How to do parallel async multiple requests at once with Promises in Node

Question

Array and loops through but I want to be able to run all of them in parallel instead as I don\'t want to run one after another.

I basically want to store all endpoin

Answer 1

You can use Promise.map with .bind:

function getComponentStatuses(componentsToCheck) {
    return Promise.map(componentsToCheck, function() {
        var start = Date.now();
        return getAsync({
            url: component.endpoint,
            timeout: component.timeout
        })
        .bind({
             name: component.name,
             status: null,
             body: null,
             time: null
        })
        .spread(function(response, body){
            Logger.info('GET took ' + end + 'ms.');
            this.status = response.statusCode;
            this.body = body;
            return this;
        })
        .catch(function(e) { return this; })
        .finally(function() { this.time = Date.now() - start; })
    });
}

Note that your timing method is incorrect because the http agent might throttle requests.

Answer 2

Found the solution.

Use .settle

Answer 3

Bluebird supports multiple concurrent Promises.

See the reference at: https://github.com/petkaantonov/bluebird/blob/master/API.md#promisejoinpromisethenablevalue-promises-function-handler---promise

There are two ways to do it:

.all() - good for a dynamic number of promises

.join() - good for a fixed number of promises and as for Bluebird's documentation, it supplies a better performance than .all() method.

From bluebird's documentation:

 var Promise = require("bluebird");
 var join = Promise.join;

join(getPictures(), getComments(), getTweets(),
function(pictures, comments, tweets) {
console.log("in total: " + pictures.length + comments.length + tweets.length);
});

Answer 4

I use q Promise Maybe help

return q.all([function or value1, function or value 2, ......])
.spread(function (result1, result2, ....) {
   // do somethine
})

............