Post JSON data to an API via PHP - php

Question

I need to integrate JSON into PHP, more specifically I need to post some information from a php page on our site to initiate an API request which will then send me information back. The information I am sending revolves around login information and I am struggling to work out how I can send this information.
This is the information I need to post:
POST /user/?action=login HTTP/1.1
Host: api.interlinkexpress.com
Content-Type: application/json
Accept: application/json
Authorization: Basic RFNNSVRIOk1ZUEFTU1dE
GEOClient: account/123456
Content-Length: 0
Reading around the subject I have seen that php cURL may be useful however the example I have doesn't contain all the information I need to pass over. Also I am unsure on whether I need to pass it via a button as well:
$data = array("username" => "TESTAPI", "password" => "APITEST");
$data_string = json_encode($data);
$ch = curl_init('http://api.interlinkexpress.com');
curl_setopt($ch, CURLOPT_CUSTOMREQUEST, "POST");
curl_setopt($ch, CURLOPT_POSTFIELDS, $data_string);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_HTTPHEADER, array(
'Content-Type: application/json',
'Content-Length: ' . strlen($data_string))
);
$result = curl_exec($ch);
Any help on this matter would be appreciated. I am new to JSON having only learnt about it fleetingly.
edit: I suppose the main thing I'm asking is how do I pass this information to the API in PHP?
POST /user/?action=login HTTP/1.1
Host: api.interlinkexpress.com
Content-Type: application/json
Accept: application/json
Authorization: Basic RFNNSVRIOk1ZUEFTU1dE (this is the login credentials)
GEOClient: account/123456
Content-Length: 0

Answer 1

If you want something more powerful you can use Guzzle that integrates cURL in a really better way.
I don't get exactly what do you mean with passing it via a button. Are you talking just about PHP or also HTML/Javasript?
If you want a button you could proceed with a button that performs a XMLHttpRequest through Javascript, calling the API (that should return an application/json Content-Type), and then process this result via Javascript.
Or you can use cURL to call the API, get the result, json_decode it and do what you want with that.
You should explain better what you want to accomplish.
[EDIT]
Ok, after the clarifications I can tell you that you have to divide the parameters for the API from the settings for the HTTP call to the API (as you already did ^^ ).
So the parameters that will make the API to perform something are
action = login
while all the others are all setting for the HTTP client (cURL or Guzzle) that will perform the calling to the API's url
method = POST
Host = api.interlinkexpress.com
path = /user/
Accept = application/json
Content-Type = application/json
Authorization = Basic
GEOClient = account/123456 (is this a specific header needed from you API?)
Content-Length = 0
So, this is not complete nor tested but should give you a path to follow for adding
$data = array("action" => "login");
$data_string = json_encode($data);
$ch = curl_init(sprintf('%s/%s', 'http://api.interlinkexpress.com', 'user/');
curl_setopt($ch, CURLOPT_CUSTOMREQUEST, "POST");
curl_setopt($ch, CURLOPT_POSTFIELDS, $data_string);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_HTTPHEADER, array(
'Content-Type: application/json',
'Content-Length: ' . strlen($data_string)),
'GEOClient: account/123456',
);
// I would suggest you to add the timeout
curl_setopt($ch, CURLOPT_TIMEOUT, 30);
curl_setopt($ch, CURLOPT_HTTPAUTH, CURLAUTH_ANY); // or set it to CURLAUTH_BASIC
curl_setopt($ch, CURLOPT_USERPWD, sprintf('%s:%s', $data['username'],$data['password']));
$status_code = curl_getinfo($ch, CURLINFO_HTTP_CODE); //get status code
$result = curl_exec($ch);
I honestly don't get/know where you should send JSON encoded data.
This way you are sending the 'action' as JSON data, but I guess that this is wrong.
Maybe you want to pass the $data_string as the value of a specific field? (like in the example stated from PHP Develoer?)
Work on that, and understand exactly what data you have to pass as JSON and what NOT instead.
I hope to have helped you and gave good suggestions.

Answer 2

Your $data_string is not in format like (field=value).
Nothing to do just pass array into POST.
curl_setopt($ch, CURLOPT_POSTFIELDS, array('Data'=>$data_string));