tests/phpunit/includes/libs/objectcache/WANObjectCacheTest.php

   1 <?php
   2
   3 use Wikimedia\TestingAccessWrapper;
   4
   5 class WANObjectCacheTest extends PHPUnit_Framework_TestCase  {
   6         /** @var WANObjectCache */
   7         private $cache;
   8         /**@var BagOStuff */
   9         private $internalCache;
  10
  11         protected function setUp() {
  12                 parent::setUp();
  13
  14                 $this->cache = new WANObjectCache( [
  15                         'cache' => new HashBagOStuff(),
  16                         'pool' => 'testcache-hash',
  17                         'relayer' => new EventRelayerNull( [] )
  18                 ] );
  19
  20                 $wanCache = TestingAccessWrapper::newFromObject( $this->cache );
  21                 /** @noinspection PhpUndefinedFieldInspection */
  22                 $this->internalCache = $wanCache->cache;
  23         }
  24
  25         /**
  26          * @dataProvider provideSetAndGet
  27          * @covers WANObjectCache::set()
  28          * @covers WANObjectCache::get()
  29          * @covers WANObjectCache::makeKey()
  30          * @param mixed $value
  31          * @param integer $ttl
  32          */
  33         public function testSetAndGet( $value, $ttl ) {
  34                 $curTTL = null;
  35                 $asOf = null;
  36                 $key = $this->cache->makeKey( 'x', wfRandomString() );
  37
  38                 $this->cache->get( $key, $curTTL, [], $asOf );
  39                 $this->assertNull( $curTTL, "Current TTL is null" );
  40                 $this->assertNull( $asOf, "Current as-of-time is infinite" );
  41
  42                 $t = microtime( true );
  43                 $this->cache->set( $key, $value, $ttl );
  44
  45                 $this->assertEquals( $value, $this->cache->get( $key, $curTTL, [], $asOf ) );
  46                 if ( is_infinite( $ttl ) || $ttl == 0 ) {
  47                         $this->assertTrue( is_infinite( $curTTL ), "Current TTL is infinite" );
  48                 } else {
  49                         $this->assertGreaterThan( 0, $curTTL, "Current TTL > 0" );
  50                         $this->assertLessThanOrEqual( $ttl, $curTTL, "Current TTL < nominal TTL" );
  51                 }
  52                 $this->assertGreaterThanOrEqual( $t - 1, $asOf, "As-of-time in range of set() time" );
  53                 $this->assertLessThanOrEqual( $t + 1, $asOf, "As-of-time in range of set() time" );
  54         }
  55
  56         public static function provideSetAndGet() {
  57                 return [
  58                         [ 14141, 3 ],
  59                         [ 3535.666, 3 ],
  60                         [ [], 3 ],
  61                         [ null, 3 ],
  62                         [ '0', 3 ],
  63                         [ (object)[ 'meow' ], 3 ],
  64                         [ INF, 3 ],
  65                         [ '', 3 ],
  66                         [ 'pizzacat', INF ],
  67                 ];
  68         }
  69
  70         /**
  71          * @covers WANObjectCache::get()
  72          * @covers WANObjectCache::makeGlobalKey()
  73          */
  74         public function testGetNotExists() {
  75                 $key = $this->cache->makeGlobalKey( 'y', wfRandomString(), 'p' );
  76                 $curTTL = null;
  77                 $value = $this->cache->get( $key, $curTTL );
  78
  79                 $this->assertFalse( $value, "Non-existing key has false value" );
  80                 $this->assertNull( $curTTL, "Non-existing key has null current TTL" );
  81         }
  82
  83         /**
  84          * @covers WANObjectCache::set()
  85          */
  86         public function testSetOver() {
  87                 $key = wfRandomString();
  88                 for ( $i = 0; $i < 3; ++$i ) {
  89                         $value = wfRandomString();
  90                         $this->cache->set( $key, $value, 3 );
  91
  92                         $this->assertEquals( $this->cache->get( $key ), $value );
  93                 }
  94         }
  95
  96         /**
  97          * @covers WANObjectCache::set()
  98          */
  99         public function testStaleSet() {
 100                 $key = wfRandomString();
 101                 $value = wfRandomString();
 102                 $this->cache->set( $key, $value, 3, [ 'since' => microtime( true ) - 30 ] );
 103
 104                 $this->assertFalse( $this->cache->get( $key ), "Stale set() value ignored" );
 105         }
 106
 107         public function testProcessCache() {
 108                 $hit = 0;
 109                 $callback = function () use ( &$hit ) {
 110                         ++$hit;
 111                         return 42;
 112                 };
 113                 $keys = [ wfRandomString(), wfRandomString(), wfRandomString() ];
 114                 $groups = [ 'thiscache:1', 'thatcache:1', 'somecache:1' ];
 115
 116                 foreach ( $keys as $i => $key ) {
 117                         $this->cache->getWithSetCallback(
 118                                 $key, 100, $callback, [ 'pcTTL' => 5, 'pcGroup' => $groups[$i] ] );
 119                 }
 120                 $this->assertEquals( 3, $hit );
 121
 122                 foreach ( $keys as $i => $key ) {
 123                         $this->cache->getWithSetCallback(
 124                                 $key, 100, $callback, [ 'pcTTL' => 5, 'pcGroup' => $groups[$i] ] );
 125                 }
 126                 $this->assertEquals( 3, $hit, "Values cached" );
 127
 128                 foreach ( $keys as $i => $key ) {
 129                         $this->cache->getWithSetCallback(
 130                                 "$key-2", 100, $callback, [ 'pcTTL' => 5, 'pcGroup' => $groups[$i] ] );
 131                 }
 132                 $this->assertEquals( 6, $hit );
 133
 134                 foreach ( $keys as $i => $key ) {
 135                         $this->cache->getWithSetCallback(
 136                                 "$key-2", 100, $callback, [ 'pcTTL' => 5, 'pcGroup' => $groups[$i] ] );
 137                 }
 138                 $this->assertEquals( 6, $hit, "New values cached" );
 139
 140                 foreach ( $keys as $i => $key ) {
 141                         $this->cache->delete( $key );
 142                         $this->cache->getWithSetCallback(
 143                                 $key, 100, $callback, [ 'pcTTL' => 5, 'pcGroup' => $groups[$i] ] );
