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| (function () { 'use strict';
const EventEmitter = require('events').EventEmitter;
const assert = require('assert');
const dgram = require('dgram');
const fork = require('child_process').fork;
const net = require('net');
const util = require('util');
const SCHED_NONE = 1;
const SCHED_RR = 2;
const uv = process.binding('uv');
const cluster = new EventEmitter();
module.exports = cluster;
cluster.Worker = Worker;
cluster.isWorker = ('NODE_UNIQUE_ID' in process.env);
cluster.isMaster = (cluster.isWorker === false);
function Worker(options) {
if (!(this instanceof Worker))
return new Worker(options);
EventEmitter.call(this);
if (options === null || typeof options !== 'object')
options = {};
this.suicide = undefined;
this.state = options.state || 'none';
this.id = options.id | 0;
if (options.process) {
this.process = options.process;
this.process.on('error', this.emit.bind(this, 'error'));
this.process.on('message', this.emit.bind(this, 'message'));
}
}
util.inherits(Worker, EventEmitter);
Worker.prototype.kill = function() {
this.destroy.apply(this, arguments);
};
Worker.prototype.send = function() {
this.process.send.apply(this.process, arguments);
};
Worker.prototype.isDead = function isDead() {
return this.process.exitCode != null || this.process.signalCode != null;
};
Worker.prototype.isConnected = function isConnected() {
return this.process.connected;
};
// Master/worker specific methods are defined in the *Init() functions.
function SharedHandle(key, address, port, addressType, backlog, fd) {
this.key = key;
this.workers = [];
this.handle = null;
this.errno = 0;
// FIXME(bnoordhuis) Polymorphic return type for lack of a better solution.
var rval;
if (addressType === 'udp4' || addressType === 'udp6')
rval = dgram._createSocketHandle(address, port, addressType, fd);
else
rval = net._createServerHandle(address, port, addressType, fd);
if (typeof rval === 'number')
this.errno = rval;
else
this.handle = rval;
}
SharedHandle.prototype.add = function(worker, send) {
assert(this.workers.indexOf(worker) === -1);
this.workers.push(worker);
send(this.errno, null, this.handle);
};
SharedHandle.prototype.remove = function(worker) {
var index = this.workers.indexOf(worker);
if (index === -1) return false; // The worker wasn't sharing this handle.
this.workers.splice(index, 1);
if (this.workers.length !== 0) return false;
this.handle.close();
this.handle = null;
return true;
};
// Start a round-robin server. Master accepts connections and distributes
// them over the workers.
function RoundRobinHandle(key, address, port, addressType, backlog, fd) {
this.key = key;
this.all = {};
this.free = [];
this.handles = [];
this.handle = null;
this.server = net.createServer(assert.fail);
Iif (fd >= 0)
this.server.listen({ fd: fd });
else if (port >= 0)
this.server.listen(port, address);
else
this.server.listen(address); // UNIX socket path.
var self = this;
this.server.once('listening', function() {
self.handle = self.server._handle;
self.handle.onconnection = self.distribute.bind(self);
self.server._handle = null;
self.server = null;
});
}
RoundRobinHandle.prototype.add = function(worker, send) {
assert(worker.id in this.all === false);
this.all[worker.id] = worker;
var self = this;
function done() {
Eif (self.handle.getsockname) {
var out = {};
self.handle.getsockname(out);
// TODO(bnoordhuis) Check err.
send(null, { sockname: out }, null);
} else {
send(null, null, null); // UNIX socket.
}
self.handoff(worker); // In case there are connections pending.
}
if (this.server === null) return done();
// Still busy binding.
this.server.once('listening', done);
this.server.once('error', function(err) {
// Hack: translate 'EADDRINUSE' error string back to numeric error code.
// It works but ideally we'd have some backchannel between the net and
// cluster modules for stuff like this.
var errno = uv['UV_' + err.errno];
send(errno, null);
});
};
RoundRobinHandle.prototype.remove = function(worker) {
if (worker.id in this.all === false) return false;
delete this.all[worker.id];
var index = this.free.indexOf(worker);
Eif (index !== -1) this.free.splice(index, 1);
if (Object.getOwnPropertyNames(this.all).length !== 0) return false;
for (var handle; handle = this.handles.shift(); handle.close());
this.handle.close();
this.handle = null;
return true;
};
RoundRobinHandle.prototype.distribute = function(err, handle) {
this.handles.push(handle);
var worker = this.free.shift();
Eif (worker) this.handoff(worker);
};
RoundRobinHandle.prototype.handoff = function(worker) {
Iif (worker.id in this.all === false) {
return; // Worker is closing (or has closed) the server.
