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RESTBagOStuff.php
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1 <?php
2 
4 
54  const DEFAULT_CONN_TIMEOUT = 1.2;
55 
59  const DEFAULT_REQ_TIMEOUT = 3.0;
60 
64  private $client;
65 
70  private $url;
71 
75  private $httpParams;
76 
85 
91  private $hmacKey;
92 
97 
98  public function __construct( $params ) {
99  $params['segmentationSize'] = $params['segmentationSize'] ?? INF;
100  if ( empty( $params['url'] ) ) {
101  throw new InvalidArgumentException( 'URL parameter is required' );
102  }
103 
104  if ( empty( $params['client'] ) ) {
105  // Pass through some params to the HTTP client.
106  $clientParams = [
107  'connTimeout' => $params['connTimeout'] ?? self::DEFAULT_CONN_TIMEOUT,
108  'reqTimeout' => $params['reqTimeout'] ?? self::DEFAULT_REQ_TIMEOUT,
109  ];
110  foreach ( [ 'caBundlePath', 'proxy' ] as $key ) {
111  if ( isset( $params[$key] ) ) {
112  $clientParams[$key] = $params[$key];
113  }
114  }
115  $this->client = new MultiHttpClient( $clientParams );
116  } else {
117  $this->client = $params['client'];
118  }
119 
120  $this->httpParams['writeMethod'] = $params['httpParams']['writeMethod'] ?? 'PUT';
121  $this->httpParams['readHeaders'] = $params['httpParams']['readHeaders'] ?? [];
122  $this->httpParams['writeHeaders'] = $params['httpParams']['writeHeaders'] ?? [];
123  $this->httpParams['deleteHeaders'] = $params['httpParams']['deleteHeaders'] ?? [];
124  $this->extendedErrorBodyFields = $params['extendedErrorBodyFields'] ?? [];
125  $this->serializationType = $params['serialization_type'] ?? 'legacy';
126  $this->hmacKey = $params['hmac_key'] ?? '';
127 
128  // The parent constructor calls setLogger() which sets the logger in $this->client
129  parent::__construct( $params );
130 
131  // Make sure URL ends with /
132  $this->url = rtrim( $params['url'], '/' ) . '/';
133 
134  // Default config, R+W > N; no locks on reads though; writes go straight to state-machine
135  $this->attrMap[self::ATTR_SYNCWRITES] = self::QOS_SYNCWRITES_QC;
136  }
137 
138  public function setLogger( LoggerInterface $logger ) {
139  parent::setLogger( $logger );
140  $this->client->setLogger( $logger );
141  }
142 
143  protected function doGet( $key, $flags = 0, &$casToken = null ) {
144  $casToken = null;
145 
146  $req = [
147  'method' => 'GET',
148  'url' => $this->url . rawurlencode( $key ),
149  'headers' => $this->httpParams['readHeaders'],
150  ];
151 
152  list( $rcode, $rdesc, $rhdrs, $rbody, $rerr ) = $this->client->run( $req );
153  if ( $rcode === 200 ) {
154  if ( is_string( $rbody ) ) {
155  $value = $this->decodeBody( $rbody );
157  $casToken = ( $value !== false ) ? $rbody : null;
158 
159  return $value;
160  }
161  return false;
162  }
163  if ( $rcode === 0 || ( $rcode >= 400 && $rcode != 404 ) ) {
164  return $this->handleError( "Failed to fetch $key", $rcode, $rerr, $rhdrs, $rbody );
165  }
166  return false;
167  }
168 
169  protected function doSet( $key, $value, $exptime = 0, $flags = 0 ) {
170  // @TODO: respect WRITE_SYNC (e.g. EACH_QUORUM)
171  // @TODO: respect $exptime
172  $req = [
173  'method' => $this->httpParams['writeMethod'],
174  'url' => $this->url . rawurlencode( $key ),
175  'body' => $this->encodeBody( $value ),
176  'headers' => $this->httpParams['writeHeaders'],
177  ];
178 
179  list( $rcode, $rdesc, $rhdrs, $rbody, $rerr ) = $this->client->run( $req );
180  if ( $rcode === 200 || $rcode === 201 || $rcode === 204 ) {
181  return true;
182  }
183  return $this->handleError( "Failed to store $key", $rcode, $rerr, $rhdrs, $rbody );
184  }
185 
186  protected function doAdd( $key, $value, $exptime = 0, $flags = 0 ) {
187  // @TODO: make this atomic
188  if ( $this->get( $key ) === false ) {
189  return $this->set( $key, $value, $exptime, $flags );
190  }
191 
192  return false; // key already set
193  }
194 
195  protected function doDelete( $key, $flags = 0 ) {
196  // @TODO: respect WRITE_SYNC (e.g. EACH_QUORUM)
197  $req = [
198  'method' => 'DELETE',
199  'url' => $this->url . rawurlencode( $key ),
200  'headers' => $this->httpParams['deleteHeaders'],
201  ];
202 
203  list( $rcode, $rdesc, $rhdrs, $rbody, $rerr ) = $this->client->run( $req );
204  if ( in_array( $rcode, [ 200, 204, 205, 404, 410 ] ) ) {
205  return true;
206  }
207  return $this->handleError( "Failed to delete $key", $rcode, $rerr, $rhdrs, $rbody );
208  }
209 
210  public function incr( $key, $value = 1, $flags = 0 ) {
211  // @TODO: make this atomic
212  $n = $this->get( $key, self::READ_LATEST );
213  if ( $this->isInteger( $n ) ) { // key exists?
