includes/libs/virtualrest/VirtualRESTService.php

   1 <?php
   2 /**
   3  * Virtual HTTP service client
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  */
  22
  23 /**
  24  * Virtual HTTP service instance that can be mounted on to a VirtualRESTService
  25  *
  26  * Sub-classes manage the logic of either:
  27  *   - a) Munging virtual HTTP request arrays to have qualified URLs and auth headers
  28  *   - b) Emulating the execution of virtual HTTP requests (e.g. brokering)
  29  *
  30  * Authentication information can be cached in instances of the class for performance.
  31  * Such information should also be cached locally on the server and auth requests should
  32  * have reasonable timeouts.
  33  *
  34  * @since 1.23
  35  */
  36 abstract class VirtualRESTService {
  37         /** @var array Key/value map */
  38         protected $params = array();
  39
  40         /**
  41          * @param array $params Key/value map
  42          */
  43         public function __construct( array $params ) {
  44                 $this->params = $params;
  45         }
  46
  47         /**
  48          * Prepare virtual HTTP(S) requests (for this service) for execution
  49          *
  50          * This method should mangle any of the $reqs entry fields as needed:
  51          *   - url      : munge the URL to have an absolute URL with a protocol
  52          *                and encode path components as needed by the backend [required]
  53          *   - query    : include any authentication signatures/parameters [as needed]
  54          *   - headers  : include any authentication tokens/headers [as needed]
  55          *
  56          * The incoming URL parameter will be relative to the service mount point.
  57          *
  58          * This method can also remove some of the requests as well as add new ones
  59          * (using $idGenerator to set each of the entries' array keys). For any existing
  60          * or added request, the 'response' array can be filled in, which will prevent the
  61          * client from executing it. If an original request is removed, at some point it
  62          * must be added back (with the same key) in onRequests() or onResponses();
  63          * it's reponse may be filled in as with other requests.
  64          *
  65          * @param array $reqs Map of Virtual HTTP request arrays
  66          * @param Closure $idGeneratorFunc Method to generate unique keys for new requests
  67          * @return array Modified HTTP request array map
  68          */
  69         public function onRequests( array $reqs, Closure $idGeneratorFunc ) {
  70                 $result = array();
  71                 foreach ( $reqs as $key => $req ) {
  72                         // The default encoding treats the URL as a REST style path that uses
  73                         // forward slash as a hierarchical delimiter (and never otherwise).
  74                         // Subclasses can override this, and should be documented in any case.
  75                         $parts = array_map( 'rawurlencode', explode( '/', $req['url'] ) );
  76                         $req['url'] = $this->params['baseUrl'] . '/' . implode( '/', $parts );
  77                         $result[$key] = $req;
  78                 }
  79                 return $result;
  80         }
  81
  82         /**
  83          * Mangle or replace virtual HTTP(S) requests which have been responded to
  84          *
  85          * This method may mangle any of the $reqs entry 'response' fields as needed:
  86          *   - code    : perform any code normalization [as needed]
  87          *   - reason  : perform any reason normalization [as needed]
  88          *   - headers : perform any header normalization [as needed]
  89          *
  90          * This method can also remove some of the requests as well as add new ones
  91          * (using $idGenerator to set each of the entries' array keys). For any existing
  92          * or added request, the 'response' array can be filled in, which will prevent the
  93          * client from executing it. If an original request is removed, at some point it
  94          * must be added back (with the same key) in onRequests() or onResponses();
  95          * it's reponse may be filled in as with other requests. All requests added to $reqs
  96          * will be passed through onRequests() to handle any munging required as normal.
  97          *
  98          * The incoming URL parameter will be relative to the service mount point.
  99          *
 100          * @param array $reqs Map of Virtual HTTP request arrays with 'response' set
 101          * @param Closure $idGeneratorFunc Method to generate unique keys for new requests
 102          * @return array Modified HTTP request array map
 103          */
 104         public function onResponses( array $reqs, Closure $idGeneratorFunc ) {
 105                 return $reqs;
 106         }
 107 }