promise-series-chain-example.js

// Promise series example
function task(name) {

    return new Promise(function(resolve, reject) {
       setTimeout(function() {
        console.log(name, new Date());
        if (name === 'fail') {
            reject(name);
        } else {
            resolve(name);         
        }
        
       }, 2000);
       
    });

}

task('t1')
    .then(function(resp) {
        return task('t2');
    })
    .then(function(resp) {
        return task('fail'); // force fail
    })
    .then(function(resp) {
        return task('t3');
    })        
    .then(function(resp) {
        console.log(resp, 'done');
    })
    .catch(function(err) {
        console.error(err);
    });