Var_Dump (Error 400 - Bad Request) - php

Question

I am working on a little project for a programming course here on my university. It involves getting data from the google api (JSON) and providing some of that information to the user.
function compare($city, $start, $destination)
{
// merge city with start and destination
$city_start = $start . ', ' . $city;
$city_destination = $destination . ', ' . $city;
// reject symbols that start with ^
if (preg_match("/^\^/", $city) OR preg_match("/^\^/", $start) OR preg_match("/^\^/", $destination))
{
return false;
}
// reject symbols that contain commas
if (preg_match("/,/", $city) OR preg_match("/,/", $start) OR preg_match("/,/", $city))
{
return false;
}
// determine url
$url = "http://maps.googleapis.com/maps/api/directions/json?origin=$city_start&destination=$city_destination&sensor=false&mode=bicycling";
echo $url;
// open connection to google maps
$curl_session = curl_init($url);
curl_setopt($curl_session, CURLOPT_RETURNTRANSFER, true);
curl_setopt($curl_session, CURLOPT_HEADER, 0);
// get data from json output
$json = curl_exec($curl_session);
curl_close($curl_session);
var_dump($json);
}
The above code returns a 400 error at var_dump, where $city, $start and $destination are respectively starting adress, destination adress and the city where the addresses belong to. The url stored in $url works alright and returns JSON output when entered in a browser.
Can anyone tell me what I am doing wrong?
Cheers,
D.

Answer 1

You could try and urlencode the variables:
$city_start = urlencode($start . ', ' . $city);
$city_destination = urlencode($destination . ', ' . $city);