partner

partner

Wrapping require("child_process") module. Supporting to manage child process status such as start, stop. Handle message, exit status, request/response between parent and child.

Installation

npm install partner

Usage

var partner = require("partner");

partner.on("start", function(data, master){ })

Handling start event.

start start event.

function(data, master) is a callback function.

• data Start argument.
• master false it is child process otherwise callback is invoked from partner.start([data])

partner.on("stop", function(data, master){ })

Handling stop event.

stop stop event.

function(data, master) is a callback function.

• data Stop argument.
• master false it is child process otherwise callback is invoked from partner.stop([data])

partner.on("message", function(message, data, master){ })

Handling message.

message message event.

function(message, data, master) is a callback function.

• message Message name.
• data Data payload
• master false it is child process otherwise callback is invoked from partner.send(message, data, [sendHandle])

partner.on("request", function(message, data, response){ })

Handling request from parent

message message from request.

function(message, data, response) is a callback function.

• message Message name.
• data Data payload
• response Callback function. Invoke to send response to parent.

partner.send(message, data, [sendHandle])

Sending message. If itself is child process then send back to parent, otherwise raise "message" event for itself.

• message Message in string format.
• data Data payload.

partner.broadcast(message, data, [sendHandle])

Sending message for all children process.

• message Message in string format.
• data Data payload.

partner.stop([data])

Sending current process. If itself is child process then do nothing, otherwise raise "stop" event for itself.

• data Optional data payload.

partner.start([data])

Start current process. If itself is child process then do nothing, otherwise raise "start" event for itself.

• data Optional data payload.

partner.list(): Array

List all children process.

partner.create(modulePath): object

Create child process with JavaScript file path. Return new partner object with methods:

var child = partner.create("./child.js");

• child.setOptions(options) set options for child process like: child_process.fork(modulePath, [args], [options]).

• child.getOptions() get options.

• child.setArguments(args) set arguments for child process like: child_process.fork(modulePath, [args], [options]).

• child.getArguments() get arguments.

• child.getFile() get file path.

• child.get() get ChildProcess object.

• child.start(data) start child process with data as argument (optional).

• child.stop(data) stop child process with data as argument (optional).

• child.send(message, data, [sendHandle]) send message to child process with data and sendHandler

• child.request(message, data, function(error, message, data){ }) request child process message and waiting for response in callback.

• child.broadcast(message, data, [sendHandle]) send message to all children process except itself with data and sendHandler.

• child.exit() force child process must stop.

• child.on("message", function(message, data){} ) handle message event is sent back from child.

• child.on("exit", function(data){} ) handle exit event if child is kill or die. Data is start data.

Examples

master.js

var partner = require("partner");
var child = partner.create("master.js");

/* Handle child message. */
child.on("message", function (message, data) {
    /* Go message from child. */
    console.log("[Child::Message]: Got from child: " + (JSON.stringify({
        message: message,
        data: data
    })));
});

/* Handle child exit. */
child.on("exit", function (data) {
    /* Go message from child. */
    console.log("[Child::Exit]: Child is killed. Start again with arguments: " + (JSON.stringify(data)));
    /* Start again. */
    this.start(data);
    console.log("------------------------------");
});

/* Handle start event. */
partner.on("start", function (data, master) {
    if (master) {
        console.log("[Start]: I'm master: " + (JSON.stringify(data)));
        /* Start child if itself is master. */
        child.start("Child::Start");
        /* Send message to child. */
        child.send("Hello", "How are you?");
        console.log("------------------------------");
        /* Stop entry point after 6 second. */
        setTimeout(function () {
            console.log("------------------------------");
            partner.stop("Master::Stop");
        }, 3000);
        /* Kill child after 2 second. */
        setTimeout(function () {
            console.log("------------------------------");
            console.log("            child.get().kill()");
            child.get().kill();
        }, 2000);
    } else {
        console.log("[Start]: I'm child: " + (JSON.stringify(data)));
        /* Send to itself . */
        console.log("------------------------------");
        partner.send("???", "Who am I?");
    }
});

/* Handle stop event. */
partner.on("stop", function (data, master) {
    if (master) {
        /* Stop child if itself is master. */
        child.stop("Child::Stop");
        console.log("[Stop]: I'm master: " + (JSON.stringify(data)));
        /* Stop child after 1 second. */
        setTimeout(function () {
            console.log("------------------------------");
            console.log("            child.stop('Child::Stop')");
            child.stop("Child::Stop");
        }, 2000);
        /* Force kill child after 3 second. */
        setTimeout(function () {
            console.log("------------------------------");
            console.log("            child.exit()");
            child.exit();
        }, 3000);
    } else {
        console.log("[Stop]: I'm child: " + (JSON.stringify(data)));
    }
});

/* Handle stop event. */
partner.on("message", function (message, data, master) {
    if (master) {
        console.log("[Message]: Got from itself: " + (JSON.stringify({
            message: message,
            data: data
        })));
    } else {
        console.log("[Message]: Got from parent: " + (JSON.stringify({
            message: message,
            data: data
        })));
    }
});

/* Start entry point. */
partner.start("Master::Start");

TODO

License

MIT