feature symfony#4128 Finished symfony#3759 (WouterJ)

This PR was merged into the 2.4 branch.

Discussion
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Finished symfony#3759

Finished the great start by @BourotBenjamin in symfony#3759

Commits
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529675a Check for api_key in request
59e4bd4 Update api_key_authentication.rst - POST Method

Author: weaverryan

cookbook/security/api_key_authentication.rst

@@ -45,13 +45,19 @@ value and then a User object is created::
 
         public function createToken(Request $request, $providerKey)
         {
-            if (!$request->query->has('apikey')) {
+            // look for an apikey query parameter
+            $apiKey = $request->query->get('apikey');
+
+            // or if you want to use an "apikey" header, then do something like this:
+            // $apiKey = $request->headers->get('apikey');
+
+            if (!$apiKey) {
                 throw new BadCredentialsException('No API key found');
             }
 
             return new PreAuthenticatedToken(
                 'anon.',
-                $request->query->get('apikey'),
+                $apiKey,
                 $providerKey
             );
         }