API: expect JWT in the Authorization header

Relates to https://github.com/shaarli/Shaarli/pull/731

Added:
- require the presence of the 'Authorization' header

Changed:
- use the HTTP Bearer Token authorization schema

See:
- https://jwt.io/introduction/#how-do-json-web-tokens-work-
- https://tools.ietf.org/html/rfc6750
- http://security.stackexchange.com/q/108662

Signed-off-by: VirtualTam <virtualtam@flibidi.net>

tests/api/ApiMiddlewareTest.php

@@ -143,7 +143,7 @@ class ApiMiddlewareTest extends \PHPUnit_Framework_TestCase
         $env = Environment::mock([
             'REQUEST_METHOD' => 'GET',
             'REQUEST_URI' => '/echo',
-            'HTTP_JWT'=> 'jwt',
+            'HTTP_AUTHORIZATION'=> 'Bearer jwt',
         ]);
         $request = Request::createFromEnvironment($env);
         $response = new Response();
@@ -157,7 +157,30 @@ class ApiMiddlewareTest extends \PHPUnit_Framework_TestCase
     }
 
     /**
-     * Invoke the middleware without an invalid JWT token (debug):
+     * Invoke the middleware with an invalid JWT token header
+     */
+    public function testInvalidJwtAuthHeaderDebug()
+    {
+        $this->conf->set('dev.debug', true);
+        $mw = new ApiMiddleware($this->container);
+        $env = Environment::mock([
+            'REQUEST_METHOD' => 'GET',
+            'REQUEST_URI' => '/echo',
+            'HTTP_AUTHORIZATION'=> 'PolarBearer jwt',
+        ]);
+        $request = Request::createFromEnvironment($env);
+        $response = new Response();
+        /** @var Response $response */
+        $response = $mw($request, $response, null);
+
+        $this->assertEquals(401, $response->getStatusCode());
+        $body = json_decode((string) $response->getBody());
+        $this->assertEquals('Not authorized: Invalid JWT header', $body->message);
+        $this->assertContains('ApiAuthorizationException', $body->stacktrace);
+    }
+
+    /**
+     * Invoke the middleware with an invalid JWT token (debug):
      * should return a 401 error Unauthorized - with a specific message and a stacktrace.
      *
      * Note: specific JWT errors tests are handled in ApiUtilsTest.
@@ -169,7 +192,7 @@ class ApiMiddlewareTest extends \PHPUnit_Framework_TestCase
         $env = Environment::mock([
             'REQUEST_METHOD' => 'GET',
             'REQUEST_URI' => '/echo',
-            'HTTP_JWT'=> 'bad jwt',
+            'HTTP_AUTHORIZATION'=> 'Bearer jwt',
         ]);
         $request = Request::createFromEnvironment($env);
         $response = new Response();