 144                 }
 145                 $this->assertEquals( 9, $hit, "Values evicted" );
 146
 147                 $key = reset( $keys );
 148                 // Get into cache
 149                 $this->cache->getWithSetCallback( $key, 100, $callback, [ 'pcTTL' => 5 ] );
 150                 $this->cache->getWithSetCallback( $key, 100, $callback, [ 'pcTTL' => 5 ] );
 151                 $this->assertEquals( 10, $hit, "Value cached" );
 152                 $outerCallback = function () use ( &$callback, $key ) {
 153                         $v = $this->cache->getWithSetCallback( $key, 100, $callback, [ 'pcTTL' => 5 ] );
 154
 155                         return 43 + $v;
 156                 };
 157                 $this->cache->getWithSetCallback( $key, 100, $outerCallback );
 158                 $this->assertEquals( 11, $hit, "Nested callback value process cache skipped" );
 159         }
 160
 161         /**
 162          * @dataProvider getWithSetCallback_provider
 163          * @covers WANObjectCache::getWithSetCallback()
 164          * @covers WANObjectCache::doGetWithSetCallback()
 165          * @param array $extOpts
 166          * @param bool $versioned
 167          */
 168         public function testGetWithSetCallback( array $extOpts, $versioned ) {
 169                 $cache = $this->cache;
 170
 171                 $key = wfRandomString();
 172                 $value = wfRandomString();
 173                 $cKey1 = wfRandomString();
 174                 $cKey2 = wfRandomString();
 175
 176                 $priorValue = null;
 177                 $priorAsOf = null;
 178                 $wasSet = 0;
 179                 $func = function( $old, &$ttl, &$opts, $asOf )
 180                 use ( &$wasSet, &$priorValue, &$priorAsOf, $value )
 181                 {
 182                         ++$wasSet;
 183                         $priorValue = $old;
 184                         $priorAsOf = $asOf;
 185                         $ttl = 20; // override with another value
 186                         return $value;
 187                 };
 188
 189                 $wasSet = 0;
 190                 $v = $cache->getWithSetCallback( $key, 30, $func, [ 'lockTSE' => 5 ] + $extOpts );
 191                 $this->assertEquals( $value, $v, "Value returned" );
 192                 $this->assertEquals( 1, $wasSet, "Value regenerated" );
 193                 $this->assertFalse( $priorValue, "No prior value" );
 194                 $this->assertNull( $priorAsOf, "No prior value" );
 195
 196                 $curTTL = null;
 197                 $cache->get( $key, $curTTL );
 198                 $this->assertLessThanOrEqual( 20, $curTTL, 'Current TTL between 19-20 (overriden)' );
 199                 $this->assertGreaterThanOrEqual( 19, $curTTL, 'Current TTL between 19-20 (overriden)' );
 200
 201                 $wasSet = 0;
 202                 $v = $cache->getWithSetCallback( $key, 30, $func, [
 203                                 'lowTTL' => 0,
 204                                 'lockTSE' => 5,
 205                         ] + $extOpts );
 206                 $this->assertEquals( $value, $v, "Value returned" );
 207                 $this->assertEquals( 0, $wasSet, "Value not regenerated" );
 208
 209                 $priorTime = microtime( true );
 210                 usleep( 1 );
 211                 $wasSet = 0;
 212                 $v = $cache->getWithSetCallback(
 213                         $key, 30, $func, [ 'checkKeys' => [ $cKey1, $cKey2 ] ] + $extOpts
 214                 );
 215                 $this->assertEquals( $value, $v, "Value returned" );
 216                 $this->assertEquals( 1, $wasSet, "Value regenerated due to check keys" );
 217                 $this->assertEquals( $value, $priorValue, "Has prior value" );
 218                 $this->assertInternalType( 'float', $priorAsOf, "Has prior value" );
 219                 $t1 = $cache->getCheckKeyTime( $cKey1 );
 220                 $this->assertGreaterThanOrEqual( $priorTime, $t1, 'Check keys generated on miss' );
 221                 $t2 = $cache->getCheckKeyTime( $cKey2 );
 222                 $this->assertGreaterThanOrEqual( $priorTime, $t2, 'Check keys generated on miss' );
 223
 224                 $priorTime = microtime( true );
 225                 $wasSet = 0;
 226                 $v = $cache->getWithSetCallback(
 227                         $key, 30, $func, [ 'checkKeys' => [ $cKey1, $cKey2 ] ] + $extOpts
 228                 );
 229                 $this->assertEquals( $value, $v, "Value returned" );
 230                 $this->assertEquals( 1, $wasSet, "Value regenerated due to still-recent check keys" );
 231                 $t1 = $cache->getCheckKeyTime( $cKey1 );
 232                 $this->assertLessThanOrEqual( $priorTime, $t1, 'Check keys did not change again' );
 233                 $t2 = $cache->getCheckKeyTime( $cKey2 );
 234                 $this->assertLessThanOrEqual( $priorTime, $t2, 'Check keys did not change again' );
 235
 236                 $curTTL = null;
 237                 $v = $cache->get( $key, $curTTL, [ $cKey1, $cKey2 ] );
 238                 if ( $versioned ) {
 239                         $this->assertEquals( $value, $v[$cache::VFLD_DATA], "Value returned" );
 240                 } else {
 241                         $this->assertEquals( $value, $v, "Value returned" );
 242                 }
 243                 $this->assertLessThanOrEqual( 0, $curTTL, "Value has current TTL < 0 due to check keys" );
 244
 245                 $wasSet = 0;
 246                 $key = wfRandomString();
 247                 $v = $cache->getWithSetCallback( $key, 30, $func, [ 'pcTTL' => 5 ] + $extOpts );
 248                 $this->assertEquals( $value, $v, "Value returned" );
 249                 $cache->delete( $key );
 250                 $v = $cache->getWithSetCallback( $key, 30, $func, [ 'pcTTL' => 5 ] + $extOpts );
 251                 $this->assertEquals( $value, $v, "Value still returned after deleted" );
 252                 $this->assertEquals( 1, $wasSet, "Value process cached while deleted" );
 253         }
 254
 255         public static function getWithSetCallback_provider() {
 256                 return [
 257                         [ [], false ],
 258                         [ [ 'version' => 1 ], true ]
 259                 ];
 260         }
 261
 262         /**
 263          * @dataProvider getMultiWithSetCallback_provider
