google qpx query in Google script - google-apps-script

Question

i'm tryng to request a (simple) flight-query trough google flight service via Apps Script
this is my code
function myFunction() {
var api_key = "XXXXXXXXXXXXXXX";
var url2= "https://www.googleapis.com/qpxExpress/v1/trips/search?key=" + api_key;
var param2 ={
"method" : "POST",
"contentType":"application/json",
"headers" : {"Content-Type": "application/json"
},
"request": {"passengers": {"adultCount": 1},
"slice": [{"origin": "BOS","destination": "LAX","date": "2015-03-01"}]
},
muteHttpExceptions : true
};
try {
var response = UrlFetchApp.fetch(url2,param2);
Logger.log(response)
} catch (e) {
Logger.log(e)
}
}
this request send me error code
"error": {"errors": [{
"domain": "global",
"reason": "badRequest",
"message": "Invalid inputs: received empty request."
}
],
"code": 400,
"message": "Invalid inputs: received empty request."
}
The qpx Api is loaded in my developer console....anyone has any idea?
thanks in advance

Answer 1

Two things, the body of the request must be specified with the "payload" property, not "request", and you must actually convert your Javascript Object to a JSON string before posting it. (You also don't need the "headers" property, "contentType" will suffice, but I don't think it hurts anything)
var param2 ={
"method" : "post",
"contentType":"application/json",
"payload": JSON.stringify({"passengers": {"adultCount": 1},
"slice": [{"origin": "BOS",
"destination": "LAX",
"date": "2015-03-01"
}]
}
),
muteHttpExceptions : true
};
It's all documented here: https://developers.google.com/apps-script/reference/url-fetch/url-fetch-app#fetch(String,Object)
However, the need to JSON.stringify() usually throws people off, if you pass a Javascript Object directly in the payload it is posted as form-encoded key/value pairs.

Answer 2

thanks very much...you put me in the right direction!
this is the right syntax:
var param2 ={
"method" : "post",
"contentType":"application/json",
"payload": JSON.stringify
(
{"request":
{"passengers": {"adultCount": 1},
"slice": [{"origin": "BOS",
"destination": "LAX",
"date": "2015-03-01"
}]
}
}
),
muteHttpExceptions : true
};