CartoDB-SQL-API/batch/job_queue.js
Daniel García Aubert 8f35e1d1af Fix typo
2017-04-03 11:38:20 +02:00

67 lines
1.9 KiB
JavaScript

'use strict';
var debug = require('./util/debug')('queue');
function JobQueue(metadataBackend, jobPublisher) {
this.metadataBackend = metadataBackend;
this.jobPublisher = jobPublisher;
}
module.exports = JobQueue;
var QUEUE = {
DB: 5,
PREFIX: 'batch:queue:',
INDEX: 'batch:indexes:queue'
};
module.exports.QUEUE = QUEUE;
JobQueue.prototype.enqueue = function (user, jobId, callback) {
debug('JobQueue.enqueue user=%s, jobId=%s', user, jobId);
this.metadataBackend.redisMultiCmd(QUEUE.DB, [
[ 'LPUSH', QUEUE.PREFIX + user, jobId ],
[ 'SADD', QUEUE.INDEX, user ]
], function (err) {
if (err) {
return callback(err);
}
this.jobPublisher.publish(user);
callback();
}.bind(this));
};
JobQueue.prototype.size = function (user, callback) {
this.metadataBackend.redisCmd(QUEUE.DB, 'LLEN', [ QUEUE.PREFIX + user ], callback);
};
JobQueue.prototype.dequeue = function (user, callback) {
var dequeueScript = [
'local job_id = redis.call("RPOP", KEYS[1])',
'if redis.call("LLEN", KEYS[1]) == 0 then',
' redis.call("SREM", KEYS[2], ARGV[1])',
'end',
'return job_id'
].join('\n');
var redisParams = [
dequeueScript, //lua source code
2, // Two "keys" to pass
QUEUE.PREFIX + user, //KEYS[1], the key of the queue
QUEUE.INDEX, //KEYS[2], the key of the index
user // ARGV[1] - value of the element to remove from the index
];
this.metadataBackend.redisCmd(QUEUE.DB, 'EVAL', redisParams, function (err, jobId) {
debug('JobQueue.dequeued user=%s, jobId=%s', user, jobId);
return callback(err, jobId);
});
};
JobQueue.prototype.enqueueFirst = function (user, jobId, callback) {
debug('JobQueue.enqueueFirst user=%s, jobId=%s', user, jobId);
this.metadataBackend.redisCmd(QUEUE.DB, 'RPUSH', [ QUEUE.PREFIX + user, jobId ], callback);
};