How to run Generator Functions in Parallel?

Question

Assuming I have a Koa web server with an endpoint like this:

const perform = require(...); // some generator function

exports.endpoint = function* () {

            


        

Answer 1

co turns the generator function to Promises, and executes them async. Promise.all waits for all of them to finish:

exports.getResults = function* () {

    var actions = [...];

    return yield Promise.all(actions.map(function(action) { 
        return co(function*() { 
            return yield perform(action); 
        } 
    }));
}