Simple worker queue implemention with combination of redis pub-sub and worker-farm.
beygir depends on Worker Farm, a very simple useful and stable child process controller package. (Available in npm with name node-worker-farm). On start up beygir subscribes to redis pubsub channels that will enqueue tasks to workers.
beygir is available in npm
$ npm install beygirInstantiate beygir by requiring package
var beygir = require('beygir');Then start service by calling start with configuration object
beygir.start({
//keys in configuration is used as Redis pubsub channel name
'worker_queue' : {
/* worker property contains path to js file to be run in
* child process see next section for worker function */
worker: require.resolve('path/for/worker/task/js_file'),
callback: function some_function(error, result){
/* this function is provided as last argument to worker
* function */
},
options: {
/* options passed to worker-farm function directly */
/* see worker-farm for details */
}
},
'task_*': {
/* to subscribe to a pattern for channel name you need to
* set pattern property to true */
pattern: true,
worker: require.resolve('another/worker/task/js_file')
/* callback and options properties are not required */
}
})If you need to trigger a worker manually, you can call
beygir.trigger('worker_queue')If you need to terminate a queue
beygir.end('worker_queue')Finally to shutdown beygir, call end method without arguments.
beygir.end()Worker file should export a function to be run in child process with signature below
module.exports = function worker(input, channel, callback) {
/*
*
*/
callback();
}input argument contains the message received from Redis pubsub
channel argument contains the channel name that message is received from
callback is the function provided with start method