Initial checkin of gRPC to third_party/

third_party/grpc/src/php/lib/Grpc/BaseStub.php

Index: third_party/grpc/src/php/lib/Grpc/BaseStub.php
diff --git a/third_party/grpc/src/php/lib/Grpc/BaseStub.php b/third_party/grpc/src/php/lib/Grpc/BaseStub.php
new file mode 100644
index 0000000000000000000000000000000000000000..2de1b337e53260a458f489a5725abf853ebfcbac
--- /dev/null
+++ b/third_party/grpc/src/php/lib/Grpc/BaseStub.php
@@ -0,0 +1,324 @@
+<?php
+/*
+ *
+ * Copyright 2015, Google Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ *     * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+namespace Grpc;
+
+/**
+ * Base class for generated client stubs. Stub methods are expected to call
+ * _simpleRequest or _streamRequest and return the result.
+ */
+class BaseStub
+{
+    private $hostname;
+    private $channel;
+
+    // a callback function
+    private $update_metadata;
+
+    /**
+     * @param $hostname string
+     * @param $opts array
+     *  - 'update_metadata': (optional) a callback function which takes in a
+     * metadata array, and returns an updated metadata array
+     *  - 'grpc.primary_user_agent': (optional) a user-agent string
+     */
+    public function __construct($hostname, $opts)
+    {
+        $this->hostname = $hostname;
+        $this->update_metadata = null;
+        if (isset($opts['update_metadata'])) {
+            if (is_callable($opts['update_metadata'])) {
+                $this->update_metadata = $opts['update_metadata'];
+            }
+            unset($opts['update_metadata']);
+        }
+        $package_config = json_decode(
+            file_get_contents(dirname(__FILE__).'/../../composer.json'), true);
+        if (!empty($opts['grpc.primary_user_agent'])) {
+            $opts['grpc.primary_user_agent'] .= ' ';
+        } else {
+            $opts['grpc.primary_user_agent'] = '';
+        }
+        $opts['grpc.primary_user_agent'] .=
+            'grpc-php/'.$package_config['version'];
+        if (!array_key_exists('credentials', $opts)) {
+            throw new \Exception("The opts['credentials'] key is now ".
+                                 'required. Please see one of the '.
+                                 'ChannelCredentials::create methods');
+        }
+        $this->channel = new Channel($hostname, $opts);
+    }
+
+    /**
+     * @return string The URI of the endpoint.
+     */
+    public function getTarget()
+    {
+        return $this->channel->getTarget();
+    }
+
+    /**
+     * @param $try_to_connect bool
+     *
+     * @return int The grpc connectivity state
+     */
+    public function getConnectivityState($try_to_connect = false)
+    {
+        return $this->channel->getConnectivityState($try_to_connect);
+    }
+
+    /**
+     * @param $timeout in microseconds
+     *
+     * @return bool true if channel is ready
+     * @throw Exception if channel is in FATAL_ERROR state
+     */
+    public function waitForReady($timeout)
+    {
+        $new_state = $this->getConnectivityState(true);
+        if ($this->_checkConnectivityState($new_state)) {
+            return true;
+        }
+
+        $now = Timeval::now();
+        $delta = new Timeval($timeout);
+        $deadline = $now->add($delta);
+
+        while ($this->channel->watchConnectivityState($new_state, $deadline)) {
+            // state has changed before deadline
+            $new_state = $this->getConnectivityState();
+            if ($this->_checkConnectivityState($new_state)) {
+                return true;
+            }
+        }
+        // deadline has passed
+        $new_state = $this->getConnectivityState();
+
+        return $this->_checkConnectivityState($new_state);
+    }
+
+    private function _checkConnectivityState($new_state)
+    {
+        if ($new_state == \Grpc\CHANNEL_READY) {
+            return true;
+        }
+        if ($new_state == \Grpc\CHANNEL_FATAL_FAILURE) {
+            throw new \Exception('Failed to connect to server');
+        }
+
+        return false;
+    }
+
+    /**
+     * Close the communication channel associated with this stub.
+     */
+    public function close()
+    {
+        $this->channel->close();
+    }
+
+    /**
+     * constructs the auth uri for the jwt.
+     */
+    private function _get_jwt_aud_uri($method)
+    {
+        $last_slash_idx = strrpos($method, '/');
+        if ($last_slash_idx === false) {
+            throw new \InvalidArgumentException(
+                'service name must have a slash');
+        }
+        $service_name = substr($method, 0, $last_slash_idx);
+
+        return 'https://'.$this->hostname.$service_name;
+    }
+
+    /**
+     * validate and normalize the metadata array.
