├── .gitignore
├── README.md
├── bin
    ├── service.bash
    └── start-scheduler.bash
├── pom.xml
└── src
    └── main
        └── scala
            └── mesosphere
                └── mesos_scala
                    ├── ExampleScheduler.scala
                    └── Main.scala


/.gitignore:
--------------------------------------------------------------------------------
1 | .idea
2 | target
3 | *.iml
4 | 


--------------------------------------------------------------------------------
/README.md:
--------------------------------------------------------------------------------
 1 | # Mesos Getting Started Tutorial
 2 | 
 3 | This tutorial explains how to build a simple distributed fault-tolerant framework on top of Mesos.
 4 | The example framework can launch a given number of instances of a command across a cluster,
 5 | and will restart the command if it fails.
 6 | 
 7 | ## Prerequisites
 8 | 
 9 | ### Install Autotools and Libtool
10 | 
11 | Mesos uses autotools to build. Install via Homebrew on a Mac:
12 | 
13 |     brew install autoconf automake libtool
14 | 
15 | ### Install Mesos
16 | 
17 | The Mesos repo on Github is currently out of sync. You can use the one below for now.
18 | 
19 |     git clone https://git-wip-us.apache.org/repos/asf/incubator-mesos.git
20 |     cd incubator-mesos
21 |     ./bootstrap
22 |     mkdir build
23 |     cd build
24 |     ../configure
25 |     make
26 |     make install
27 | 
28 | ### Run Zookeeper and Mesos
29 | 
30 | Mesos ships with Zookeeper. Run these commands in different terminal windows to start a local Zookeeper, Mesos master, and Mesos slave.
31 | 
32 |     cd /path/to/incubator-mesos/build/third_party/zookeeper-3.3.4
33 |     cp conf/zoo_sample.cfg conf/zoo.cfg
34 |     ./bin/zkServer.sh start
35 | 
36 |     /usr/local/sbin/mesos-master --zk=zk://localhost:2181/mesos
37 | 
38 |     /usr/local/sbin/mesos-slave --master=zk://localhost:2181/mesos
39 | 
40 | ### Add the Mesos JAR to your local Maven Repo
41 | 
42 |     mvn install:install-file -Dfile=/path/to/incubator-mesos/build/src/mesos-0.13.0.jar -DgroupId=org.apache.mesos -DartifactId=mesos -Dversion=0.13.0 -Dpackaging=jar


--------------------------------------------------------------------------------
/bin/service.bash:
--------------------------------------------------------------------------------
1 | #!/bin/bash
2 | 
3 | while true; do
4 |   echo "$(date) pid $$ running on $MESOS_SLAVE_ID" >> /tmp/mesos-sample-service.out
5 |   sleep 10
6 | done
7 | 


--------------------------------------------------------------------------------
/bin/start-scheduler.bash:
--------------------------------------------------------------------------------
 1 | #!/bin/bash
 2 | 
 3 | if [ -z ${MESOS_HOME+x} ]
 4 | then
 5 |   echo "MESOS_HOME is not set. Defaulting to /usr/local"
 6 |   MESOS_HOME='/usr/local'
 7 | else
 8 |   echo "MESOS_HOME is set to: $MESOS_HOME"
 9 | fi
10 | 
11 | export MESOS_NATIVE_LIBRARY=$(find "$MESOS_HOME" -name libmesos.dylib -or -name libmesos.so | head -n1)
12 | echo "MESOS_NATIVE_LIBRARY set to $MESOS_NATIVE_LIBRARY"
13 | 
14 | FRAMEWORK_HOME=$(dirname $0)/../
15 | 
16 | # Start the scheduler
17 | java -cp $FRAMEWORK_HOME/target/mesos-getting-started-*.jar mesosphere.mesos_scala.Main $@
18 | 