 264          * @covers WANObjectCache::getMultiWithSetCallback()
 265          * @covers WANObjectCache::makeMultiKeys()
 266          * @param array $extOpts
 267          * @param bool $versioned
 268          */
 269         public function testGetMultiWithSetCallback( array $extOpts, $versioned ) {
 270                 $cache = $this->cache;
 271
 272                 $keyA = wfRandomString();
 273                 $keyB = wfRandomString();
 274                 $keyC = wfRandomString();
 275                 $cKey1 = wfRandomString();
 276                 $cKey2 = wfRandomString();
 277
 278                 $priorValue = null;
 279                 $priorAsOf = null;
 280                 $wasSet = 0;
 281                 $genFunc = function ( $id, $old, &$ttl, &$opts, $asOf ) use (
 282                         &$wasSet, &$priorValue, &$priorAsOf
 283                 ) {
 284                         ++$wasSet;
 285                         $priorValue = $old;
 286                         $priorAsOf = $asOf;
 287                         $ttl = 20; // override with another value
 288                         return "@$id$";
 289                 };
 290
 291                 $wasSet = 0;
 292                 $keyedIds = new ArrayIterator( [ $keyA => 3353 ] );
 293                 $value = "@3353$";
 294                 $v = $cache->getMultiWithSetCallback(
 295                         $keyedIds, 30, $genFunc, [ 'lockTSE' => 5 ] + $extOpts );
 296                 $this->assertEquals( $value, $v[$keyA], "Value returned" );
 297                 $this->assertEquals( 1, $wasSet, "Value regenerated" );
 298                 $this->assertFalse( $priorValue, "No prior value" );
 299                 $this->assertNull( $priorAsOf, "No prior value" );
 300
 301                 $curTTL = null;
 302                 $cache->get( $keyA, $curTTL );
 303                 $this->assertLessThanOrEqual( 20, $curTTL, 'Current TTL between 19-20 (overriden)' );
 304                 $this->assertGreaterThanOrEqual( 19, $curTTL, 'Current TTL between 19-20 (overriden)' );
 305
 306                 $wasSet = 0;
 307                 $value = "@efef$";
 308                 $keyedIds = new ArrayIterator( [ $keyB => 'efef' ] );
 309                 $v = $cache->getMultiWithSetCallback(
 310                         $keyedIds, 30, $genFunc, [ 'lowTTL' => 0, 'lockTSE' => 5, ] + $extOpts );
 311                 $this->assertEquals( $value, $v[$keyB], "Value returned" );
 312                 $this->assertEquals( 1, $wasSet, "Value regenerated" );
 313                 $this->assertEquals( 0, $cache->getWarmupKeyMisses(), "Keys warmed yet in process cache" );
 314                 $v = $cache->getMultiWithSetCallback(
 315                         $keyedIds, 30, $genFunc, [ 'lowTTL' => 0, 'lockTSE' => 5, ] + $extOpts );
 316                 $this->assertEquals( $value, $v[$keyB], "Value returned" );
 317                 $this->assertEquals( 1, $wasSet, "Value not regenerated" );
 318                 $this->assertEquals( 0, $cache->getWarmupKeyMisses(), "Keys warmed in process cache" );
 319
 320                 $priorTime = microtime( true );
 321                 usleep( 1 );
 322                 $wasSet = 0;
 323                 $keyedIds = new ArrayIterator( [ $keyB => 'efef' ] );
 324                 $v = $cache->getMultiWithSetCallback(
 325                         $keyedIds, 30, $genFunc, [ 'checkKeys' => [ $cKey1, $cKey2 ] ] + $extOpts
 326                 );
 327                 $this->assertEquals( $value, $v[$keyB], "Value returned" );
 328                 $this->assertEquals( 1, $wasSet, "Value regenerated due to check keys" );
 329                 $this->assertEquals( $value, $priorValue, "Has prior value" );
 330                 $this->assertInternalType( 'float', $priorAsOf, "Has prior value" );
 331                 $t1 = $cache->getCheckKeyTime( $cKey1 );
 332                 $this->assertGreaterThanOrEqual( $priorTime, $t1, 'Check keys generated on miss' );
 333                 $t2 = $cache->getCheckKeyTime( $cKey2 );
 334                 $this->assertGreaterThanOrEqual( $priorTime, $t2, 'Check keys generated on miss' );
 335
 336                 $priorTime = microtime( true );
 337                 $value = "@43636$";
 338                 $wasSet = 0;
 339                 $keyedIds = new ArrayIterator( [ $keyC => 43636 ] );
 340                 $v = $cache->getMultiWithSetCallback(
 341                         $keyedIds, 30, $genFunc, [ 'checkKeys' => [ $cKey1, $cKey2 ] ] + $extOpts
 342                 );
 343                 $this->assertEquals( $value, $v[$keyC], "Value returned" );
 344                 $this->assertEquals( 1, $wasSet, "Value regenerated due to still-recent check keys" );
 345                 $t1 = $cache->getCheckKeyTime( $cKey1 );
 346                 $this->assertLessThanOrEqual( $priorTime, $t1, 'Check keys did not change again' );
 347                 $t2 = $cache->getCheckKeyTime( $cKey2 );
 348                 $this->assertLessThanOrEqual( $priorTime, $t2, 'Check keys did not change again' );
 349
 350                 $curTTL = null;
 351                 $v = $cache->get( $keyC, $curTTL, [ $cKey1, $cKey2 ] );
 352                 if ( $versioned ) {
 353                         $this->assertEquals( $value, $v[$cache::VFLD_DATA], "Value returned" );
 354                 } else {
 355                         $this->assertEquals( $value, $v, "Value returned" );
 356                 }
 357                 $this->assertLessThanOrEqual( 0, $curTTL, "Value has current TTL < 0 due to check keys" );
 358
 359                 $wasSet = 0;
 360                 $key = wfRandomString();
 361                 $keyedIds = new ArrayIterator( [ $key => 242424 ] );
 362                 $v = $cache->getMultiWithSetCallback(
 363                         $keyedIds, 30, $genFunc, [ 'pcTTL' => 5 ] + $extOpts );
 364                 $this->assertEquals( "@{$keyedIds[$key]}$", $v[$key], "Value returned" );
 365                 $cache->delete( $key );
 366                 $keyedIds = new ArrayIterator( [ $key => 242424 ] );
 367                 $v = $cache->getMultiWithSetCallback(
 368                         $keyedIds, 30, $genFunc, [ 'pcTTL' => 5 ] + $extOpts );
 369                 $this->assertEquals( "@{$keyedIds[$key]}$", $v[$key], "Value still returned after deleted" );
 370                 $this->assertEquals( 1, $wasSet, "Value process cached while deleted" );
 371
 372                 $calls = 0;
