API * Common field output function to simplify result generation
[lhc/web/wiklou.git] / includes / api / ApiBase.php
1 <?php
2
3
4 /*
5 * Created on Sep 5, 2006
6 *
7 * API for MediaWiki 1.8+
8 *
9 * Copyright (C) 2006 Yuri Astrakhan <FirstnameLastname@gmail.com>
10 *
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License, or
14 * (at your option) any later version.
15 *
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU General Public License for more details.
20 *
21 * You should have received a copy of the GNU General Public License along
22 * with this program; if not, write to the Free Software Foundation, Inc.,
23 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
24 * http://www.gnu.org/copyleft/gpl.html
25 */
26
27 abstract class ApiBase {
28
29 // These constants allow modules to specify exactly how to treat incomming parameters.
30
31 const PARAM_DFLT = 0;
32 const PARAM_ISMULTI = 1;
33 const PARAM_TYPE = 2;
34 const PARAM_MAX1 = 3;
35 const PARAM_MAX2 = 4;
36 const PARAM_MIN = 5;
37
38 const LIMIT_BIG1 = 500; // Fast query, user's limit
39 const LIMIT_BIG2 = 5000; // Fast query, bot's limit
40 const LIMIT_SML1 = 50; // Slow query, user's limit
41 const LIMIT_SML2 = 500; // Slow query, bot's limit
42
43 private $mMainModule, $mModuleName, $mParamPrefix;
44
45 /**
46 * Constructor
47 */
48 public function __construct($mainModule, $moduleName, $paramPrefix = '') {
49 $this->mMainModule = $mainModule;
50 $this->mModuleName = $moduleName;
51 $this->mParamPrefix = $paramPrefix;
52 }
53
54 /**
55 * Executes this module
56 */
57 public abstract function execute();
58
59 /**
60 * Get the name of the module being executed by this instance
61 */
62 public function getModuleName() {
63 return $this->mModuleName;
64 }
65
66 /**
67 * Get the name of the module as shown in the profiler log
68 */
69 public function getModuleProfileName($db = false) {
70 if ($db)
71 return 'API:' . $this->mModuleName . '-DB';
72 else
73 return 'API:' . $this->mModuleName;
74 }
75
76 /**
77 * Get main module
78 */
79 public function getMain() {
80 return $this->mMainModule;
81 }
82
83 /**
84 * If this module's $this is the same as $this->mMainModule, its the root, otherwise no
85 */
86 public function isMain() {
87 return $this === $this->mMainModule;
88 }
89
90 /**
91 * Get result object
92 */
93 public function getResult() {
94 // Main module has getResult() method overriden
95 // Safety - avoid infinite loop:
96 if ($this->isMain())
97 ApiBase :: dieDebug(__METHOD__, 'base method was called on main module. ');
98 return $this->getMain()->getResult();
99 }
100
101 /**
102 * Get the result data array
103 */
104 public function & getResultData() {
105 return $this->getResult()->getData();
106 }
107
108 /**
109 * If the module may only be used with a certain format module,
110 * it should override this method to return an instance of that formatter.
111 * A value of null means the default format will be used.
