Merge pull request #4394 from stanley-cheung/php_creds_plugin_api

PHP: metadata plugin based auth API

9 files changed, 350 insertions, 76 deletions

diff --git a/src/php/ext/grpc/call.c b/src/php/ext/grpc/call.c
index 3b99de7538..7ba14a38d8 100644
--- a/src/php/ext/grpc/call.c
+++ b/src/php/ext/grpc/call.c
@@ -42,13 +42,13 @@
 #include <ext/standard/info.h>
 #include <ext/spl/spl_exceptions.h>
 #include "php_grpc.h"
+#include "call_credentials.h"
 
 #include <zend_exceptions.h>
 #include <zend_hash.h>
 
 #include <stdbool.h>
 
-#include <grpc/support/log.h>
 #include <grpc/support/alloc.h>
 #include <grpc/grpc.h>
 
@@ -515,11 +515,41 @@ PHP_METHOD(Call, cancel) {
   grpc_call_cancel(call->wrapped, NULL);
 }
 
+/**
+ * Set the CallCredentials for this call.
+ * @param CallCredentials creds_obj The CallCredentials object
+ * @param int The error code
+ */
+PHP_METHOD(Call, setCredentials) {
+  zval *creds_obj;
+
+  /* "O" == 1 Object */
+  if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "O", &creds_obj,
+                            grpc_ce_call_credentials) == FAILURE) {
+    zend_throw_exception(spl_ce_InvalidArgumentException,
+                         "setCredentials expects 1 CallCredentials",
+                         1 TSRMLS_CC);
+    return;
+  }
+
+  wrapped_grpc_call_credentials *creds =
+      (wrapped_grpc_call_credentials *)zend_object_store_get_object(
+          creds_obj TSRMLS_CC);
+
+  wrapped_grpc_call *call =
+      (wrapped_grpc_call *)zend_object_store_get_object(getThis() TSRMLS_CC);
+
+  grpc_call_error error = GRPC_CALL_ERROR;
+  error = grpc_call_set_credentials(call->wrapped, creds->wrapped);
+  RETURN_LONG(error);
+}
+
 static zend_function_entry call_methods[] = {
     PHP_ME(Call, __construct, NULL, ZEND_ACC_PUBLIC | ZEND_ACC_CTOR)
     PHP_ME(Call, startBatch, NULL, ZEND_ACC_PUBLIC)
     PHP_ME(Call, getPeer, NULL, ZEND_ACC_PUBLIC)
     PHP_ME(Call, cancel, NULL, ZEND_ACC_PUBLIC)
+    PHP_ME(Call, setCredentials, NULL, ZEND_ACC_PUBLIC)
     PHP_FE_END};
 
 void grpc_init_call(TSRMLS_D) {
diff --git a/src/php/ext/grpc/call.h b/src/php/ext/grpc/call.h
index f3ef89dc97..73efadae35 100644
--- a/src/php/ext/grpc/call.h
+++ b/src/php/ext/grpc/call.h
@@ -66,4 +66,8 @@ zval *grpc_php_wrap_call(grpc_call *wrapped, bool owned);
  * call metadata */
 zval *grpc_parse_metadata_array(grpc_metadata_array *metadata_array);
 
+/* Populates a grpc_metadata_array with the data in a PHP array object.
+   Returns true on success and false on failure */
+bool create_metadata_array(zval *array, grpc_metadata_array *metadata);
+
 #endif /* NET_GRPC_PHP_GRPC_CHANNEL_H_ */
diff --git a/src/php/ext/grpc/call_credentials.c b/src/php/ext/grpc/call_credentials.c
index 17f167befb..285c4e7c85 100644
--- a/src/php/ext/grpc/call_credentials.c
+++ b/src/php/ext/grpc/call_credentials.c
@@ -43,6 +43,7 @@
 #include <ext/standard/info.h>
 #include <ext/spl/spl_exceptions.h>
 #include "php_grpc.h"
+#include "call.h"
 
 #include <zend_exceptions.h>
 #include <zend_hash.h>
@@ -103,7 +104,7 @@ PHP_METHOD(CallCredentials, createComposite) {
   zval *cred1_obj;
   zval *cred2_obj;
 