 373                 $ids = [ 1, 2, 3, 4, 5, 6 ];
 374                 $keyFunc = function ( $id, WANObjectCache $wanCache ) {
 375                         return $wanCache->makeKey( 'test', $id );
 376                 };
 377                 $keyedIds = $cache->makeMultiKeys( $ids, $keyFunc );
 378                 $genFunc = function ( $id, $oldValue, &$ttl, array &$setops ) use ( &$calls ) {
 379                         ++$calls;
 380
 381                         return "val-{$id}";
 382                 };
 383                 $values = $cache->getMultiWithSetCallback( $keyedIds, 10, $genFunc );
 384
 385                 $this->assertEquals(
 386                         [ "val-1", "val-2", "val-3", "val-4", "val-5", "val-6" ],
 387                         array_values( $values ),
 388                         "Correct values in correct order"
 389                 );
 390                 $this->assertEquals(
 391                         array_map( $keyFunc, $ids, array_fill( 0, count( $ids ), $this->cache ) ),
 392                         array_keys( $values ),
 393                         "Correct keys in correct order"
 394                 );
 395                 $this->assertEquals( count( $ids ), $calls );
 396
 397                 $cache->getMultiWithSetCallback( $keyedIds, 10, $genFunc );
 398                 $this->assertEquals( count( $ids ), $calls, "Values cached" );
 399         }
 400
 401         public static function getMultiWithSetCallback_provider() {
 402                 return [
 403                         [ [], false ],
 404                         [ [ 'version' => 1 ], true ]
 405                 ];
 406         }
 407
 408         /**
 409          * @covers WANObjectCache::getWithSetCallback()
 410          * @covers WANObjectCache::doGetWithSetCallback()
 411          */
 412         public function testLockTSE() {
 413                 $cache = $this->cache;
 414                 $key = wfRandomString();
 415                 $value = wfRandomString();
 416
 417                 $calls = 0;
 418                 $func = function() use ( &$calls, $value, $cache, $key ) {
 419                         ++$calls;
 420                         // Immediately kill any mutex rather than waiting a second
 421                         $cache->delete( $cache::MUTEX_KEY_PREFIX . $key );
 422                         return $value;
 423                 };
 424
 425                 $ret = $cache->getWithSetCallback( $key, 30, $func, [ 'lockTSE' => 5 ] );
 426                 $this->assertEquals( $value, $ret );
 427                 $this->assertEquals( 1, $calls, 'Value was populated' );
 428
 429                 // Acquire a lock to verify that getWithSetCallback uses lockTSE properly
 430                 $this->internalCache->add( $cache::MUTEX_KEY_PREFIX . $key, 1, 0 );
 431
 432                 $checkKeys = [ wfRandomString() ]; // new check keys => force misses
 433                 $ret = $cache->getWithSetCallback( $key, 30, $func,
 434                         [ 'lockTSE' => 5, 'checkKeys' => $checkKeys ] );
 435                 $this->assertEquals( $value, $ret, 'Old value used' );
 436                 $this->assertEquals( 1, $calls, 'Callback was not used' );
 437
 438                 $cache->delete( $key );
 439                 $ret = $cache->getWithSetCallback( $key, 30, $func,
 440                         [ 'lockTSE' => 5, 'checkKeys' => $checkKeys ] );
 441                 $this->assertEquals( $value, $ret, 'Callback was used; interim saved' );
 442                 $this->assertEquals( 2, $calls, 'Callback was used; interim saved' );
 443
 444                 $ret = $cache->getWithSetCallback( $key, 30, $func,
 445                         [ 'lockTSE' => 5, 'checkKeys' => $checkKeys ] );
 446                 $this->assertEquals( $value, $ret, 'Callback was not used; used interim' );
 447                 $this->assertEquals( 2, $calls, 'Callback was not used; used interim' );
 448         }
 449
 450         /**
 451          * @covers WANObjectCache::getWithSetCallback()
 452          * @covers WANObjectCache::doGetWithSetCallback()
 453          */
 454         public function testLockTSESlow() {
 455                 $cache = $this->cache;
 456                 $key = wfRandomString();
 457                 $value = wfRandomString();
 458
 459                 $calls = 0;
 460                 $func = function( $oldValue, &$ttl, &$setOpts ) use ( &$calls, $value, $cache, $key ) {
 461                         ++$calls;
 462                         $setOpts['since'] = microtime( true ) - 10;
 463                         // Immediately kill any mutex rather than waiting a second
 464                         $cache->delete( $cache::MUTEX_KEY_PREFIX . $key );
 465                         return $value;
 466                 };
 467
 468                 // Value should be marked as stale due to snapshot lag
 469                 $curTTL = null;
 470                 $ret = $cache->getWithSetCallback( $key, 30, $func, [ 'lockTSE' => 5 ] );
 471                 $this->assertEquals( $value, $ret );
 472                 $this->assertEquals( $value, $cache->get( $key, $curTTL ), 'Value was populated' );
 473                 $this->assertLessThan( 0, $curTTL, 'Value has negative curTTL' );
 474                 $this->assertEquals( 1, $calls, 'Value was generated' );
 475
 476                 // Acquire a lock to verify that getWithSetCallback uses lockTSE properly
 477                 $this->internalCache->add( $cache::MUTEX_KEY_PREFIX . $key, 1, 0 );
 478                 $ret = $cache->getWithSetCallback( $key, 30, $func, [ 'lockTSE' => 5 ] );
 479                 $this->assertEquals( $value, $ret );
 480                 $this->assertEquals( 1, $calls, 'Callback was not used' );
 481         }
 482
 483         /**
 484          * @covers WANObjectCache::getWithSetCallback()
 485          * @covers WANObjectCache::doGetWithSetCallback()
 486          */
 487         public function testBusyValue() {
 488                 $cache = $this->cache;
 489                 $key = wfRandomString();
 490                 $value = wfRandomString();
 491                 $busyValue = wfRandomString();
 492
 493                 $calls = 0;
 494                 $func = function() use ( &$calls, $value, $cache, $key ) {
 495                         ++$calls;
 496                         // Immediately kill any mutex rather than waiting a second
