*
* Uses URL of the form "baseURL/{KEY}" to store, fetch, and delete values.
*
- * E.g., when base URL is `/v1/sessions/`, then the store would do:
+ * E.g., when base URL is `/sessions/v1`, then the store would do:
*
- * `PUT /v1/sessions/12345758`
+ * `PUT /sessions/v1/12345758`
*
* and fetch would do:
*
- * `GET /v1/sessions/12345758`
+ * `GET /sessions/v1/12345758`
*
* delete would do:
*
- * `DELETE /v1/sessions/12345758`
+ * `DELETE /sessions/v1/12345758`
*
- * Configure with:
+ * Minimal generic configuration:
*
* @code
* $wgObjectCaches['sessions'] = array(
* 'class' => 'RESTBagOStuff',
- * 'url' => 'http://localhost:7231/wikimedia.org/v1/sessions/'
+ * 'url' => 'http://localhost:7231/wikimedia.org/somepath/'
* );
* @endcode
+ *
+ * Configuration for Kask (session storage):
+ * @code
+ * $wgObjectCaches['sessions'] = array(
+ * 'class' => 'RESTBagOStuff',
+ * 'url' => 'https://kaskhost:1234/sessions/v1/',
+ * 'httpParams' => [
+ * 'readHeaders' => [],
+ * 'writeHeaders' => [ 'content-type' => 'application/octet-stream' ],
+ * 'deleteHeaders' => [],
+ * 'writeMethod' => 'POST',
+ * ],
+ * 'extendedErrorBodyFields' => [ 'type', 'title', 'detail', 'instance' ]
+ * );
+ * $wgSessionCacheType = 'sessions';
+ * @endcode
*/
class RESTBagOStuff extends BagOStuff {
/**
*/
private $url;
+ /**
+ * @var array http parameters: readHeaders, writeHeaders, deleteHeaders, writeMethod
+ */
+ private $httpParams;
+
+ /**
+ * @var array additional body fields to log on error, if possible
+ */
+ private $extendedErrorBodyFields;
+
public function __construct( $params ) {
if ( empty( $params['url'] ) ) {
throw new InvalidArgumentException( 'URL parameter is required' );
}
+
if ( empty( $params['client'] ) ) {
// Pass through some params to the HTTP client.
$clientParams = [
} else {
$this->client = $params['client'];
}
+
+ $this->httpParams['writeMethod'] = $params['httpParams']['writeMethod'] ?? 'PUT';
+ $this->httpParams['readHeaders'] = $params['httpParams']['readHeaders'] ?? [];
+ $this->httpParams['writeHeaders'] = $params['httpParams']['writeHeaders'] ?? [];
+ $this->httpParams['deleteHeaders'] = $params['httpParams']['deleteHeaders'] ?? [];
+ $this->extendedErrorBodyFields = $params['extendedErrorBodyFields'] ?? [];
+
// The parent constructor calls setLogger() which sets the logger in $this->client
parent::__construct( $params );
+
// Make sure URL ends with /
$this->url = rtrim( $params['url'], '/' ) . '/';
+
// Default config, R+W > N; no locks on reads though; writes go straight to state-machine
$this->attrMap[self::ATTR_SYNCWRITES] = self::QOS_SYNCWRITES_QC;
}
$req = [
'method' => 'GET',
'url' => $this->url . rawurlencode( $key ),
+ 'headers' => $this->httpParams['readHeaders'],
];
list( $rcode, $rdesc, $rhdrs, $rbody, $rerr ) = $this->client->run( $req );
if ( $rcode === 200 ) {
if ( is_string( $rbody ) ) {
- $value = unserialize( $rbody );
+ $value = $this->decodeBody( $rbody );
/// @FIXME: use some kind of hash or UUID header as CAS token
$casToken = ( $value !== false ) ? $rbody : null;
return false;
}
if ( $rcode === 0 || ( $rcode >= 400 && $rcode != 404 ) ) {
- return $this->handleError( "Failed to fetch $key", $rcode, $rerr );
+ return $this->handleError( "Failed to fetch $key", $rcode, $rerr, $rhdrs, $rbody );
}
return false;
}
// @TODO: respect WRITE_SYNC (e.g. EACH_QUORUM)
// @TODO: respect $exptime
$req = [
- 'method' => 'PUT',
+ 'method' => $this->httpParams['writeMethod'],
'url' => $this->url . rawurlencode( $key ),
- 'body' => serialize( $value )
+ 'body' => $this->encodeBody( $value ),
+ 'headers' => $this->httpParams['writeHeaders'],
];
+
list( $rcode, $rdesc, $rhdrs, $rbody, $rerr ) = $this->client->run( $req );
if ( $rcode === 200 || $rcode === 201 || $rcode === 204 ) {
return true;
}
- return $this->handleError( "Failed to store $key", $rcode, $rerr );
+ return $this->handleError( "Failed to store $key", $rcode, $rerr, $rhdrs, $rbody );
}
public function add( $key, $value, $exptime = 0, $flags = 0 ) {
$req = [
'method' => 'DELETE',
'url' => $this->url . rawurlencode( $key ),
+ 'headers' => $this->httpParams['deleteHeaders'],
];
+
list( $rcode, $rdesc, $rhdrs, $rbody, $rerr ) = $this->client->run( $req );
if ( in_array( $rcode, [ 200, 204, 205, 404, 410 ] ) ) {
return true;
}
- return $this->handleError( "Failed to delete $key", $rcode, $rerr );
+ return $this->handleError( "Failed to delete $key", $rcode, $rerr, $rhdrs, $rbody );
}
public function incr( $key, $value = 1 ) {
return false;
}
+ /**
+ * Processes the response body.
