Query QPX Express from R - r

Question

I'm trying to query QPX Exprss (Google) from R (httr) but for whatever reason I'm getting 0 results. This is my query:
x <- list(
request = list(
slice = list(c(origin = "BOS", destination = "LAX", date = "2014-07-29")),
passengers = c(adultCount = 1, infantInLapCount = 0, infantInSeatCount = 0,
childCount = 0, seniorCount = 0),
solutions = 10,
refundable = "false")
)
And this is the command:
POST("https://www.googleapis.com/qpxExpress/v1/trips/search?key=MY_KEY",
body = toJSON(x), add_headers("Content-Type" = "application/json"), verbose(),
add_headers(Expect = ""))
Finally, the response from Google:
* About to connect() to www.googleapis.com port 443 (#0)
* Trying 173.194.66.95... * connected
* Connected to www.googleapis.com (173.194.66.95) port 443 (#0)
* successfully set certificate verify locations:
* CAfile: C:/Users/XXXX/Documents/R/win-library/3.1/httr/cacert.pem
CApath: none
* SSL re-using session ID
* SSL connection using ECDHE-RSA-RC4-SHA
* Server certificate:
* subject: C=US; ST=California; L=Mountain View; O=Google Inc; CN=*.googleapis.com
* start date: 2014-07-02 13:35:47 GMT
* expire date: 2014-09-30 00:00:00 GMT
* subjectAltName: www.googleapis.com matched
* issuer: C=US; O=Google Inc; CN=Google Internet Authority G2
* SSL certificate verify ok.
> POST /qpxExpress/v1/trips/search?key=MY_KEY HTTP/1.1
Host: www.googleapis.com
Accept: */*
Accept-Encoding: gzip
user-agent: curl/7.19.6 Rcurl/1.95.4.1 httr/0.3
Content-Type: application/json
Content-Length: 220
< HTTP/1.1 200 OK
< Cache-Control: no-cache, no-store, max-age=0, must-revalidate
< Pragma: no-cache
< Expires: Fri, 01 Jan 1990 00:00:00 GMT
< Date: Mon, 21 Jul 2014 10:39:46 GMT
< ETag: "FHaaT3rgbj6tTc1zJmPkVQ6bD-8/wa9h__cUdEwRE2bp0yW5NTA6fec"
< Content-Type: application/json; charset=UTF-8
< Content-Encoding: gzip
< X-Content-Type-Options: nosniff
< X-Frame-Options: SAMEORIGIN
< X-XSS-Protection: 1; mode=block
< Server: GSE
< Alternate-Protocol: 443:quic
< Transfer-Encoding: chunked
<
* Connection #0 to host www.googleapis.com left intact
Response [https://www.googleapis.com/qpxExpress/v1/trips/search?key=MY_KEY]
Status: 200
Content-type: application/json; charset=UTF-8
{
"kind": "qpxExpress#tripsSearch",
"trips": {
"kind": "qpxexpress#tripOptions",
"requestId": "UTlu4NDcLz3Ypcicp0KKI3",
"data": {
"kind": "qpxexpress#data",
"airport": [
{
"kind": "qpxexpress#airportData", ...
Has anybody had any luck with this?
Thanks a bunch!
Carlos

Answer 1

In case anybody is interested. These are the answers from Duncan and Hadley:
The postForm command from Windows would be as follows:
library(RCurl)
library(RJSONIO)
x <- list(
request = list(
passengers = list(
adultCount = 1
),
slice = list(
list(
origin = "BOS",
destination = "LAX",
date = "2014-07-29"
)
),
refundable = "false",
solutions = 10
)
)
postForm("https://www.googleapis.com/qpxExpress/v1/trips/search?key=my_KEY",
.opts = list(postfields = toJSON(x),
cainfo = system.file("CurlSSL", "cacert.pem", package = "RCurl"),
httpheader = c('Content-Type' = 'application/json',
Accept = 'application/json'),
verbose = TRUE
))
You can omit
cainfo = system.file("CurlSSL", "cacert.pem", package = "RCurl")
if you are running on a Linux machine.
If you rather use httr, here it is the command:
library(httr)
url <- "https://www.googleapis.com/qpxExpress/v1/trips/search"
json <- jsonlite::toJSON(x, auto_unbox = TRUE)
POST(url, query = list(key = my_Key), body = json, content_type_json())
Cheers.
Carlos