 497                         $cache->delete( $cache::MUTEX_KEY_PREFIX . $key );
 498                         return $value;
 499                 };
 500
 501                 $ret = $cache->getWithSetCallback( $key, 30, $func, [ 'busyValue' => $busyValue ] );
 502                 $this->assertEquals( $value, $ret );
 503                 $this->assertEquals( 1, $calls, 'Value was populated' );
 504
 505                 // Acquire a lock to verify that getWithSetCallback uses busyValue properly
 506                 $this->internalCache->add( $cache::MUTEX_KEY_PREFIX . $key, 1, 0 );
 507
 508                 $checkKeys = [ wfRandomString() ]; // new check keys => force misses
 509                 $ret = $cache->getWithSetCallback( $key, 30, $func,
 510                         [ 'busyValue' => $busyValue, 'checkKeys' => $checkKeys ] );
 511                 $this->assertEquals( $value, $ret, 'Callback used' );
 512                 $this->assertEquals( 2, $calls, 'Callback used' );
 513
 514                 $ret = $cache->getWithSetCallback( $key, 30, $func,
 515                         [ 'lockTSE' => 30, 'busyValue' => $busyValue, 'checkKeys' => $checkKeys ] );
 516                 $this->assertEquals( $value, $ret, 'Old value used' );
 517                 $this->assertEquals( 2, $calls, 'Callback was not used' );
 518
 519                 $cache->delete( $key ); // no value at all anymore and still locked
 520                 $ret = $cache->getWithSetCallback( $key, 30, $func,
 521                         [ 'busyValue' => $busyValue, 'checkKeys' => $checkKeys ] );
 522                 $this->assertEquals( $busyValue, $ret, 'Callback was not used; used busy value' );
 523                 $this->assertEquals( 2, $calls, 'Callback was not used; used busy value' );
 524
 525                 $this->internalCache->delete( $cache::MUTEX_KEY_PREFIX . $key );
 526                 $ret = $cache->getWithSetCallback( $key, 30, $func,
 527                         [ 'lockTSE' => 30, 'busyValue' => $busyValue, 'checkKeys' => $checkKeys ] );
 528                 $this->assertEquals( $value, $ret, 'Callback was used; saved interim' );
 529                 $this->assertEquals( 3, $calls, 'Callback was used; saved interim' );
 530
 531                 $this->internalCache->add( $cache::MUTEX_KEY_PREFIX . $key, 1, 0 );
 532                 $ret = $cache->getWithSetCallback( $key, 30, $func,
 533                         [ 'busyValue' => $busyValue, 'checkKeys' => $checkKeys ] );
 534                 $this->assertEquals( $value, $ret, 'Callback was not used; used interim' );
 535                 $this->assertEquals( 3, $calls, 'Callback was not used; used interim' );
 536         }
 537
 538         /**
 539          * @covers WANObjectCache::getMulti()
 540          */
 541         public function testGetMulti() {
 542                 $cache = $this->cache;
 543
 544                 $value1 = [ 'this' => 'is', 'a' => 'test' ];
 545                 $value2 = [ 'this' => 'is', 'another' => 'test' ];
 546
 547                 $key1 = wfRandomString();
 548                 $key2 = wfRandomString();
 549                 $key3 = wfRandomString();
 550
 551                 $cache->set( $key1, $value1, 5 );
 552                 $cache->set( $key2, $value2, 10 );
 553
 554                 $curTTLs = [];
 555                 $this->assertEquals(
 556                         [ $key1 => $value1, $key2 => $value2 ],
 557                         $cache->getMulti( [ $key1, $key2, $key3 ], $curTTLs ),
 558                         'Result array populated'
 559                 );
 560
 561                 $this->assertEquals( 2, count( $curTTLs ), "Two current TTLs in array" );
 562                 $this->assertGreaterThan( 0, $curTTLs[$key1], "Key 1 has current TTL > 0" );
 563                 $this->assertGreaterThan( 0, $curTTLs[$key2], "Key 2 has current TTL > 0" );
 564
 565                 $cKey1 = wfRandomString();
 566                 $cKey2 = wfRandomString();
 567
 568                 $priorTime = microtime( true );
 569                 usleep( 1 );
 570                 $curTTLs = [];
 571                 $this->assertEquals(
 572                         [ $key1 => $value1, $key2 => $value2 ],
 573                         $cache->getMulti( [ $key1, $key2, $key3 ], $curTTLs, [ $cKey1, $cKey2 ] ),
 574                         "Result array populated even with new check keys"
 575                 );
 576                 $t1 = $cache->getCheckKeyTime( $cKey1 );
 577                 $this->assertGreaterThanOrEqual( $priorTime, $t1, 'Check key 1 generated on miss' );
 578                 $t2 = $cache->getCheckKeyTime( $cKey2 );
 579                 $this->assertGreaterThanOrEqual( $priorTime, $t2, 'Check key 2 generated on miss' );
 580                 $this->assertEquals( 2, count( $curTTLs ), "Current TTLs array set" );
 581                 $this->assertLessThanOrEqual( 0, $curTTLs[$key1], 'Key 1 has current TTL <= 0' );
 582                 $this->assertLessThanOrEqual( 0, $curTTLs[$key2], 'Key 2 has current TTL <= 0' );
 583
 584                 usleep( 1 );
 585                 $curTTLs = [];
 586                 $this->assertEquals(
 587                         [ $key1 => $value1, $key2 => $value2 ],
 588                         $cache->getMulti( [ $key1, $key2, $key3 ], $curTTLs, [ $cKey1, $cKey2 ] ),
 589                         "Result array still populated even with new check keys"
 590                 );
 591                 $this->assertEquals( 2, count( $curTTLs ), "Current TTLs still array set" );
 592                 $this->assertLessThan( 0, $curTTLs[$key1], 'Key 1 has negative current TTL' );
 593                 $this->assertLessThan( 0, $curTTLs[$key2], 'Key 2 has negative current TTL' );
 594         }
 595
 596         /**
 597          * @covers WANObjectCache::getMulti()
 598          * @covers WANObjectCache::processCheckKeys()
 599          */
 600         public function testGetMultiCheckKeys() {
 601                 $cache = $this->cache;
 602
 603                 $checkAll = wfRandomString();
 604                 $check1 = wfRandomString();
 605                 $check2 = wfRandomString();
 606                 $check3 = wfRandomString();
 607                 $value1 = wfRandomString();
 608                 $value2 = wfRandomString();
 609
 610                 // Fake initial check key to be set in the past. Otherwise we'd have to sleep for
 611                 // several seconds during the test to assert the behaviour.
