MediaWiki REL1_39
FileOpBatch.php
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1<?php
34 /* Timeout related parameters */
35 private const MAX_BATCH_SIZE = 1000; // integer
36
54 public static function attempt( array $performOps, array $opts ) {
55 $status = StatusValue::newGood();
56
57 $n = count( $performOps );
58 if ( $n > self::MAX_BATCH_SIZE ) {
59 $status->fatal( 'backend-fail-batchsize', $n, self::MAX_BATCH_SIZE );
60
61 return $status;
62 }
63
64 $ignoreErrors = !empty( $opts['force'] );
65 $maxConcurrency = $opts['concurrency'] ?? 1;
66
67 $predicates = FileOp::newPredicates(); // account for previous ops in prechecks
68 $curBatch = []; // concurrent FileOp sub-batch accumulation
69 $curBatchDeps = FileOp::newDependencies(); // paths used in FileOp sub-batch
70 $pPerformOps = []; // ordered list of concurrent FileOp sub-batches
71 $lastBackend = null; // last op backend name
72 // Do pre-checks for each operation; abort on failure...
73 foreach ( $performOps as $index => $fileOp ) {
74 $backendName = $fileOp->getBackend()->getName();
75 // Decide if this op can be done concurrently within this sub-batch
76 // or if a new concurrent sub-batch must be started after this one...
77 if ( $fileOp->dependsOn( $curBatchDeps )
78 || count( $curBatch ) >= $maxConcurrency
79 || ( $backendName !== $lastBackend && count( $curBatch ) )
80 ) {
81 $pPerformOps[] = $curBatch; // push this batch
82 $curBatch = []; // start a new sub-batch
83 $curBatchDeps = FileOp::newDependencies();
84 }
85 $lastBackend = $backendName;
86 $curBatch[$index] = $fileOp; // keep index
87 // Update list of affected paths in this batch
88 $curBatchDeps = $fileOp->applyDependencies( $curBatchDeps );
89 // Simulate performing the operation...
90 $oldPredicates = $predicates;
91 $subStatus = $fileOp->precheck( $predicates ); // updates $predicates
92 $status->merge( $subStatus );
93 if ( !$subStatus->isOK() ) {
94 // operation failed?
95 $status->success[$index] = false;
96 ++$status->failCount;
97 if ( !$ignoreErrors ) {
98 return $status; // abort
99 }
100 }
101 }
102 // Push the last sub-batch
103 if ( count( $curBatch ) ) {
104 $pPerformOps[] = $curBatch;
105 }
106
107 if ( $ignoreErrors ) { // treat precheck() fatals as mere warnings
108 $status->setResult( true, $status->value );
109 }
110
111 // Attempt each operation (in parallel if allowed and possible)...
112 self::runParallelBatches( $pPerformOps, $status );
113
114 return $status;
115 }
116
128 protected static function runParallelBatches( array $pPerformOps, StatusValue $status ) {
129 $aborted = false; // set to true on unexpected errors
130 foreach ( $pPerformOps as $performOpsBatch ) {
131 if ( $aborted ) { // check batch op abort flag...
132 // We can't continue (even with $ignoreErrors) as $predicates is wrong.
133 // Log the remaining ops as failed for recovery...
134 foreach ( $performOpsBatch as $i => $fileOp ) {
135 $status->success[$i] = false;
136 ++$status->failCount;
137 $fileOp->logFailure( 'attempt_aborted' );
138 }
139 continue;
140 }
142 $statuses = [];
143 $opHandles = [];
144 // Get the backend; all sub-batch ops belong to a single backend
146 $backend = reset( $performOpsBatch )->getBackend();
147 // Get the operation handles or actually do it if there is just one.
148 // If attemptAsync() returns a StatusValue, it was either due to an error
149 // or the backend does not support async ops and did it synchronously.
150 foreach ( $performOpsBatch as $i => $fileOp ) {
151 if ( !isset( $status->success[$i] ) ) { // didn't already fail in precheck()
152 // Parallel ops may be disabled in config due to missing dependencies,
153 // (e.g. needing popen()). When they are, $performOpsBatch has size 1.
154 $subStatus = ( count( $performOpsBatch ) > 1 )
155 ? $fileOp->attemptAsync()
156 : $fileOp->attempt();
157 if ( $subStatus->value instanceof FileBackendStoreOpHandle ) {
158 $opHandles[$i] = $subStatus->value; // deferred
159 } else {
160 $statuses[$i] = $subStatus; // done already
161 }
162 }
163 }
164 // Try to do all the operations concurrently...
165 $statuses += $backend->executeOpHandlesInternal( $opHandles );
166 // Marshall and merge all the responses (blocking)...
167 foreach ( $performOpsBatch as $i => $fileOp ) {
168 if ( !isset( $status->success[$i] ) ) { // didn't already fail in precheck()
169 $subStatus = $statuses[$i];
170 $status->merge( $subStatus );
171 if ( $subStatus->isOK() ) {
172 $status->success[$i] = true;
173 ++$status->successCount;
174 } else {
175 $status->success[$i] = false;
176 ++$status->failCount;
177 $aborted = true; // set abort flag; we can't continue
178 }
179 }
180 }
181 }
182 }
183}
FileBackendStore helper class for performing asynchronous file operations.
Helper class for representing batch file operations.
static runParallelBatches(array $pPerformOps, StatusValue $status)
Attempt a list of file operations sub-batches in series.
static attempt(array $performOps, array $opts)
Attempt to perform a series of file operations.
static newDependencies()
Get a new empty dependency tracking array for paths read/written to.
Definition FileOp.php:158
static newPredicates()
Get a new empty predicates array for precheck()
Definition FileOp.php:149
Generic operation result class Has warning/error list, boolean status and arbitrary value.
merge( $other, $overwriteValue=false)
Merge another status object into this one.