Retrieving response after posting data using PHP Curl - php

Question

I am trying to make an API call to Localbitcoins API using Curl, but I am having difficulty getting the response to return properly. I have looked at my Curl request and nothing looks out of place.
Here is the API call I am trying to get:
Base URL: https://localbitcoins.com/oauth2/access_token/
Required arguments: client_id, client_secret, username, password, grant_type=password
Optional arguments: None
If successful, JSON like so will be returned immediately:
{
"access_token": the access token,
"scope": "read",
"expires_in": seconds to expiry,
"refresh_token": a refresh token
}
and here is the function I have written to try and retrieve the access_token:
function authenticate($parameters) {
$url = 'https://localbitcoins.com/oauth2/access_token/';
$parameters['client_id'] = 'redacted';
$parameters['client_secret'] = 'redacted';
$data = http_build_query($parameters);
// Initialize the PHP curl agent
$ch = curl_init();
curl_setopt($ch, CURLOPT_USERAGENT, "curl");
curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_FAILONERROR, true);
curl_setopt($ch, CURLOPT_POST, true);
curl_setopt($ch, CURLOPT_POSTFIELDS, $data);
// curl_setopt($ch, CURLOPT_VERBOSE, true);
$result = curl_exec($ch);
if ($result === false)
throw new Exception ("curl Error: " . curl_error($ch));
$http_status = curl_getinfo($ch, CURLINFO_HTTP_CODE);
if ($http_status != 200)
throw new Exception("Request Failed. http status: " . $http_status);
curl_close($ch);
// Trim any whitespace from the front and end of the string and decode it
$result = json_decode(trim($result));
if (($error = get_json_error()) !== false) {
throw new Exception("json_decode failed: " . $error);
}
// Verify that we got a valid response
if (!isset($result->status))
{
throw new Exception("API response did not contain 'status'");
exit;
}
if ($result->status == 'error')
{
throw new Exception("API call failed: " . $result->message);
exit;
}
// The API call succeeded, return the requested data
return $result->data;
}
and calling the function:
authenticate(array(
'grant_type' => 'password',
'username' => 'redacted',
'password' => 'redacted'));
All this returns is FATAL ERROR and a 400 ERROR for BAD REQUEST. Any help would be greatly appreciated!

Answer 1

I don't think it's worth your time to develop for the current Localbitcoins API. It's very poorly documented with a lot of broken features. If you look at the Developer forum, it's not well maintained and its riddled with complaints:
https://localbitcoins.com/forums/#!/dev/developers-and-affiliates
I personally inquired on the status of the API with one of the Localbitcoin developers, and he told me that they are pushing out an updated API within the next two weeks.
As per your question specifically, it seems like the issue has existed since October 2013:
https://localbitcoins.com/forums/#!/dev/developers-and-affiliates#problems-with-grant-typepa
Doesn't look like anyone from the Localbitcoins team has resolved it either. I think you are better off holding off for their new API.
Cheers!

Answer 2

can you try this...
$result = curl_exec($ch);
echo nl2br($result);
curl_close($ch);