A simple wrapper over node cluster for zero-downtime reloads
npm install herdHerd your child processes! A simple wrapper over node cluster for zero-downtime reloads.
Just pass herd the function to run on the child-processes.
``javascript
var http = require('http');
var herd = require('herd');
herd('server')
.run(function (){
http.createServer.listen(8000);
});
`
From the terminal, send a SIGHUP signal to gracefully reload the process:
`shell`
$ kill -1 1922
We usually keep the master process really small, and never restart it. By default the process will exit after 1 second, but close handlers and custom timeouts can be specified as well.
#### Herd(name)
Create a new herd with title name
#### .timeout(ms)
Set the timeout before killing a worker in ms. (defaults to 1 second if you don't specify a close handler, otherwise none).
#### .server(isServer)
By default, new processes will not be created until a listening event is emitted by the child process (which is the default for _servers_). Call this flag if you'd rather wait for online event, in the case of your workers which might not ever call net.Server.listen.
#### .size(workers)
Set the number of workers to spawn. Defaults to the number of cpus.
#### .close(fn)
Calls the fn as the worker is as part of the exit handler. Which can be used to perform some type of cleanup before exiting. If a timeout is also specified, the process will exit whenever the first condition is triggered.
`js
/**
* Flush our remaining messages to disk.
*/
function close(fn){
flush(msgs, fn);
}
herd()
.close(close)
.run(run);
``
(The MIT License)
Copyright (c) 2012 Segment.io <friends@segment.io>
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