javascript - Force protractor's onPrepare to wait for async http request

Question

My protractor conf.js,onPrepare function needs to make a http request that looks like,

onPrepare: function(done) {
    request.get('http://pepper/sysid')
      .end(function(err, resp){
        if(err || !resp.ok){
          log("there is an error " + err.message)
          done()
        }else{
          global.sysid = resp.sysid
          done()
         }
      })

It throws error as,done is not a function

Is there any other way, that i can force the callback inside onPrepare to be invoked before my tests start execution?

Answer 1

onPrepare() can optionally return a promise that protractor would resolve before starting to execute the tests:

onPrepare can optionally return a promise, which Protractor will wait for before continuing execution. This can be used if the preparation involves any asynchronous calls, e.g. interacting with the browser. Otherwise Protractor cannot guarantee order of execution and may start the tests before preparation finishes.

Make a protractor promise and return it from onPrepare():

onPrepare: function() {
    var defer = protractor.promise.defer();

    request.get('http://pepper/sysid').end(function(err, resp) {
        if (err || !resp.ok) {
            log("there is an error " + err.message);
            defer.reject(resp);
        } else {
            global.sysid = resp.sysid;
            defer.fulfill(resp);
        }
    });

    return defer.promise;
},