214  $n = max( $n + (int)$value, 0 );
215  // @TODO: respect $exptime
216  return $this->set( $key, $n ) ? $n : false;
217  }
218 
219  return false;
220  }
221 
222  public function decr( $key, $value = 1, $flags = 0 ) {
223  return $this->incr( $key, -$value, $flags );
224  }
225 
232  private function decodeBody( $body ) {
233  if ( $this->serializationType === 'legacy' ) {
234  $serialized = $body;
235  } else {
236  $pieces = explode( '.', $body, 3 );
237  if ( count( $pieces ) !== 3 || $pieces[0] !== $this->serializationType ) {
238  return false;
239  }
240  list( , $hmac, $serialized ) = $pieces;
241  if ( $this->hmacKey !== '' ) {
242  $checkHmac = hash_hmac( 'sha256', $serialized, $this->hmacKey, true );
243  if ( !hash_equals( $checkHmac, base64_decode( $hmac ) ) ) {
244  return false;
245  }
246  }
247  }
248 
249  switch ( $this->serializationType ) {
250  case 'JSON':
251  $value = json_decode( $serialized, true );
252  return ( json_last_error() === JSON_ERROR_NONE ) ? $value : false;
253 
254  case 'PHP':
255  case 'legacy':
256  return unserialize( $serialized );
257 
258  default:
259  throw new \DomainException(
260  "Unknown serialization type: $this->serializationType"
261  );
262  }
263  }
264 
272  private function encodeBody( $body ) {
273  switch ( $this->serializationType ) {
274  case 'JSON':
275  $value = json_encode( $body );
276  if ( $value === false ) {
277  throw new InvalidArgumentException( __METHOD__ . ": body could not be encoded." );
278  }
279  break;
280 
281  case 'PHP':
282  case "legacy":
283  $value = serialize( $body );
284  break;
285 
286  default:
287  throw new \DomainException(
288  "Unknown serialization type: $this->serializationType"
289  );
290  }
291 
292  if ( $this->serializationType !== 'legacy' ) {
293  if ( $this->hmacKey !== '' ) {
294  $hmac = base64_encode(
295  hash_hmac( 'sha256', $value, $this->hmacKey, true )
296  );
297  } else {
298  $hmac = '';
299  }
300  $value = $this->serializationType . '.' . $hmac . '.' . $value;
301  }
302 
303  return $value;
304  }
305 
315  protected function handleError( $msg, $rcode, $rerr, $rhdrs, $rbody ) {
316  $message = "$msg : ({code}) {error}";
317  $context = [
318  'code' => $rcode,
319  'error' => $rerr
320  ];
321 
322  if ( $this->extendedErrorBodyFields !== [] ) {
323  $body = $this->decodeBody( $rbody );
324  if ( $body ) {
325  $extraFields = '';
326  foreach ( $this->extendedErrorBodyFields as $field ) {
327  if ( isset( $body[$field] ) ) {
328  $extraFields .= " : ({$field}) {$body[$field]}";
329  }
330  }
331  if ( $extraFields !== '' ) {
332  $message .= " {extra_fields}";
333  $context['extra_fields'] = $extraFields;
334  }
335  }
336  }
337 
338  $this->logger->error( $message, $context );
339  $this->setLastError( $rcode === 0 ? self::ERR_UNREACHABLE : self::ERR_UNEXPECTED );
340  return false;
341  }
342 }
MultiHttpClient $client
$context
Definition: load.php:45
doDelete( $key, $flags=0)
__construct( $params)
string $hmacKey
Optional HMAC Key for protecting the serialized blob.
decodeBody( $body)
Processes the response body.
handleError( $msg, $rcode, $rerr, $rhdrs, $rbody)
Handle storage error.
string $serializationType
Optional serialization type to use.
const DEFAULT_CONN_TIMEOUT
Default connection timeout in seconds.
incr( $key, $value=1, $flags=0)
doGet( $key, $flags=0, &$casToken=null)
Storage medium specific cache for storing items (e.g.
array $httpParams
http parameters: readHeaders, writeHeaders, deleteHeaders, writeMethod
array $extendedErrorBodyFields
additional body fields to log on error, if possible
Interface to key-value storage behind an HTTP server.
decr( $key, $value=1, $flags=0)
LoggerInterface $logger
Definition: BagOStuff.php:65
encodeBody( $body)
Prepares the request body (the "value" portion of our key/value store) for transmission.
doSet( $key, $value, $exptime=0, $flags=0)
setLastError( $err)
Set the "last error" registry.
const DEFAULT_REQ_TIMEOUT
Default request timeout.
doAdd( $key, $value, $exptime=0, $flags=0)
foreach( $res as $row) $serialized
isInteger( $value)
Check if a value is an integer.
Class to handle multiple HTTP requests.
string $url
REST URL to use for storage.
setLogger(LoggerInterface $logger)