}
var handle = this.handles.shift();
if (handle === undefined) {
this.free.push(worker); // Add to ready queue again.
return;
}
var message = { act: 'newconn', key: this.key };
var self = this;
sendHelper(worker.process, message, handle, function(reply) {
Eif (reply.accepted)
handle.close();
else
self.distribute(0, handle); // Worker is shutting down. Send to another.
self.handoff(worker);
});
};
if (cluster.isMaster)
masterInit();
else
workerInit();
function masterInit() {
cluster.workers = {};
var intercom = new EventEmitter();
cluster.settings = {};
// XXX(bnoordhuis) Fold cluster.schedulingPolicy into cluster.settings?
var schedulingPolicy = {
'none': SCHED_NONE,
'rr': SCHED_RR
}[process.env.NODE_CLUSTER_SCHED_POLICY];
if (schedulingPolicy === undefined) {
// FIXME Round-robin doesn't perform well on Windows right now due to the
// way IOCP is wired up. Bert is going to fix that, eventually.
schedulingPolicy = (process.platform === 'win32') ? SCHED_NONE : SCHED_RR;
}
cluster.schedulingPolicy = schedulingPolicy;
cluster.SCHED_NONE = SCHED_NONE; // Leave it to the operating system.
cluster.SCHED_RR = SCHED_RR; // Master distributes connections.
// Keyed on address:port:etc. When a worker dies, we walk over the handles
// and remove() the worker from each one. remove() may do a linear scan
// itself so we might end up with an O(n*m) operation. Ergo, FIXME.
var handles = {};
var initialized = false;
cluster.setupMaster = function(options) {
var settings = {
args: process.argv.slice(2),
exec: process.argv[1],
execArgv: process.execArgv,
silent: false
};
settings = util._extend(settings, cluster.settings);
settings = util._extend(settings, options || {});
// Tell V8 to write profile data for each process to a separate file.
// Without --logfile=v8-%p.log, everything ends up in a single, unusable
// file. (Unusable because what V8 logs are memory addresses and each
// process has its own memory mappings.)
Iif (settings.execArgv.some(function(s) { return /^--prof/.test(s); }) &&
!settings.execArgv.some(function(s) { return /^--logfile=/.test(s); }))
{
settings.execArgv = settings.execArgv.concat(['--logfile=v8-%p.log']);
}
cluster.settings = settings;
if (initialized === true)
return process.nextTick(setupSettingsNT, settings);
initialized = true;
schedulingPolicy = cluster.schedulingPolicy; // Freeze policy.
assert(schedulingPolicy === SCHED_NONE || schedulingPolicy === SCHED_RR,
'Bad cluster.schedulingPolicy: ' + schedulingPolicy);
var hasDebugArg = process.execArgv.some(function(argv) {
return /^(--debug|--debug-brk)(=\d+)?$/.test(argv);
});
process.nextTick(setupSettingsNT, settings);
// Send debug signal only if not started in debug mode, this helps a lot
// on windows, because RegisterDebugHandler is not called when node starts
// with --debug.* arg.
Iif (hasDebugArg)
return;
process.on('internalMessage', function(message) {
if (message.cmd !== 'NODE_DEBUG_ENABLED') return;
var key;
for (key in cluster.workers) {
var worker = cluster.workers[key];
if (worker.state === 'online' || worker.state === 'listening') {
process._debugProcess(worker.process.pid);
} else {
worker.once('online', function() {
process._debugProcess(this.process.pid);
});
}
}
});
};
function setupSettingsNT(settings) {
cluster.emit('setup', settings);
}
function createWorkerProcess(id, env) {
var workerEnv = util._extend({}, process.env);
var execArgv = cluster.settings.execArgv.slice();
var debugPort = process.debugPort + id;
var hasDebugArg = false;
workerEnv = util._extend(workerEnv, env);
workerEnv.NODE_UNIQUE_ID = '' + id;
for (var i = 0; i < execArgv.length; i++) {
var match = execArgv[i].match(/^(--debug|--debug-(brk|port))(=\d+)?$/);
Iif (match) {
execArgv[i] = match[1] + '=' + debugPort;
hasDebugArg = true;
}
}
Eif (!hasDebugArg)
execArgv = ['--debug-port=' + debugPort].concat(execArgv);
return fork(cluster.settings.exec, cluster.settings.args, {
env: workerEnv,
silent: cluster.settings.silent,
execArgv: execArgv,
gid: cluster.settings.gid,
uid: cluster.settings.uid
});
}
var ids = 0;
cluster.fork = function(env) {
cluster.setupMaster();
const id = ++ids;
const workerProcess = createWorkerProcess(id, env);
const worker = new Worker({
id: id,
process: workerProcess
});
function removeWorker(worker) {
assert(worker);
delete cluster.workers[worker.id];
if (Object.keys(cluster.workers).length === 0) {
assert(Object.keys(handles).length === 0, 'Resource leak detected.');
intercom.emit('disconnect');
}
}
function removeHandlesForWorker(worker) {
assert(worker);
for (var key in handles) {
var handle = handles[key];
if (handle.remove(worker)) delete handles[key];
}
}
worker.process.once('exit', function(exitCode, signalCode) {
/*
* Remove the worker from the workers list only
* if it has disconnected, otherwise we might
* still want to access it.