112 */
113 public function getCustomPrinter() {
114 return null;
115 }
116
117 /**
118 * Generates help message for this module, or false if there is no description
119 */
120 public function makeHelpMsg() {
121
122 static $lnPrfx = "\n ";
123
124 $msg = $this->getDescription();
125
126 if ($msg !== false) {
127
128 if (!is_array($msg))
129 $msg = array (
130 $msg
131 );
132 $msg = $lnPrfx . implode($lnPrfx, $msg) . "\n";
133
134 // Parameters
135 $paramsMsg = $this->makeHelpMsgParameters();
136 if ($paramsMsg !== false) {
137 $msg .= "Parameters:\n$paramsMsg";
138 }
139
140 // Examples
141 $examples = $this->getExamples();
142 if ($examples !== false) {
143 if (!is_array($examples))
144 $examples = array (
145 $examples
146 );
147 $msg .= 'Example' . (count($examples) > 1 ? 's' : '') . ":\n ";
148 $msg .= implode($lnPrfx, $examples) . "\n";
149 }
150
151 if ($this->getMain()->getShowVersions()) {
152 $versions = $this->getVersion();
153 if (is_array($versions))
154 $versions = implode("\n ", $versions);
155 $msg .= "Version:\n $versions\n";
156 }
157 }
158
159 return $msg;
160 }
161
162 public function makeHelpMsgParameters() {
163 $params = $this->getAllowedParams();
164 if ($params !== false) {
165
166 $paramsDescription = $this->getParamDescription();
167 $msg = '';
168 $paramPrefix = "\n" . str_repeat(' ', 19);
169 foreach ($params as $paramName => $paramSettings) {
170 $desc = isset ($paramsDescription[$paramName]) ? $paramsDescription[$paramName] : '';
171 if (is_array($desc))
172 $desc = implode($paramPrefix, $desc);
173 if (isset ($paramSettings[self :: PARAM_TYPE])) {
174 $type = $paramSettings[self :: PARAM_TYPE];
175 if (is_array($type)) {
176 $desc .= $paramPrefix . 'Allowed values: ' . implode(', ', $type);
177 }
178 }
179
180 $default = is_array($paramSettings) ? (isset ($paramSettings[self :: PARAM_DFLT]) ? $paramSettings[self :: PARAM_DFLT] : null) : $paramSettings;
181 if (!is_null($default) && $default !== false)
182 $desc .= $paramPrefix . "Default: $default";
183
184 $msg .= sprintf(" %-14s - %s\n", $this->encodeParamName($paramName), $desc);
185 }
186 return $msg;
187
188 } else
189 return false;
190 }
191
192 /**
193 * Returns the description string for this module
194 */
195 protected function getDescription() {
196 return false;
197 }
198
199 /**
200 * Returns usage examples for this module. Return null if no examples are available.
201 */
202 protected function getExamples() {
203 return false;
204 }
205
206 /**
207 * Returns an array of allowed parameters (keys) => default value for that parameter
208 */
209 protected function getAllowedParams() {
210 return false;
211 }
212
213 /**
214 * Returns the description string for the given parameter.
215 */
216 protected function getParamDescription() {
217 return false;
218 }
219
220 /**
221 * This method mangles parameter name based on the prefix supplied to the constructor.
222 * Override this method to change parameter name during runtime
223 */
224 public function encodeParamName($paramName) {
225 return $this->mParamPrefix . $paramName;
226 }
227
228 /**
229 * Using getAllowedParams(), makes an array of the values provided by the user,
230 * with key being the name of the variable, and value - validated value from user or default.
231 * This method can be used to generate local variables using extract().
232 */
233 public function extractRequestParams() {
234 $params = $this->getAllowedParams();
235 $results = array ();
236
237 foreach ($params as $paramName => $paramSettings)
238 $results[$paramName] = $this->getParameterFromSettings($paramName, $paramSettings);
239
240 return $results;
241 }
242
243 /**
244 * Get a value for the given parameter
245 */
246 protected function getParameter($paramName) {
247 $params = $this->getAllowedParams();
248 $paramSettings = $params[$paramName];
249 return $this->getParameterFromSettings($paramName, $paramSettings);
250 }
251
252 /**
253 * Using the settings determine the value for the given parameter
254 * @param $paramName String: parameter name
255 * @param $paramSettings Mixed: default value or an array of settings using PARAM_* constants.
