordination.getNodes()).thenReturn(
        // delay first getNodes call for a bit, so as not to transition out of GettingNodes state too fast
        delayed(50.millis.dilated, system.scheduler)(boom()),
        delayed(1.hour.dilated, system.scheduler)(noNodes())
      )

      val monitor = TestProbe()
      val machine = system.actorOf(
        Props(
          new ConstructrMachine(
            selfNode = address,
            coordination = coordination,
            coordinationTimeout = 100.millis.dilated,
            nrOfRetries = 1,
            retryDelay = 100.millis.dilated,
            refreshInterval = 1.second.dilated,
            ttlFactor = 1.5,
            maxNrOfSeedNodes = 3,
            joinTimeout = 100.millis.dilated,
            abortOnJoinTimeout = false,
            ignoreRefreshFailures = false
          )
        )
      )
      machine ! FSM.SubscribeTransitionCallBack(monitor.ref)
      monitor.watch(machine)

      monitor.expectMsgPF(hint = "Current state GettingNodes") {
        case FSM.CurrentState(_, State.GettingNodes) => ()
      }
      monitor.expectMsgPF(hint = "GettingNodes -> RetryScheduled") {
        case FSM.Transition(_, State.GettingNodes, State.RetryScheduled) => ()
      }
      monitor.expectMsgPF(hint = "RetryScheduled -> GettingNodes") {
        case FSM.Transition(_, State.RetryScheduled, State.GettingNodes) => ()
      }

      monitor.expectTerminated(machine)
    }

    "correctly work down the happy path (including retries)" in {
      val coordination = mock(classOf[Coordination])
      when(coordination.getNodes()).thenReturn(
        delayed(1.hour.dilated, system.scheduler)(noNodes()),
        boom(),
        noNodes(),
        noNodes()
      )
      when(coordination.lock(address, 1650.millis.dilated)).thenReturn(
        delayed(1.hour.dilated, system.scheduler)(boom()),
        boom(),
        Future.successful(false),
        Future.successful(true)
      )
      when(coordination.addSelf(address, 1500.millis.dilated)).thenReturn(
        delayed(1.hour.dilated, system.scheduler)(boom()),
        boom(),
        Future.successful(Done)
      )
      when(coordination.refresh(address, 1500.millis.dilated)).thenReturn(
        delayed(1.hour.dilated, system.scheduler)(boom()),
        boom(),
        Future.successful(Done)
      )

      val monitor = TestProbe()
      val machine = system.actorOf(
        Props(
          new ConstructrMachine(
            selfNode = address,
            coordination = coordination,
            coordinationTimeout = 100.millis.dilated,
            nrOfRetries = 2,
            retryDelay = 100.millis.dilated,
            refreshInterval = 1.second.dilated,
            ttlFactor = 1.5,
            maxNrOfSeedNodes = 3,
            joinTimeout = 100.millis.dilated,
            abortOnJoinTimeout = false,
            ignoreRefreshFailures = false
          )
        )
      )
      machine ! FSM.SubscribeTransitionCallBack(monitor.ref)

      monitor.expectMsgPF(hint = "Current state GettingNodes") {
        case FSM.CurrentState(_, State.GettingNodes) => ()
      }

      monitor.expectMsgPF(hint = "GettingNodes -> RetryScheduled") {
        case FSM.Transition(_, State.GettingNodes, State.RetryScheduled) => ()
      }
      monitor.expectMsgPF(hint = "RetryScheduled -> GettingNodes") {
        case FSM.Transition(_, State.RetryScheduled, State.GettingNodes) => ()
      }
      monitor.expectMsgPF(hint = "GettingNodes -> RetryScheduled") {
        case FSM.Transition(_, State.GettingNodes, State.RetryScheduled) => ()
      }
      monitor.expectMsgPF(hint = "RetryScheduled -> GettingNodes") {
        case FSM.Transition(_, State.RetryScheduled, State.GettingNodes) => ()
      }
      monitor.expectMsgPF(hint = "GettingNodes -> Locking") {
        case FSM.Transition(_, State.GettingNodes, State.Locking) => ()
      }

      monitor.expectMsgPF(hint = "Locking -> RetryScheduled") {
        case FSM.Transition(_, State.Locking, State.RetryScheduled) => ()
      }
      monitor.expectMsgPF(hint = "RetryScheduled -> Locking") {
        case FSM.Transition(_, State.RetryScheduled, State.Locking) => ()
      }
      monitor.expectMsgPF(hint = "Locking -> RetryScheduled") {
        case FSM.Transition(_, State.Locking, State.RetryScheduled) => ()
      }
      monitor.expectMsgPF(hint = "RetryScheduled -> Locking") {
        case FSM.Transition(_, State.RetryScheduled, State.Locking) => ()
      }
      monitor.expectMsgPF(hint = "Locking -> BeforeGettingNodes") {
        case FSM.Transition(_, State.Locking, State.BeforeGettingNodes) => ()
      }
      monitor.expectMsgPF(hint = "BeforeGettingNodes -> GettingNodes") {
        case FSM.Transition(_, State.BeforeGettingNodes, State.GettingNodes) => ()
      }