*/
if (!worker.isConnected()) removeWorker(worker);
worker.suicide = !!worker.suicide;
worker.state = 'dead';
worker.emit('exit', exitCode, signalCode);
cluster.emit('exit', worker, exitCode, signalCode);
});
worker.process.once('disconnect', function() {
/*
* Now is a good time to remove the handles
* associated with this worker because it is
* not connected to the master anymore.
*/
removeHandlesForWorker(worker);
/*
* Remove the worker from the workers list only
* if its process has exited. Otherwise, we might
* still want to access it.
*/
if (worker.isDead()) removeWorker(worker);
worker.suicide = !!worker.suicide;
worker.state = 'disconnected';
worker.emit('disconnect');
cluster.emit('disconnect', worker);
});
worker.process.on('internalMessage', internal(worker, onmessage));
process.nextTick(emitForkNT, worker);
cluster.workers[worker.id] = worker;
return worker;
};
function emitForkNT(worker) {
cluster.emit('fork', worker);
}
cluster.disconnect = function(cb) {
var workers = Object.keys(cluster.workers);
if (workers.length === 0) {
process.nextTick(intercom.emit.bind(intercom, 'disconnect'));
} else {
for (var key in workers) {
key = workers[key];
if (cluster.workers[key].isConnected())
cluster.workers[key].disconnect();
}
}
if (cb) intercom.once('disconnect', cb);
};
Worker.prototype.disconnect = function() {
this.suicide = true;
send(this, { act: 'disconnect' });
};
Worker.prototype.destroy = function(signo) {
signo = signo || 'SIGTERM';
var proc = this.process;
Eif (this.isConnected()) {
this.once('disconnect', proc.kill.bind(proc, signo));
this.disconnect();
return;
}
proc.kill(signo);
};
function onmessage(message, handle) {
var worker = this;
if (message.act === 'online')
online(worker);
else if (message.act === 'queryServer')
queryServer(worker, message);
else if (message.act === 'listening')
listening(worker, message);
else if (message.act === 'suicide')
worker.suicide = true;
else Eif (message.act === 'close')
close(worker, message);
}
function online(worker) {
worker.state = 'online';
worker.emit('online');
cluster.emit('online', worker);
}
function queryServer(worker, message) {
var args = [message.address,
message.port,
message.addressType,
message.fd];
var key = args.join(':');
var handle = handles[key];
if (handle === undefined) {
var constructor = RoundRobinHandle;
// UDP is exempt from round-robin connection balancing for what should
// be obvious reasons: it's connectionless. There is nothing to send to
// the workers except raw datagrams and that's pointless.
if (schedulingPolicy !== SCHED_RR ||
message.addressType === 'udp4' ||
message.addressType === 'udp6') {
constructor = SharedHandle;
}
handles[key] = handle = new constructor(key,
message.address,
message.port,
message.addressType,
message.backlog,
message.fd);
}
if (!handle.data) handle.data = message.data;
// Set custom server data
handle.add(worker, function(errno, reply, handle) {
reply = util._extend({
errno: errno,
key: key,
ack: message.seq,
data: handles[key].data
}, reply);
if (errno) delete handles[key]; // Gives other workers a chance to retry.
send(worker, reply, handle);
});
}
function listening(worker, message) {
var info = {
addressType: message.addressType,
address: message.address,
port: message.port,
fd: message.fd
};
worker.state = 'listening';
worker.emit('listening', info);
cluster.emit('listening', worker, info);
}
// Round-robin only. Server in worker is closing, remove from list.
