How do I troubleshoot freebusy google calendar nodejs api?

Question

I am trying to get free-busy information from Google Calendar using the NodeJS API as listed here https://developers.google.com/google-apps/calendar/v3/reference/freebusy/query. The problem is that the only error response I get is 'invalid request'. When I run it with the Google's Try It tool, i am able to get response though. I know that I am getting an authorized client. What can I do to troubleshoot this further?

function getAvail(auth, dateTimeRange, calID) {
    var deferred = Q.defer(); // get a new deferral
    calendar.freebusy.query({
            auth: auth,
            items: [{id: calID}],
            timeMin: (dateTimeRange.start).toISOString(),
            timeMax: (dateTimeRange.end).toISOString(),
            }, function(err, response) {
                    console.log('Response from the Calendar service: ' + response);
                    if (err) {
                            console.log('There was an error contacting the Calendar service: ' + err);
                            deferred.reject(); // deferred reject here
                            return;
                    }   
                    var events = response[calID]['busy'];
                    if (events.length == 0) {
                            console.log('No upcoming events found.');
                    } else {
                            console.log('busy in here...');
                    }   
                    deferred.resolve(response); // deferred resolve here
            }); 
    return deferred.promise; // return a promise

}

Answer 1

Phew! I finally figured out what I was doing wrong. Here is the code that works with comments where I was making a mistake. I wish there was a better way to finding out this issue.

function getAvail(auth, dateTimeRange, calID) {
    console.log('auth:'+JSON.stringify(auth));
    console.log('date Time Range :'+(dateTimeRange.start).toISOString()+' --->'+(dateTimeRange.end).toISOString());
    console.log('calendar id to check freebusy:'+calID);
    var deferred = Q.defer(); // get a new deferral
    calendar.freebusy.query({
            auth: auth,
            headers: { "content-type" : "application/json" },
            resource:{items: [{"id" : calID}],   //needed to include resource instead of sending the params directly.

                      timeMin: (dateTimeRange.start).toISOString(),
                      timeMax: (dateTimeRange.end).toISOString()
                    }   
    }, function(err, response) {
                    console.log('Response from the Calendar service: ' + JSON.stringify(response));
                    if (err) {
                            console.log('There was an error contacting the Calendar service: ' + err);
                            deferred.reject(); // deferred reject here
                            return;
                    }   
                    var events = response.calendars[calID].busy;
                    if (events.length == 0) {
                            console.log('No upcoming events found.');
                    } else {
                            console.log('busy in here...');
                    }   
                    deferred.resolve(response); // deferred resolve here
            }); 
    return deferred.promise; // return a promise
}

It was a lot of meditation and staring at the documentation closely. Google's nodejs library is not particularly well-documented with examples yet (well, it is still alpha). But here is the function for freebusy:

this.freebusy = {

    /**
     * calendar.freebusy.query
     *
     * @desc Returns free/busy information for a set of calendars.
     *
     * @alias calendar.freebusy.query
     * @memberOf! calendar(v3)
     *
     * @param  {object} params - Parameters for request
     * @param  {object} params.resource - Request body data** <<<< -- this is what I was missing.
     * @param  {callback} callback - The callback that handles the response.
     * @return {object} Request object
     */
    query: function(params, callback) {
      var parameters = {
        options: {
          url: 'https://www.googleapis.com/calendar/v3/freeBusy',
          method: 'POST'
        },
        params: params,
        requiredParams: [],
        pathParams: [],
        context: self
      };

      return createAPIRequest(parameters, callback);
    }

};

There were some additional learns about creating closures inside loops which I learned on SO from here: JavaScript closure inside loops – simple practical example. Let me know if anyone else runs into the similar issues. I will be happy to share my code samples.