+     *
+     * @param $metadata The metadata map
+     *
+     * @return $metadata Validated and key-normalized metadata map
+     * @throw InvalidArgumentException if key contains invalid characters
+     */
+    private function _validate_and_normalize_metadata($metadata)
+    {
+        $metadata_copy = [];
+        foreach ($metadata as $key => $value) {
+            if (!preg_match('/^[A-Za-z\d_-]+$/', $key)) {
+                throw new \InvalidArgumentException(
+                    'Metadata keys must be nonempty strings containing only '.
+                    'alphanumeric characters, hyphens and underscores');
+            }
+            $metadata_copy[strtolower($key)] = $value;
+        }
+
+        return $metadata_copy;
+    }
+
+    /* This class is intended to be subclassed by generated code, so
+     * all functions begin with "_" to avoid name collisions. */
+
+    /**
+     * Call a remote method that takes a single argument and has a
+     * single output.
+     *
+     * @param string $method The name of the method to call
+     * @param $argument The argument to the method
+     * @param callable $deserialize A function that deserializes the response
+     * @param array    $metadata    A metadata map to send to the server
+     *
+     * @return SimpleSurfaceActiveCall The active call object
+     */
+    public function _simpleRequest($method,
+                                   $argument,
+                                   $deserialize,
+                                   $metadata = [],
+                                   $options = [])
+    {
+        $call = new UnaryCall($this->channel,
+                              $method,
+                              $deserialize,
+                              $options);
+        $jwt_aud_uri = $this->_get_jwt_aud_uri($method);
+        if (is_callable($this->update_metadata)) {
+            $metadata = call_user_func($this->update_metadata,
+                                        $metadata,
+                                        $jwt_aud_uri);
+        }
+        $metadata = $this->_validate_and_normalize_metadata(
+            $metadata);
+        $call->start($argument, $metadata, $options);
+
+        return $call;
+    }
+
+    /**
+     * Call a remote method that takes a stream of arguments and has a single
+     * output.
+     *
+     * @param string $method The name of the method to call
+     * @param $arguments An array or Traversable of arguments to stream to the
+     *     server
+     * @param callable $deserialize A function that deserializes the response
+     * @param array    $metadata    A metadata map to send to the server
+     *
+     * @return ClientStreamingSurfaceActiveCall The active call object
+     */
+    public function _clientStreamRequest($method,
+                                         callable $deserialize,
+                                         $metadata = [],
+                                         $options = [])
+    {
+        $call = new ClientStreamingCall($this->channel,
+                                        $method,
+                                        $deserialize,
+                                        $options);
+        $jwt_aud_uri = $this->_get_jwt_aud_uri($method);
+        if (is_callable($this->update_metadata)) {
+            $metadata = call_user_func($this->update_metadata,
+                                        $metadata,
+                                        $jwt_aud_uri);
+        }
+        $metadata = $this->_validate_and_normalize_metadata(
+            $metadata);
+        $call->start($metadata);
+
+        return $call;
+    }
+
+    /**
+     * Call a remote method that takes a single argument and returns a stream of
+     * responses.
+     *
+     * @param string $method The name of the method to call
+     * @param $argument The argument to the method
+     * @param callable $deserialize A function that deserializes the responses
+     * @param array    $metadata    A metadata map to send to the server
+     *
+     * @return ServerStreamingSurfaceActiveCall The active call object
+     */
+    public function _serverStreamRequest($method,
+                                         $argument,
+                                         callable $deserialize,
+                                         $metadata = [],
+                                         $options = [])
+    {
+        $call = new ServerStreamingCall($this->channel,
+                                        $method,
+                                        $deserialize,
+                                        $options);
+        $jwt_aud_uri = $this->_get_jwt_aud_uri($method);
+        if (is_callable($this->update_metadata)) {
+            $metadata = call_user_func($this->update_metadata,
+                                        $metadata,
+                                        $jwt_aud_uri);
+        }
+        $metadata = $this->_validate_and_normalize_metadata(
+            $metadata);
+        $call->start($argument, $metadata, $options);
+
+        return $call;
+    }
+
+    /**
+     * Call a remote method with messages streaming in both directions.
+     *
+     * @param string   $method      The name of the method to call
+     * @param callable $deserialize A function that deserializes the responses
+     * @param array    $metadata    A metadata map to send to the server
+     *
+     * @return BidiStreamingSurfaceActiveCall The active call object
+     */
+    public function _bidiRequest($method,
+                                 callable $deserialize,
+                                 $metadata = [],
+                                 $options = [])
+    {
+        $call = new BidiStreamingCall($this->channel,
+                                      $method,
+                                      $deserialize,
+                                      $options);
+        $jwt_aud_uri = $this->_get_jwt_aud_uri($method);
+        if (is_callable($this->update_metadata)) {
+            $metadata = call_user_func($this->update_metadata,
+                                        $metadata,
+                                        $jwt_aud_uri);
+        }
+        $metadata = $this->_validate_and_normalize_metadata(
+            $metadata);
+        $call->start($metadata);
+
+        return $call;
+    }
+}