256 */
257 protected function getParameterFromSettings($paramName, $paramSettings) {
258
259 // Some classes may decide to change parameter names
260 $paramName = $this->encodeParamName($paramName);
261
262 if (!is_array($paramSettings)) {
263 $default = $paramSettings;
264 $multi = false;
265 $type = gettype($paramSettings);
266 } else {
267 $default = isset ($paramSettings[self :: PARAM_DFLT]) ? $paramSettings[self :: PARAM_DFLT] : null;
268 $multi = isset ($paramSettings[self :: PARAM_ISMULTI]) ? $paramSettings[self :: PARAM_ISMULTI] : false;
269 $type = isset ($paramSettings[self :: PARAM_TYPE]) ? $paramSettings[self :: PARAM_TYPE] : null;
270
271 // When type is not given, and no choices, the type is the same as $default
272 if (!isset ($type)) {
273 if (isset ($default))
274 $type = gettype($default);
275 else
276 $type = 'NULL'; // allow everything
277 }
278 }
279
280 if ($type == 'boolean') {
281 if (isset ($default) && $default !== false) {
282 // Having a default value of anything other than 'false' is pointless
283 ApiBase :: dieDebug(__METHOD__, "Boolean param $paramName's default is set to '$default'");
284 }
285
286 $value = $this->getMain()->getRequest()->getCheck($paramName);
287 } else {
288 $value = $this->getMain()->getRequest()->getVal($paramName, $default);
289 }
290
291 if (isset ($value) && ($multi || is_array($type)))
292 $value = $this->parseMultiValue($paramName, $value, $multi, is_array($type) ? $type : null);
293
294 // More validation only when choices were not given
295 // choices were validated in parseMultiValue()
296 if (isset ($value)) {
297 if (!is_array($type)) {
298 switch ($type) {
299 case 'NULL' : // nothing to do
300 break;
301 case 'string' : // nothing to do
302 break;
303 case 'integer' : // Force everything using intval()
304 $value = is_array($value) ? array_map('intval', $value) : intval($value);
305 break;
306 case 'limit' :
307 if (!isset ($paramSettings[self :: PARAM_MAX1]) || !isset ($paramSettings[self :: PARAM_MAX2]))
308 ApiBase :: dieDebug(__METHOD__, "MAX1 or MAX2 are not defined for the limit $paramName");
309 if ($multi)
310 ApiBase :: dieDebug(__METHOD__, "Multi-values not supported for $paramName");
311 $min = isset ($paramSettings[self :: PARAM_MIN]) ? $paramSettings[self :: PARAM_MIN] : 0;
312 $value = intval($value);
313 $this->validateLimit($paramName, $value, $min, $paramSettings[self :: PARAM_MAX1], $paramSettings[self :: PARAM_MAX2]);
314 break;
315 case 'boolean' :
316 if ($multi)
317 ApiBase :: dieDebug(__METHOD__, "Multi-values not supported for $paramName");
318 break;
319 case 'timestamp' :
320 if ($multi)
321 ApiBase :: dieDebug(__METHOD__, "Multi-values not supported for $paramName");
322 $value = wfTimestamp(TS_UNIX, $value);
323 if ($value === 0)
324 $this->dieUsage("Invalid value '$value' for timestamp parameter $paramName", "badtimestamp_{$paramName}");
325 $value = wfTimestamp(TS_MW, $value);
326 break;
327 default :
328 ApiBase :: dieDebug(__METHOD__, "Param $paramName's type is unknown - $type");
329
330 }
331 }
332
333 // There should never be any duplicate values in a list
334 if (is_array($value))
335 $value = array_unique($value);
336 }
337
338 return $value;
339 }
340
341 /**
342 * Return an array of values that were given in a 'a|b|c' notation,
343 * after it optionally validates them against the list allowed values.
344 *
345 * @param valueName - The name of the parameter (for error reporting)
346 * @param value - The value being parsed
347 * @param allowMultiple - Can $value contain more than one value separated by '|'?
348 * @param allowedValues - An array of values to check against. If null, all values are accepted.
349 * @return (allowMultiple ? an_array_of_values : a_single_value)
350 */
351 protected function parseMultiValue($valueName, $value, $allowMultiple, $allowedValues) {
352 $valuesList = explode('|', $value);
353 if (!$allowMultiple && count($valuesList) != 1) {
354 $possibleValues = is_array($allowedValues) ? "of '" . implode("', '", $allowedValues) . "'" : '';
355 $this->dieUsage("Only one $possibleValues is allowed for parameter '$valueName'", "multival_$valueName");
356 }
357 if (is_array($allowedValues)) {
358 $unknownValues = array_diff($valuesList, $allowedValues);
359 if ($unknownValues) {
360 $this->dieUsage('Unrecognised value' . (count($unknownValues) > 1 ? "s" : "") . " for parameter '$valueName'", "unknown_$valueName");
361 }
362 }
363
364 return $allowMultiple ? $valuesList : $valuesList[0];
365 }
366
367 /**
368 * Validate the value against the minimum and user/bot maximum limits. Prints usage info on failure.