      monitor.expectMsgPF(hint = "GettingNodes -> Locking") {
        case FSM.Transition(_, State.GettingNodes, State.Locking) => ()
      }

      monitor.expectMsgPF(hint = "Locking -> Joining") {
        case FSM.Transition(_, State.Locking, State.Joining) => ()
      }

      monitor.expectMsgPF(hint = "Joining -> AddingSelf") {
        case FSM.Transition(_, State.Joining, State.AddingSelf) => ()
      }

      monitor.expectMsgPF(hint = "AddingSelf -> RetryScheduled") {
        case FSM.Transition(_, State.AddingSelf, State.RetryScheduled) => ()
      }
      monitor.expectMsgPF(hint = "RetryScheduled -> AddingSelf") {
        case FSM.Transition(_, State.RetryScheduled, State.AddingSelf) => ()
      }
      monitor.expectMsgPF(hint = "AddingSelf -> RetryScheduled") {
        case FSM.Transition(_, State.AddingSelf, State.RetryScheduled) => ()
      }
      monitor.expectMsgPF(hint = "RetryScheduled -> AddingSelf") {
        case FSM.Transition(_, State.RetryScheduled, State.AddingSelf) => ()
      }
      monitor.expectMsgPF(hint = "AddingSelf -> RefreshScheduled") {
        case FSM.Transition(_, State.AddingSelf, State.RefreshScheduled) => ()
      }

      monitor.expectMsgPF(hint = "RefreshScheduled -> Refreshing") {
        case FSM.Transition(_, State.RefreshScheduled, State.Refreshing) => ()
      }

      monitor.expectMsgPF(hint = "Refreshing -> RetryScheduled") {
        case FSM.Transition(_, State.Refreshing, State.RetryScheduled) => ()
      }
      monitor.expectMsgPF(hint = "RetryScheduled -> Refreshing") {
        case FSM.Transition(_, State.RetryScheduled, State.Refreshing) => ()
      }
      monitor.expectMsgPF(hint = "Refreshing -> RetryScheduled") {
        case FSM.Transition(_, State.Refreshing, State.RetryScheduled) => ()
      }
      monitor.expectMsgPF(hint = "RetryScheduled -> Refreshing") {
        case FSM.Transition(_, State.RetryScheduled, State.Refreshing) => ()
      }
      monitor.expectMsgPF(hint = "Refreshing -> RefreshScheduled") {
        case FSM.Transition(_, State.Refreshing, State.RefreshScheduled) => ()
      }
    }

    "machine won't terminate on exceeded number of retries in Refreshing (if it's specified in configuration)" in {
      val coordination = mock(classOf[Coordination])
      when(coordination.getNodes()).thenReturn(
        // delay first getNodes call for a bit, so as not to transition out of GettingNodes state too fast
        delayed(50.millis.dilated, system.scheduler)(noNodes())
      )

      when(coordination.lock(address, 1650.millis.dilated)).thenReturn(
        Future.successful(true)
      )

      when(coordination.addSelf(address, 1500.millis.dilated)).thenReturn(
        Future.successful(Done)
      )

      when(coordination.refresh(address, 1500.millis.dilated)).thenReturn(
        Future.successful(Done),
        delayed(1.hour.dilated, system.scheduler)(boom()),
        boom(),
        boom(),
        Future.successful(Done)
      )

      val nrOfRetries = 2
      val monitor     = TestProbe()
      val machine = system.actorOf(
        Props(
          new ConstructrMachine(
            selfNode = address,
            coordination = coordination,
            coordinationTimeout = 100.millis.dilated,
            nrOfRetries = nrOfRetries,
            retryDelay = 100.millis.dilated,
            refreshInterval = 1.second.dilated,
            ttlFactor = 1.5,
            maxNrOfSeedNodes = 3,
            joinTimeout = 100.millis.dilated,
            abortOnJoinTimeout = false,
            ignoreRefreshFailures = true
          )
        )
      )
      machine ! FSM.SubscribeTransitionCallBack(monitor.ref)

      monitor.expectMsgPF(hint = "Current state GettingNodes") {
        case FSM.CurrentState(_, State.GettingNodes) => ()
      }
      monitor.expectMsgPF(hint = "GettingNodes -> Locking") {
        case FSM.Transition(_, State.GettingNodes, State.Locking) => ()
      }
      monitor.expectMsgPF(hint = "Locking -> Joining") {
        case FSM.Transition(_, State.Locking, State.Joining) => ()
      }
      monitor.expectMsgPF(hint = "Joining -> AddingSelf") {
        case FSM.Transition(_, State.Joining, State.AddingSelf) => ()
      }
      monitor.expectMsgPF(hint = "AddingSelf -> RefreshScheduled") {
        case FSM.Transition(_, State.AddingSelf, State.RefreshScheduled) => ()
      }
      monitor.expectMsgPF(hint = "RefreshScheduled -> Refreshing") {
        case FSM.Transition(_, State.RefreshScheduled, State.Refreshing) => ()
      }

      monitor.expectMsgPF(hint = "Refreshing -> RefreshScheduled") {
        case FSM.Transition(_, State.Refreshing, State.RefreshScheduled) => ()
      }
      monitor.expectMsgPF(hint = "RefreshScheduled -> Refreshing") {
        case FSM.Transition(_, State.RefreshScheduled, State.Refreshing) => ()
      }

