PerfectHadoop: YARN Node Manager

This project provides a Swift wrapper of YARN Node Manager REST API:

• YARNNodeManager(): access to all Applications and Containers information of a YARN manager

Connect to YARN Node Manager

To connect to your Hadoop YARN Node Manager by Perfect, initialize a YARNNodeManager() object with sufficient parameters:

// this connection could possibly do some basic operations
let nm = YARNNodeManager(host: "yarnNodeManager.somehadoopdomain.com", port: 8042)

or connect to Hadoop YARN Node Manager with a valid user name:

// add user name if need
let nm = YARNNodeManager(host: "yarnNodeManager.somehadoopdomain.com", port: 8042, user: "your user name")

Authentication

If using Kerberos to authenticate, please try codes below:

// set auth to kerberos
let yarn = YARNNodeManager(host: "yarnNodeManager.somehadoopdomain.com", port: 8042, user: "username", auth: .krb5)

Parameters of YARNNodeManager Object

Get General Information

Call checkOverall() to get the general information of a YARN node manager in form of a YARNNodeManager.Info structure:

guard let inf = try yarn.checkOverall() else {
    // something goes wrong here
}
print(inf.id)
print(inf.nodeHostName)
print(inf.healthReport)

Members of YARNNodeManager.NodeInfo

Applications

Call checkApps() to return an array of APP structure. With the Applications API, you can obtain a collection of resources, each of which represents an application.

let apps = try yarn.checkApps()
apps.forEach { a in
  print(a.id)
  print(a.containerids)
  print(a.state)
}//next

Data Structure of APP

Check A Specific Application

If an application id is available, you can call checkApp() to query information on nodes:

guard let app = try yarn.checkApp("application_1326121700862_0005") else {
    // something wrong
    print("check app failed")
    return
}
// print out all container ids of the application
print(app.containerids)

checkApp() will return an APP object, as described above.

Check Containers

Call checkContainers() to check all containers on the current node:

// get all containers
let containers = try ynode.checkContainers()

// check how many containers on node
print(containers.count)

containers.forEach { container in
    print(container.id)
    print(container.state)
    print(container.nodeId)
    print(container.diagnostics)
    /// ...
}

checkContainers() returns an array of Container structure, as described below:

Container Object

Check a Specific Container

If a container id is available, you can also use checkContainer() to check a specific container:

guard let container = try ynode.checkContainer(id: container.id) else {
    // checking container failed
}
print(container.id)
print(container.state)
print(container.nodeId)
print(container.diagnostics)

This method will return a Container object as described above.