+ *
+ * @param string $body request body to process
+ * @return mixed|bool the processed body, or false on error
+ */
+ private function decodeBody( $body ) {
+ $value = json_decode( $body, true );
+ return ( json_last_error() === JSON_ERROR_NONE ) ? $value : false;
+ }
+
+ /**
+ * Prepares the request body (the "value" portion of our key/value store) for transmission.
+ *
+ * @param string $body request body to prepare
+ * @return string the prepared body, or an empty string on error
+ * @throws LogicException
+ */
+ private function encodeBody( $body ) {
+ $value = json_encode( $body );
+ if ( $value === false ) {
+ throw new InvalidArgumentException( __METHOD__ . ": body could not be encoded." );
+ }
+ return $value;
+ }
+
/**
* Handle storage error
* @param string $msg Error message
* @param int $rcode Error code from client
* @param string $rerr Error message from client
+ * @param array $rhdrs Response headers
+ * @param string $rbody Error body from client (if any)
* @return false
*/
- protected function handleError( $msg, $rcode, $rerr ) {
- $this->logger->error( "$msg : ({code}) {error}", [
+ protected function handleError( $msg, $rcode, $rerr, $rhdrs, $rbody ) {
+ $message = "$msg : ({code}) {error}";
+ $context = [
'code' => $rcode,
'error' => $rerr
- ] );
+ ];
+
+ if ( $this->extendedErrorBodyFields !== [] ) {
+ $body = $this->decodeBody( $rbody );
+ if ( $body ) {
+ $extraFields = '';
+ foreach ( $this->extendedErrorBodyFields as $field ) {
+ if ( isset( $body[$field] ) ) {
+ $extraFields .= " : ({$field}) {$body[$field]}";
+ }
+ }
+ if ( $extraFields !== '' ) {
+ $message .= " {extra_fields}";
+ $context['extra_fields'] = $extraFields;
+ }
+ }
+ }
+
+ $this->logger->error( $message, $context );
$this->setLastError( $rcode === 0 ? self::ERR_UNREACHABLE : self::ERR_UNEXPECTED );
return false;
}
public function testGet() {
$this->client->expects( $this->once() )->method( 'run' )->with( [
'method' => 'GET',
- 'url' => 'http://test/rest/42xyz42'
+ 'url' => 'http://test/rest/42xyz42',
+ 'headers' => []
// list( $rcode, $rdesc, $rhdrs, $rbody, $rerr )
- ] )->willReturn( [ 200, 'OK', [], 's:8:"somedata";', 0 ] );
+ ] )->willReturn( [ 200, 'OK', [], '"somedata"', 0 ] );
$result = $this->bag->get( '42xyz42' );
$this->assertEquals( 'somedata', $result );
}
public function testGetNotExist() {
$this->client->expects( $this->once() )->method( 'run' )->with( [
'method' => 'GET',
- 'url' => 'http://test/rest/42xyz42'
+ 'url' => 'http://test/rest/42xyz42',
+ 'headers' => []
// list( $rcode, $rdesc, $rhdrs, $rbody, $rerr )
] )->willReturn( [ 404, 'Not found', [], 'Nothing to see here', 0 ] );
$result = $this->bag->get( '42xyz42' );
public function testGetBadClient() {
$this->client->expects( $this->once() )->method( 'run' )->with( [
'method' => 'GET',
- 'url' => 'http://test/rest/42xyz42'
+ 'url' => 'http://test/rest/42xyz42',
+ 'headers' => []
// list( $rcode, $rdesc, $rhdrs, $rbody, $rerr )
] )->willReturn( [ 0, '', [], '', 'cURL has failed you today' ] );
$result = $this->bag->get( '42xyz42' );
public function testGetBadServer() {
$this->client->expects( $this->once() )->method( 'run' )->with( [
'method' => 'GET',
- 'url' => 'http://test/rest/42xyz42'
+ 'url' => 'http://test/rest/42xyz42',
+ 'headers' => []
// list( $rcode, $rdesc, $rhdrs, $rbody, $rerr )
] )->willReturn( [ 500, 'Too busy', [], 'Server is too busy', '' ] );
$result = $this->bag->get( '42xyz42' );
$this->client->expects( $this->once() )->method( 'run' )->with( [
'method' => 'PUT',
'url' => 'http://test/rest/42xyz42',
- 'body' => 's:8:"postdata";'
+ 'body' => '"postdata"',
+ 'headers' => []
// list( $rcode, $rdesc, $rhdrs, $rbody, $rerr )
] )->willReturn( [ 200, 'OK', [], 'Done', 0 ] );
$result = $this->bag->set( '42xyz42', 'postdata' );
$this->client->expects( $this->once() )->method( 'run' )->with( [
'method' => 'DELETE',
'url' => 'http://test/rest/42xyz42',
+ 'headers' => []
// list( $rcode, $rdesc, $rhdrs, $rbody, $rerr )
] )->willReturn( [ 200, 'OK', [], 'Done', 0 ] );
$result = $this->bag->delete( '42xyz42' );