 612                 foreach ( [ $checkAll, $check1, $check2 ] as $checkKey ) {
 613                         $cache->touchCheckKey( $checkKey, WANObjectCache::HOLDOFF_NONE );
 614                 }
 615                 usleep( 100 );
 616
 617                 $cache->set( 'key1', $value1, 10 );
 618                 $cache->set( 'key2', $value2, 10 );
 619
 620                 $curTTLs = [];
 621                 $result = $cache->getMulti( [ 'key1', 'key2', 'key3' ], $curTTLs, [
 622                         'key1' => $check1,
 623                         $checkAll,
 624                         'key2' => $check2,
 625                         'key3' => $check3,
 626                 ] );
 627                 $this->assertEquals(
 628                         [ 'key1' => $value1, 'key2' => $value2 ],
 629                         $result,
 630                         'Initial values'
 631                 );
 632                 $this->assertGreaterThanOrEqual( 9.5, $curTTLs['key1'], 'Initial ttls' );
 633                 $this->assertLessThanOrEqual( 10.5, $curTTLs['key1'], 'Initial ttls' );
 634                 $this->assertGreaterThanOrEqual( 9.5, $curTTLs['key2'], 'Initial ttls' );
 635                 $this->assertLessThanOrEqual( 10.5, $curTTLs['key2'], 'Initial ttls' );
 636
 637                 $cache->touchCheckKey( $check1 );
 638
 639                 $curTTLs = [];
 640                 $result = $cache->getMulti( [ 'key1', 'key2', 'key3' ], $curTTLs, [
 641                         'key1' => $check1,
 642                         $checkAll,
 643                         'key2' => $check2,
 644                         'key3' => $check3,
 645                 ] );
 646                 $this->assertEquals(
 647                         [ 'key1' => $value1, 'key2' => $value2 ],
 648                         $result,
 649                         'key1 expired by check1, but value still provided'
 650                 );
 651                 $this->assertLessThan( 0, $curTTLs['key1'], 'key1 TTL expired' );
 652                 $this->assertGreaterThan( 0, $curTTLs['key2'], 'key2 still valid' );
 653
 654                 $cache->touchCheckKey( $checkAll );
 655
 656                 $curTTLs = [];
 657                 $result = $cache->getMulti( [ 'key1', 'key2', 'key3' ], $curTTLs, [
 658                         'key1' => $check1,
 659                         $checkAll,
 660                         'key2' => $check2,
 661                         'key3' => $check3,
 662                 ] );
 663                 $this->assertEquals(
 664                         [ 'key1' => $value1, 'key2' => $value2 ],
 665                         $result,
 666                         'All keys expired by checkAll, but value still provided'
 667                 );
 668                 $this->assertLessThan( 0, $curTTLs['key1'], 'key1 expired by checkAll' );
 669                 $this->assertLessThan( 0, $curTTLs['key2'], 'key2 expired by checkAll' );
 670         }
 671
 672         /**
 673          * @covers WANObjectCache::get()
 674          * @covers WANObjectCache::processCheckKeys()
 675          */
 676         public function testCheckKeyInitHoldoff() {
 677                 $cache = $this->cache;
 678
 679                 for ( $i = 0; $i < 500; ++$i ) {
 680                         $key = wfRandomString();
 681                         $checkKey = wfRandomString();
 682                         // miss, set, hit
 683                         $cache->get( $key, $curTTL, [ $checkKey ] );
 684                         $cache->set( $key, 'val', 10 );
 685                         $curTTL = null;
 686                         $v = $cache->get( $key, $curTTL, [ $checkKey ] );
 687
 688                         $this->assertEquals( 'val', $v );
 689                         $this->assertLessThan( 0, $curTTL, "Step $i: CTL < 0 (miss/set/hit)" );
 690                 }
 691
 692                 for ( $i = 0; $i < 500; ++$i ) {
 693                         $key = wfRandomString();
 694                         $checkKey = wfRandomString();
 695                         // set, hit
 696                         $cache->set( $key, 'val', 10 );
 697                         $curTTL = null;
 698                         $v = $cache->get( $key, $curTTL, [ $checkKey ] );
 699
 700                         $this->assertEquals( 'val', $v );
 701                         $this->assertLessThan( 0, $curTTL, "Step $i: CTL < 0 (set/hit)" );
 702                 }
 703         }
 704
 705         /**
 706          * @covers WANObjectCache::delete()
 707          */
 708         public function testDelete() {
 709                 $key = wfRandomString();
 710                 $value = wfRandomString();
 711                 $this->cache->set( $key, $value );
 712
 713                 $curTTL = null;
 714                 $v = $this->cache->get( $key, $curTTL );
 715                 $this->assertEquals( $value, $v, "Key was created with value" );
 716                 $this->assertGreaterThan( 0, $curTTL, "Existing key has current TTL > 0" );
 717
 718                 $this->cache->delete( $key );
 719
 720                 $curTTL = null;
 721                 $v = $this->cache->get( $key, $curTTL );
 722                 $this->assertFalse( $v, "Deleted key has false value" );
 723                 $this->assertLessThan( 0, $curTTL, "Deleted key has current TTL < 0" );
 724
 725                 $this->cache->set( $key, $value . 'more' );
 726                 $v = $this->cache->get( $key, $curTTL );
 727                 $this->assertFalse( $v, "Deleted key is tombstoned and has false value" );
 728                 $this->assertLessThan( 0, $curTTL, "Deleted key is tombstoned and has current TTL < 0" );
 729
 730                 $this->cache->set( $key, $value );
 731                 $this->cache->delete( $key, WANObjectCache::HOLDOFF_NONE );
 732
 733                 $curTTL = null;
 734                 $v = $this->cache->get( $key, $curTTL );
 735                 $this->assertFalse( $v, "Deleted key has false value" );
 736                 $this->assertNull( $curTTL, "Deleted key has null current TTL" );
 737
 738                 $this->cache->set( $key, $value );
 739                 $v = $this->cache->get( $key, $curTTL );
 740                 $this->assertEquals( $value, $v, "Key was created with value" );
 741                 $this->assertGreaterThan( 0, $curTTL, "Existing key has current TTL > 0" );
 742         }
 743
 744         /**
 745          * @dataProvider getWithSetCallback_versions_provider
 746          * @param array $extOpts
 747          * @param $versioned
 748          */
 749         public function testGetWithSetCallback_versions( array $extOpts, $versioned ) {