--------------------------------------------------------------------------------
/pom.xml:
--------------------------------------------------------------------------------
 1 | <?xml version="1.0" encoding="UTF-8"?>
 2 | <project xmlns="http://maven.apache.org/POM/4.0.0"
 3 |          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 4 |          xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
 5 |   <modelVersion>4.0.0</modelVersion>
 6 | 
 7 |   <groupId>mesosphere</groupId>
 8 |   <artifactId>mesos-getting-started</artifactId>
 9 |   <version>0.1-SNAPSHOT</version>
10 | 
11 |   <properties>
12 |     <scala.version>2.10.1</scala.version>
13 |     <mesos.version>0.14.0</mesos.version>
14 |     <protobuf.version>2.4.1</protobuf.version>
15 |   </properties>
16 | 
17 |   <dependencies>
18 | 
19 |     <dependency>
20 |       <groupId>org.scala-lang</groupId>
21 |       <artifactId>scala-library</artifactId>
22 |       <version>${scala.version}</version>
23 |     </dependency>
24 | 
25 |     <dependency>
26 |       <groupId>org.apache.mesos</groupId>
27 |       <artifactId>mesos</artifactId>
28 |       <version>${mesos.version}</version>
29 |     </dependency>
30 | 
31 |     <dependency>
32 |       <groupId>com.google.protobuf</groupId>
33 |       <artifactId>protobuf-java</artifactId>
34 |       <version>${protobuf.version}</version>
35 |     </dependency>
36 | 
37 |   </dependencies>
38 | 
39 |   <repositories>
40 |     <repository>
41 |       <id>mesosphere-public-repo</id>
42 |       <name>Mesosphere Public Repo</name>
43 |       <url>http://s3.amazonaws.com/mesosphere-maven-public/</url>
44 |     </repository>
45 |   </repositories>
46 | 
47 |   <build>
48 |     <plugins>
49 |       <plugin>
50 |         <groupId>org.apache.maven.plugins</groupId>
51 |         <artifactId>maven-shade-plugin</artifactId>
52 |         <version>2.0</version>
53 |         <configuration>
54 |           <filters>
55 |             <filter>
56 |               <artifact>*:*</artifact>
57 |               <excludes>
58 |                 <exclude>META-INF/*.SF</exclude>
59 |                 <exclude>META-INF/*.DSA</exclude>
60 |                 <exclude>META-INF/*.RSA</exclude>
61 |               </excludes>
62 |             </filter>
63 |           </filters>
64 |         </configuration>
65 |         <executions>
66 |           <execution>
67 |             <phase>package</phase>
68 |             <goals>
69 |               <goal>shade</goal>
70 |             </goals>
71 |           </execution>
72 |         </executions>
73 |       </plugin>
74 | 
75 |       <plugin>
76 |         <groupId>org.scala-tools</groupId>
77 |         <artifactId>maven-scala-plugin</artifactId>
78 |         <version>2.15.2</version>
79 |         <executions>
80 |           <execution>
81 |             <goals>
82 |               <goal>compile</goal>
83 |               <goal>testCompile</goal>
84 |             </goals>
85 |           </execution>
86 |         </executions>
87 |         <configuration>
88 |           <scalaVersion>${scala.version}</scalaVersion>
89 |         </configuration>
90 |       </plugin>
91 |     </plugins>
92 |   </build>
93 | 
94 | </project>
95 | 


