Question

I’m trying to use a web service REST API for which I need to add a parameter for authorization (with the appropriate key, of course) to get a XML result. I’m developing in PHP. How can I add a parameter to the request header in such a situation?

Edit: The way I’m doing the request right now is $xml = simplexml_load_file($query_string);

Answer 1

Are you using curl? (recommended)

I assume that you are using curl to do these requests towards the REST API, if you aren’t; use it.

When using curl you can add a custom header by calling curl_setopt with the appropriate parameters, such as in below.

 curl_setopt (
   $curl_handle, CURLOPT_HTTPHEADER,
   array ('Authentication-Key: foobar')
 ); // make curl send a HTTP header named 'Authentication-key'
    // with the value 'foobar'

Documentation:

• PHP: cURL – Manual
• PHP: curl_setopt – Manual

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Are you using file_get_contents or similar?

This method is not recommended, though it is functional.

Note: allow_url_fopen needs to be enabled for file_get_contents to be able to access resources over HTTP.

If you’d like to add a custom header to such request you’ll need to create yourself a valid stream context, as in the below snippet:

$context_options = array(
  'http' =>array (
    'method' => 'GET',
    'header' => 'Authentication-Key'
  )
);

$context  = stream_context_create ($context_options);

$response = file_get_contents (
  'http://www.stackoverflow.com', false, $context_options
);

Documentation:

• PHP: file_get_contents – Manual
• PHP: stream_context_create – Manual
• PHP: Runtime Configuration, allow_url_fopen

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I’m using neither of the above solutions, what should I do?

[Post OP EDIT]

My recommendation is to fetch the data using curl and then pass it off to the parser in question when all the data is received. Separate data fetching from the processing of the returned data.

[/Post OP EDIT]

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