 750                 $cache = $this->cache;
 751
 752                 $key = wfRandomString();
 753                 $value = wfRandomString();
 754
 755                 $wasSet = 0;
 756                 $func = function( $old, &$ttl ) use ( &$wasSet, $value ) {
 757                         ++$wasSet;
 758                         return $value;
 759                 };
 760
 761                 // Set the main key (version N if versioned)
 762                 $wasSet = 0;
 763                 $v = $cache->getWithSetCallback( $key, 30, $func, $extOpts );
 764                 $this->assertEquals( $value, $v, "Value returned" );
 765                 $this->assertEquals( 1, $wasSet, "Value regenerated" );
 766                 $cache->getWithSetCallback( $key, 30, $func, $extOpts );
 767                 $this->assertEquals( 1, $wasSet, "Value not regenerated" );
 768                 // Set the key for version N+1 (if versioned)
 769                 if ( $versioned ) {
 770                         $verOpts = [ 'version' => $extOpts['version'] + 1 ];
 771
 772                         $wasSet = 0;
 773                         $v = $cache->getWithSetCallback( $key, 30, $func, $verOpts + $extOpts );
 774                         $this->assertEquals( $value, $v, "Value returned" );
 775                         $this->assertEquals( 1, $wasSet, "Value regenerated" );
 776
 777                         $wasSet = 0;
 778                         $v = $cache->getWithSetCallback( $key, 30, $func, $verOpts + $extOpts );
 779                         $this->assertEquals( $value, $v, "Value returned" );
 780                         $this->assertEquals( 0, $wasSet, "Value not regenerated" );
 781                 }
 782
 783                 $wasSet = 0;
 784                 $cache->getWithSetCallback( $key, 30, $func, $extOpts );
 785                 $this->assertEquals( 0, $wasSet, "Value not regenerated" );
 786
 787                 $wasSet = 0;
 788                 $cache->delete( $key );
 789                 $v = $cache->getWithSetCallback( $key, 30, $func, $extOpts );
 790                 $this->assertEquals( $value, $v, "Value returned" );
 791                 $this->assertEquals( 1, $wasSet, "Value regenerated" );
 792
 793                 if ( $versioned ) {
 794                         $wasSet = 0;
 795                         $verOpts = [ 'version' => $extOpts['version'] + 1 ];
 796                         $v = $cache->getWithSetCallback( $key, 30, $func, $verOpts + $extOpts );
 797                         $this->assertEquals( $value, $v, "Value returned" );
 798                         $this->assertEquals( 1, $wasSet, "Value regenerated" );
 799                 }
 800         }
 801
 802         public static function getWithSetCallback_versions_provider() {
 803                 return [
 804                         [ [], false ],
 805                         [ [ 'version' => 1 ], true ]
 806                 ];
 807         }
 808
 809         /**
 810          * @covers WANObjectCache::touchCheckKey()
 811          * @covers WANObjectCache::resetCheckKey()
 812          * @covers WANObjectCache::getCheckKeyTime()
 813          */
 814         public function testTouchKeys() {
 815                 $key = wfRandomString();
 816
 817                 $priorTime = microtime( true );
 818                 usleep( 100 );
 819                 $t0 = $this->cache->getCheckKeyTime( $key );
 820                 $this->assertGreaterThanOrEqual( $priorTime, $t0, 'Check key auto-created' );
 821
 822                 $priorTime = microtime( true );
 823                 usleep( 100 );
 824                 $this->cache->touchCheckKey( $key );
 825                 $t1 = $this->cache->getCheckKeyTime( $key );
 826                 $this->assertGreaterThanOrEqual( $priorTime, $t1, 'Check key created' );
 827
 828                 $t2 = $this->cache->getCheckKeyTime( $key );
 829                 $this->assertEquals( $t1, $t2, 'Check key time did not change' );
 830
 831                 usleep( 100 );
 832                 $this->cache->touchCheckKey( $key );
 833                 $t3 = $this->cache->getCheckKeyTime( $key );
 834                 $this->assertGreaterThan( $t2, $t3, 'Check key time increased' );
 835
 836                 $t4 = $this->cache->getCheckKeyTime( $key );
 837                 $this->assertEquals( $t3, $t4, 'Check key time did not change' );
 838
 839                 usleep( 100 );
 840                 $this->cache->resetCheckKey( $key );
 841                 $t5 = $this->cache->getCheckKeyTime( $key );
 842                 $this->assertGreaterThan( $t4, $t5, 'Check key time increased' );
 843
 844                 $t6 = $this->cache->getCheckKeyTime( $key );
 845                 $this->assertEquals( $t5, $t6, 'Check key time did not change' );
 846         }
 847
 848         /**
 849          * @covers WANObjectCache::getMulti()
 850          */
 851         public function testGetWithSeveralCheckKeys() {
 852                 $key = wfRandomString();
 853                 $tKey1 = wfRandomString();
 854                 $tKey2 = wfRandomString();
 855                 $value = 'meow';
 856
 857                 // Two check keys are newer (given hold-off) than $key, another is older
 858                 $this->internalCache->set(
 859                         WANObjectCache::TIME_KEY_PREFIX . $tKey2,
 860                         WANObjectCache::PURGE_VAL_PREFIX . ( microtime( true ) - 3 )
 861                 );
 862                 $this->internalCache->set(
 863                         WANObjectCache::TIME_KEY_PREFIX . $tKey2,
 864                         WANObjectCache::PURGE_VAL_PREFIX . ( microtime( true ) - 5 )
 865                 );
 866                 $this->internalCache->set(
 867                         WANObjectCache::TIME_KEY_PREFIX . $tKey1,
 868                         WANObjectCache::PURGE_VAL_PREFIX . ( microtime( true ) - 30 )
 869                 );
 870                 $this->cache->set( $key, $value, 30 );
 871
 872                 $curTTL = null;
 873                 $v = $this->cache->get( $key, $curTTL, [ $tKey1, $tKey2 ] );
 874                 $this->assertEquals( $value, $v, "Value matches" );
 875                 $this->assertLessThan( -4.9, $curTTL, "Correct CTL" );
 876                 $this->assertGreaterThan( -5.1, $curTTL, "Correct CTL" );
 877         }
 878
 879         /**
 880          * @covers WANObjectCache::reap()
 881          * @covers WANObjectCache::reapCheckKey()
 882          */
 883         public function testReap() {
 884                 $vKey1 = wfRandomString();
 885                 $vKey2 = wfRandomString();
 886                 $tKey1 = wfRandomString();
 887                 $tKey2 = wfRandomString();