function close(worker, message) {
var key = message.key;
var handle = handles[key];
if (handle.remove(worker)) delete handles[key];
}
function send(worker, message, handle, cb) {
sendHelper(worker.process, message, handle, cb);
}
}
function workerInit() {
var handles = {};
// Called from src/node.js
cluster._setupWorker = function() {
var worker = new Worker({
id: +process.env.NODE_UNIQUE_ID | 0,
process: process,
state: 'online'
});
cluster.worker = worker;
process.once('disconnect', function() {
worker.emit('disconnect');
Iif (!worker.suicide) {
// Unexpected disconnect, master exited, or some such nastiness, so
// worker exits immediately.
process.exit(0);
}
});
process.on('internalMessage', internal(worker, onmessage));
send({ act: 'online' });
function onmessage(message, handle) {
if (message.act === 'newconn')
onconnection(message, handle);
else Eif (message.act === 'disconnect')
worker.disconnect();
}
};
// obj is a net#Server or a dgram#Socket object.
cluster._getServer = function(obj, address, port, addressType, fd, cb) {
var message = {
addressType: addressType,
address: address,
port: port,
act: 'queryServer',
fd: fd,
data: null
};
// Set custom data on handle (i.e. tls tickets key)
Iif (obj._getServerData) message.data = obj._getServerData();
send(message, function(reply, handle) {
Iif (obj._setServerData) obj._setServerData(reply.data);
if (handle)
shared(reply, handle, cb); // Shared listen socket.
else
rr(reply, cb); // Round-robin.
});
obj.once('listening', function() {
cluster.worker.state = 'listening';
var address = obj.address();
message.act = 'listening';
message.port = address && address.port || port;
send(message);
});
};
// Shared listen socket.
function shared(message, handle, cb) {
var key = message.key;
// Monkey-patch the close() method so we can keep track of when it's
// closed. Avoids resource leaks when the handle is short-lived.
var close = handle.close;
handle.close = function() {
delete handles[key];
return close.apply(this, arguments);
};
assert(handles[key] === undefined);
handles[key] = handle;
cb(message.errno, handle);
}
// Round-robin. Master distributes handles across workers.
function rr(message, cb) {
if (message.errno)
return cb(message.errno, null);
var key = message.key;
function listen(backlog) {
// TODO(bnoordhuis) Send a message to the master that tells it to
// update the backlog size. The actual backlog should probably be
// the largest requested size by any worker.
return 0;
}
function close() {
// lib/net.js treats server._handle.close() as effectively synchronous.
// That means there is a time window between the call to close() and
// the ack by the master process in which we can still receive handles.
// onconnection() below handles that by sending those handles back to
// the master.
Iif (key === undefined) return;
send({ act: 'close', key: key });
delete handles[key];
key = undefined;
}
function getsockname(out) {
Eif (key) util._extend(out, message.sockname);
return 0;
}
// Faux handle. Mimics a TCPWrap with just enough fidelity to get away
// with it. Fools net.Server into thinking that it's backed by a real
// handle.
var handle = {
close: close,
listen: listen
};
Eif (message.sockname) {
handle.getsockname = getsockname; // TCP handles only.
}
assert(handles[key] === undefined);
handles[key] = handle;
cb(0, handle);
}
// Round-robin connection.
function onconnection(message, handle) {
var key = message.key;
var server = handles[key];
var accepted = server !== undefined;
send({ ack: message.seq, accepted: accepted });
Eif (accepted) server.onconnection(0, handle);
}
Worker.prototype.disconnect = function() {
this.suicide = true;
for (var key in handles) {
var handle = handles[key];
delete handles[key];
handle.close();
}
process.disconnect();
};
Worker.prototype.destroy = function() {
this.suicide = true;
if (!this.isConnected()) process.exit(0);
var exit = process.exit.bind(null, 0);
send({ act: 'suicide' }, exit);
process.once('disconnect', exit);
process.disconnect();
};
function send(message, cb) {
sendHelper(process, message, null, cb);
}
}
var seq = 0;
var callbacks = {};
function sendHelper(proc, message, handle, cb) {
// Mark message as internal. See INTERNAL_PREFIX in lib/child_process.js
message = util._extend({ cmd: 'NODE_CLUSTER' }, message);
if (cb) callbacks[seq] = cb;
message.seq = seq;
seq += 1;
proc.send(message, handle);
}
// Returns an internalMessage listener that hands off normal messages
// to the callback but intercepts and redirects ACK messages.
function internal(worker, cb) {
return function(message, handle) {
if (message.cmd !== 'NODE_CLUSTER') return;
var fn = cb;
if (message.ack !== undefined) {
fn = callbacks[message.ack];
delete callbacks[message.ack];
}
fn.apply(worker, arguments);
};
}
}());
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