      (1 to nrOfRetries + 1) foreach { _ =>
        monitor.expectMsgPF(hint = "Refreshing -> RetryScheduled") {
          case FSM.Transition(_, State.Refreshing, State.RetryScheduled) => ()
        }
        monitor.expectMsgPF(hint = "RetryScheduled -> Refreshing") {
          case FSM.Transition(_, State.RetryScheduled, State.Refreshing) => ()
        }
      }
      monitor.expectMsgPF(hint = "Refreshing -> RefreshScheduled") {
        case FSM.Transition(_, State.Refreshing, State.RefreshScheduled) => ()
      }
    }
  }

  override protected def afterAll(): Unit = {
    Await.ready(system.terminate, Duration.Inf)
    super.afterAll()
  }

  private def boom() = Future.failed(new Exception("BOOM"))

  private def noNodes() = Future.successful(Set.empty[Address])
}


================================================
FILE: core/src/test/scala/de/heikoseeberger/constructr/testutil/CoordinationInfo.scala
================================================
/*
 * Copyright 2015 Heiko Seeberger
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package de.heikoseeberger.constructr.testutil

object CoordinationInfo {

  def host: String = {
    val dockerHostPattern = """tcp://(\S+):\d{1,5}""".r
    sys.env
      .get("DOCKER_HOST")
      .collect({ case dockerHostPattern(address) => address })
      .getOrElse("127.0.0.1")
  }

  def port: Int = 2379

}


================================================
FILE: project/build.properties
================================================
sbt.version = 1.1.1


================================================
FILE: project/plugins.sbt
================================================
addSbtPlugin("com.dwijnand"      % "sbt-travisci"  % "1.1.1")
addSbtPlugin("com.jsuereth"      % "sbt-pgp"       % "1.1.0")
addSbtPlugin("com.lucidchart"    % "sbt-scalafmt"  % "1.14")
addSbtPlugin("com.typesafe.sbt"  % "sbt-git"       % "0.9.3")
addSbtPlugin("com.typesafe.sbt"  % "sbt-multi-jvm" % "0.4.0")
addSbtPlugin("de.heikoseeberger" % "sbt-header"    % "5.0.0")
addSbtPlugin("org.foundweekends" % "sbt-bintray"   % "0.5.1")

libraryDependencies += "org.slf4j" % "slf4j-nop" % "1.7.25"  // Needed by sbt-git


================================================
FILE: shell-prompt.sbt
================================================
shellPrompt.in(ThisBuild) := { state =>
  val project = Project.extract(state).currentRef.project
  s"[$project]> "
}
Download .txt
gitextract_n96ddc4r/

├── .gitignore
├── .scalafmt.conf
├── .travis.yml
├── LICENSE
├── NOTICE
├── README.md
├── bin/
│   └── run-etcd.sh
├── build.sbt
├── coordination/
│   └── src/
│       └── main/
│           └── scala/
│               └── de/
│                   └── heikoseeberger/
│                       └── constructr/
│                           └── coordination/
│                               └── Coordination.scala
├── coordination-etcd/
│   └── src/
│       ├── main/
│       │   ├── resources/
│       │   │   └── reference.conf
│       │   └── scala/
│       │       └── de/
│       │           └── heikoseeberger/
│       │               └── constructr/
│       │                   └── coordination/
│       │                       └── etcd/
│       │                           └── EtcdCoordination.scala
│       └── test/
│           └── scala/
│               └── de/
│                   └── heikoseeberger/
│                       └── constructr/
│                           └── coordination/
│                               └── etcd/
│                                   └── EtcdCoordinationSpec.scala
├── core/
│   └── src/
│       ├── main/
│       │   ├── resources/
│       │   │   └── reference.conf
│       │   └── scala/
│       │       └── de/
│       │           └── heikoseeberger/
│       │               └── constructr/
│       │                   ├── Constructr.scala
│       │                   ├── ConstructrExtension.scala
│       │                   ├── ConstructrMachine.scala
│       │                   └── package.scala
│       ├── multi-jvm/
│       │   ├── resources/
│       │   │   ├── application.conf
│       │   │   └── log4j2.xml
│       │   └── scala/
│       │       └── de/
│       │           └── heikoseeberger/
│       │               └── constructr/
│       │                   ├── MultiNodeConstructrSpec.scala
│       │                   └── MultiNodeEtcdConstructrSpec.scala
│       └── test/
│           ├── resources/
│           │   └── application.conf
│           └── scala/
│               └── de/
│                   └── heikoseeberger/
│                       └── constructr/
│                           ├── ConstructrExtensionSpec.scala
│                           ├── ConstructrMachineSpec.scala
│                           └── testutil/
│                               └── CoordinationInfo.scala
├── project/
│   ├── build.properties
│   └── plugins.sbt
└── shell-prompt.sbt
Condensed preview — 28 files, each showing path, character count, and a content snippet. Download the .json file or copy for the full structured content (89K chars).
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