 888                 $value = 'moo';
 889
 890                 $knownPurge = time() - 60;
 891                 $goodTime = microtime( true ) - 5;
 892                 $badTime = microtime( true ) - 300;
 893
 894                 $this->internalCache->set(
 895                         WANObjectCache::VALUE_KEY_PREFIX . $vKey1,
 896                         [
 897                                 WANObjectCache::FLD_VERSION => WANObjectCache::VERSION,
 898                                 WANObjectCache::FLD_VALUE => $value,
 899                                 WANObjectCache::FLD_TTL => 3600,
 900                                 WANObjectCache::FLD_TIME => $goodTime
 901                         ]
 902                 );
 903                 $this->internalCache->set(
 904                         WANObjectCache::VALUE_KEY_PREFIX . $vKey2,
 905                         [
 906                                 WANObjectCache::FLD_VERSION => WANObjectCache::VERSION,
 907                                 WANObjectCache::FLD_VALUE => $value,
 908                                 WANObjectCache::FLD_TTL => 3600,
 909                                 WANObjectCache::FLD_TIME => $badTime
 910                         ]
 911                 );
 912                 $this->internalCache->set(
 913                         WANObjectCache::TIME_KEY_PREFIX . $tKey1,
 914                         WANObjectCache::PURGE_VAL_PREFIX . $goodTime
 915                 );
 916                 $this->internalCache->set(
 917                         WANObjectCache::TIME_KEY_PREFIX . $tKey2,
 918                         WANObjectCache::PURGE_VAL_PREFIX . $badTime
 919                 );
 920
 921                 $this->assertEquals( $value, $this->cache->get( $vKey1 ) );
 922                 $this->assertEquals( $value, $this->cache->get( $vKey2 ) );
 923                 $this->cache->reap( $vKey1, $knownPurge, $bad1 );
 924                 $this->cache->reap( $vKey2, $knownPurge, $bad2 );
 925
 926                 $this->assertFalse( $bad1 );
 927                 $this->assertTrue( $bad2 );
 928
 929                 $this->cache->reapCheckKey( $tKey1, $knownPurge, $tBad1 );
 930                 $this->cache->reapCheckKey( $tKey2, $knownPurge, $tBad2 );
 931                 $this->assertFalse( $tBad1 );
 932                 $this->assertTrue( $tBad2 );
 933         }
 934
 935         /**
 936          * @covers WANObjectCache::set()
 937          */
 938         public function testSetWithLag() {
 939                 $value = 1;
 940
 941                 $key = wfRandomString();
 942                 $opts = [ 'lag' => 300, 'since' => microtime( true ) ];
 943                 $this->cache->set( $key, $value, 30, $opts );
 944                 $this->assertEquals( $value, $this->cache->get( $key ), "Rep-lagged value written." );
 945
 946                 $key = wfRandomString();
 947                 $opts = [ 'lag' => 0, 'since' => microtime( true ) - 300 ];
 948                 $this->cache->set( $key, $value, 30, $opts );
 949                 $this->assertEquals( false, $this->cache->get( $key ), "Trx-lagged value not written." );
 950
 951                 $key = wfRandomString();
 952                 $opts = [ 'lag' => 5, 'since' => microtime( true ) - 5 ];
 953                 $this->cache->set( $key, $value, 30, $opts );
 954                 $this->assertEquals( false, $this->cache->get( $key ), "Lagged value not written." );
 955         }
 956
 957         /**
 958          * @covers WANObjectCache::set()
 959          */
 960         public function testWritePending() {
 961                 $value = 1;
 962
 963                 $key = wfRandomString();
 964                 $opts = [ 'pending' => true ];
 965                 $this->cache->set( $key, $value, 30, $opts );
 966                 $this->assertEquals( false, $this->cache->get( $key ), "Pending value not written." );
 967         }
 968
 969         public function testMcRouterSupport() {
 970                 $localBag = $this->getMockBuilder( 'EmptyBagOStuff' )
 971                         ->setMethods( [ 'set', 'delete' ] )->getMock();
 972                 $localBag->expects( $this->never() )->method( 'set' );
 973                 $localBag->expects( $this->never() )->method( 'delete' );
 974                 $wanCache = new WANObjectCache( [
 975                         'cache' => $localBag,
 976                         'pool' => 'testcache-hash',
 977                         'relayer' => new EventRelayerNull( [] )
 978                 ] );
 979                 $valFunc = function () {
 980                         return 1;
 981                 };
 982
 983                 // None of these should use broadcasting commands (e.g. SET, DELETE)
 984                 $wanCache->get( 'x' );
 985                 $wanCache->get( 'x', $ctl, [ 'check1' ] );
 986                 $wanCache->getMulti( [ 'x', 'y' ] );
 987                 $wanCache->getMulti( [ 'x', 'y' ], $ctls, [ 'check2' ] );
 988                 $wanCache->getWithSetCallback( 'p', 30, $valFunc );
 989                 $wanCache->getCheckKeyTime( 'zzz' );
 990                 $wanCache->reap( 'x', time() - 300 );
 991                 $wanCache->reap( 'zzz', time() - 300 );
 992         }
 993
 994         /**
 995          * @dataProvider provideAdaptiveTTL
 996          * @covers WANObjectCache::adaptiveTTL()
 997          * @param float|int $ago
 998          * @param int $maxTTL
 999          * @param int $minTTL
1000          * @param float $factor
1001          * @param int $adaptiveTTL
1002          */
1003         public function testAdaptiveTTL( $ago, $maxTTL, $minTTL, $factor, $adaptiveTTL ) {
1004                 $mtime = $ago ? time() - $ago : $ago;
1005                 $margin = 5;
1006                 $ttl = $this->cache->adaptiveTTL( $mtime, $maxTTL, $minTTL, $factor );
1007
1008                 $this->assertGreaterThanOrEqual( $adaptiveTTL - $margin, $ttl );
1009                 $this->assertLessThanOrEqual( $adaptiveTTL + $margin, $ttl );
1010
1011                 $ttl = $this->cache->adaptiveTTL( (string)$mtime, $maxTTL, $minTTL, $factor );
1012
1013                 $this->assertGreaterThanOrEqual( $adaptiveTTL - $margin, $ttl );
1014                 $this->assertLessThanOrEqual( $adaptiveTTL + $margin, $ttl );
1015         }
1016
1017         public static function provideAdaptiveTTL() {
1018                 return [
1019                         [ 3600, 900, 30, .2, 720 ],
1020                         [ 3600, 500, 30, .2, 500 ],
1021                         [ 3600, 86400, 800, .2, 800 ],
1022                         [ false, 86400, 800, .2, 800 ],
1023                         [ null, 86400, 800, .2, 800 ]
1024                 ];
1025         }
1026 }