--------------------------------------------------------------------------------
/src/main/scala/mesosphere/mesos_scala/ExampleScheduler.scala:
--------------------------------------------------------------------------------
  1 | package mesosphere.mesos_scala
  2 | 
  3 | import org.apache.mesos.{SchedulerDriver, Scheduler}
  4 | import org.apache.mesos.Protos._
  5 | import java.util
  6 | import java.util.logging.Logger
  7 | import org.apache.mesos.state.State
  8 | 
  9 | /**
 10 |  * A Mesos framework scheduler that runs a given number of instances of a command across a cluster.
 11 |  *
 12 |  * @author Tobi Knaup
 13 |  */
 14 | 
 15 | class ExampleScheduler(command: String, numInstances: Int, state: State) extends Scheduler {
 16 | 
 17 |   val log = Logger.getLogger(getClass.getName)
 18 |   val currentInstancesStateName = "currentInstances"
 19 |   // Keep track of how many instances are currently running
 20 |   var currentInstances = fetchCurrentInstances()
 21 | 
 22 |   def registered(driver: SchedulerDriver, p2: FrameworkID, p3: MasterInfo) {}
 23 | 
 24 |   def reregistered(driver: SchedulerDriver, p2: MasterInfo) {}
 25 | 
 26 |   def resourceOffers(driver: SchedulerDriver, offers: util.List[Offer]) {
 27 |     import scala.collection.JavaConversions._
 28 | 
 29 |     for (offer <- offers) {
 30 |       log.info("Received offer " + offer)
 31 | 
 32 |       if (currentInstances < numInstances) {
 33 |         val taskId = TaskID.newBuilder
 34 |           .setValue("task_" + System.currentTimeMillis())
 35 | 
 36 |         val cpuResource = Resource.newBuilder
 37 |           .setName("cpus")
 38 |           .setType(Value.Type.SCALAR)
 39 |           .setScalar(Value.Scalar.newBuilder().setValue(1))
 40 | 
 41 |         val commandInfo = CommandInfo.newBuilder
 42 |           .setValue(command)
 43 | 
 44 |         val task = TaskInfo.newBuilder
 45 |           .setName(taskId.getValue)
 46 |           .setTaskId(taskId)
 47 |           .setSlaveId(offer.getSlaveId)
 48 |           .addResources(cpuResource)
 49 |           .setCommand(commandInfo)
 50 |           .build
 51 | 
 52 |         log.info("Launching task " + taskId.getValue)
 53 |         driver.launchTasks(offer.getId, List(task))
 54 |         currentInstances += 1
 55 |         storeCurrentInstances()
 56 |       } else {
 57 |         log.info("Declining offer")
 58 |         driver.declineOffer(offer.getId)
 59 |       }
 60 |     }
 61 |   }
 62 | 
 63 |   def offerRescinded(driver: SchedulerDriver, p2: OfferID) {}
 64 | 
 65 |   def statusUpdate(driver: SchedulerDriver, status: TaskStatus) {
 66 |     log.info("Received status update " + status)
 67 | 
 68 |     if (status.getState.eq(TaskState.TASK_FAILED)) {
 69 |       currentInstances -= 1
 70 |       storeCurrentInstances()
 71 |     }
 72 |   }
 73 | 
 74 |   def frameworkMessage(driver: SchedulerDriver, executor: ExecutorID, slave: SlaveID, p4: Array[Byte]) {}
 75 | 
 76 |   def disconnected(driver: SchedulerDriver) {}
 77 | 
 78 |   def slaveLost(driver: SchedulerDriver, slave: SlaveID) {}
 79 | 
 80 |   def executorLost(driver: SchedulerDriver, executor: ExecutorID, slave: SlaveID, p4: Int) {}
 81 | 
 82 |   def error(driver: SchedulerDriver, error: String) {}
 83 | 
 84 |   private def fetchCurrentInstances(): Int = {
 85 |     val bytes = state.fetch(currentInstancesStateName).get.value
 86 | 
 87 |     val count = if (bytes.length > 0) {
 88 |       bytes(0).toInt
 89 |     } else {
 90 |       0
 91 |     }
 92 | 
 93 |     log.info("Fetched current instance count " + count)
 94 |     count
 95 |   }
 96 | 
 97 |   private def storeCurrentInstances(): Unit = {
 98 |     val oldVar = state.fetch(currentInstancesStateName).get
 99 |     val data = Array(currentInstances.toByte)
100 |     val newVar = state.store(oldVar.mutate(data))
101 | 
102 |     if (data.sameElements(newVar.get.value)) {
103 |       log.info("Successfully stored current instance count " + currentInstances)
104 |     } else {
105 |       log.warning("Failed to store current instance count")
106 |     }
107 |   }
108 | }
109 | 


--------------------------------------------------------------------------------
/src/main/scala/mesosphere/mesos_scala/Main.scala:
--------------------------------------------------------------------------------
 1 | package mesosphere.mesos_scala
 2 | 
 3 | import org.apache.mesos.MesosSchedulerDriver
 4 | import org.apache.mesos.Protos._
 5 | import org.apache.mesos.state.ZooKeeperState
 6 | import java.util.concurrent.TimeUnit
 7 | 
 8 | /**
 9 |  * @author Tobi Knaup
10 |  */
11 | 
12 | object Main extends App {
13 |   // Every Mesos framework needs a name
14 |   val frameworkName = "mesos_scala-0.0.1"
15 |   // URL of the Mesos master
16 |   val master = args(0)
17 |   // The command to run
18 |   val command = args(1)
19 |   // Number of instances to run
20 |   val numInstances = args(2).toInt
21 | 
22 |   // FrameworkID uniquely identifies a framework and can be used for failover
23 |   val frameworkId = FrameworkID.newBuilder
24 |     .setValue(frameworkName)
25 |     .build
26 |   // FrameworkInfo describes a framework
27 |   val frameworkInfo = FrameworkInfo.newBuilder
28 |     .setName(frameworkName)
29 |     .setId(frameworkId)
30 |     .setUser("") // Let Mesos assign the user
31 |     .setFailoverTimeout(60.0) // Allow a 60 second window for failover
32 |     .build
33 | 
34 |   // Create a state object backed by ZK
35 |   val state = new ZooKeeperState("localhost:2181", 10, TimeUnit.SECONDS, "/getting-started-state")
36 |   // Create the scheduler, the driver, and run it
37 |   val scheduler = new ExampleScheduler(command, numInstances, state)
38 |   val driver = new MesosSchedulerDriver(scheduler, frameworkInfo, master)
39 |   driver.run()
40 | }


--------------------------------------------------------------------------------