369 */
370 function validateLimit($varname, $value, $min, $max, $botMax) {
371 if ($value < $min) {
372 $this->dieUsage("$varname may not be less than $min (set to $value)", $varname);
373 }
374
375 if ($this->getMain()->isBot()) {
376 if ($value > $botMax) {
377 $this->dieUsage("$varname may not be over $botMax (set to $value) for bots", $varname);
378 }
379 }
380 elseif ($value > $max) {
381 $this->dieUsage("$varname may not be over $max (set to $value) for users", $varname);
382 }
383 }
384
385 /**
386 * Call main module's error handler
387 */
388 public function dieUsage($description, $errorCode, $httpRespCode = 0) {
389 throw new UsageException($description, $this->encodeParamName($errorCode), $httpRespCode);
390 }
391
392 /**
393 * Internal code errors should be reported with this method
394 */
395 protected static function dieDebug($method, $message) {
396 wfDebugDieBacktrace("Internal error in $method: $message");
397 }
398
399 /**
400 * Profiling: total module execution time
401 */
402 private $mTimeIn = 0, $mModuleTime = 0;
403
404 /**
405 * Start module profiling
406 */
407 public function profileIn() {
408 if ($this->mTimeIn !== 0)
409 ApiBase :: dieDebug(__METHOD__, 'called twice without calling profileOut()');
410 $this->mTimeIn = microtime(true);
411 wfProfileIn($this->getModuleProfileName());
412 }
413
414 /**
415 * End module profiling
416 */
417 public function profileOut() {
418 if ($this->mTimeIn === 0)
419 ApiBase :: dieDebug(__METHOD__, 'called without calling profileIn() first');
420 if ($this->mDBTimeIn !== 0)
421 ApiBase :: dieDebug(__METHOD__, 'must be called after database profiling is done with profileDBOut()');
422
423 $this->mModuleTime += microtime(true) - $this->mTimeIn;
424 $this->mTimeIn = 0;
425 wfProfileOut($this->getModuleProfileName());
426 }
427
428 /**
429 * When modules crash, sometimes it is needed to do a profileOut() regardless
430 * of the profiling state the module was in. This method does such cleanup.
431 */
432 public function safeProfileOut() {
433 if ($this->mTimeIn !== 0) {
434 if ($this->mDBTimeIn !== 0)
435 $this->profileDBOut();
436 $this->profileOut();
437 }
438 }
439
440 /**
441 * Total time the module was executed
442 */
443 public function getProfileTime() {
444 if ($this->mTimeIn !== 0)
445 ApiBase :: dieDebug(__METHOD__, 'called without calling profileOut() first');
446 return $this->mModuleTime;
447 }
448
449 /**
450 * Profiling: database execution time
451 */
452 private $mDBTimeIn = 0, $mDBTime = 0;
453
454 /**
455 * Start module profiling
456 */
457 public function profileDBIn() {
458 if ($this->mTimeIn === 0)
459 ApiBase :: dieDebug(__METHOD__, 'must be called while profiling the entire module with profileIn()');
460 if ($this->mDBTimeIn !== 0)
461 ApiBase :: dieDebug(__METHOD__, 'called twice without calling profileDBOut()');
462 $this->mDBTimeIn = microtime(true);
463 wfProfileIn($this->getModuleProfileName(true));
464 }
465
466 /**
467 * End database profiling
468 */
469 public function profileDBOut() {
470 if ($this->mTimeIn === 0)
471 ApiBase :: dieDebug(__METHOD__, 'must be called while profiling the entire module with profileIn()');
472 if ($this->mDBTimeIn === 0)
473 ApiBase :: dieDebug(__METHOD__, 'called without calling profileDBIn() first');
474
475 $time = microtime(true) - $this->mDBTimeIn;
476 $this->mDBTimeIn = 0;
477
478 $this->mDBTime += $time;
479 $this->getMain()->mDBTime += $time;
480 wfProfileOut($this->getModuleProfileName(true));
481 }
482
483 /**
484 * Total time the module used the database
485 */
486 public function getProfileDBTime() {
487 if ($this->mDBTimeIn !== 0)
488 ApiBase :: dieDebug(__METHOD__, 'called without calling profileDBOut() first');
489 return $this->mDBTime;
490 }
491
492 public abstract function getVersion();
493
494 public static function getBaseVersion() {
495 return __CLASS__ . ': $Id$';
496 }
497 }
498 ?>