-  /* "OO" == 3 Objects */
+  /* "OO" == 2 Objects */
   if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "OO", &cred1_obj,
                             grpc_ce_call_credentials, &cred2_obj,
                             grpc_ce_call_credentials) == FAILURE) {
@@ -125,9 +126,107 @@ PHP_METHOD(CallCredentials, createComposite) {
   RETURN_DESTROY_ZVAL(creds_object);
 }
 
+/**
+ * Create a call credentials object from the plugin API
+ * @param function callback The callback function
+ * @return CallCredentials The new call credentials object
+ */
+PHP_METHOD(CallCredentials, createFromPlugin) {
+  zend_fcall_info *fci;
+  zend_fcall_info_cache *fci_cache;
+
+  fci = (zend_fcall_info *)emalloc(sizeof(zend_fcall_info));
+  fci_cache = (zend_fcall_info_cache *)emalloc(sizeof(zend_fcall_info_cache));
+  memset(fci, 0, sizeof(zend_fcall_info));
+  memset(fci_cache, 0, sizeof(zend_fcall_info_cache));
+
+  /* "f" == 1 function */
+  if (zend_parse_parameters(ZEND_NUM_ARGS(), "f", fci,
+                            fci_cache,
+                            fci->params,
+                            fci->param_count) == FAILURE) {
+    zend_throw_exception(spl_ce_InvalidArgumentException,
+                         "createFromPlugin expects 1 callback",
+                         1 TSRMLS_CC);
+    return;
+  }
+
+  plugin_state *state;
+  state = (plugin_state *)emalloc(sizeof(plugin_state));
+  memset(state, 0, sizeof(plugin_state));
+
+  /* save the user provided PHP callback function */
+  state->fci = fci;
+  state->fci_cache = fci_cache;
+
+  grpc_metadata_credentials_plugin plugin;
+  plugin.get_metadata = plugin_get_metadata;
+  plugin.destroy = plugin_destroy_state;
+  plugin.state = (void *)state;
+  plugin.type = "";
+
+  grpc_call_credentials *creds = grpc_metadata_credentials_create_from_plugin(
+      plugin, NULL);
+  zval *creds_object = grpc_php_wrap_call_credentials(creds);
+  RETURN_DESTROY_ZVAL(creds_object);
+}
+
+/* Callback function for plugin creds API */
+void plugin_get_metadata(void *ptr, grpc_auth_metadata_context context,
+                         grpc_credentials_plugin_metadata_cb cb,
+                         void *user_data) {
+  plugin_state *state = (plugin_state *)ptr;
+
+  /* prepare to call the user callback function with info from the
+   * grpc_auth_metadata_context */
+  zval **params[1];
+  zval *arg;
+  zval *retval;
+  MAKE_STD_ZVAL(arg);
+  object_init(arg);
+  add_property_string(arg, "service_url", context.service_url, true);
+  add_property_string(arg, "method_name", context.method_name, true);
+  params[0] = &arg;
+  state->fci->param_count = 1;
+  state->fci->params = params;
+  state->fci->retval_ptr_ptr = &retval;
+
+  /* call the user callback function */
+  zend_call_function(state->fci, state->fci_cache);
+
+  if (Z_TYPE_P(retval) != IS_ARRAY) {
+    zend_throw_exception(spl_ce_InvalidArgumentException,
+                         "plugin callback must return metadata array",
+                         1 TSRMLS_CC);
+  }
+
+  grpc_metadata_array metadata;
+  if (!create_metadata_array(retval, &metadata)) {
+    zend_throw_exception(spl_ce_InvalidArgumentException,
+                         "invalid metadata", 1 TSRMLS_CC);
+    grpc_metadata_array_destroy(&metadata);
+  }
+
+  /* TODO: handle error */
+  grpc_status_code code = GRPC_STATUS_OK;
+
+  /* Pass control back to core */
+  cb(user_data, metadata.metadata, metadata.count, code, NULL);
+}
+
+/* Cleanup function for plugin creds API */
+void plugin_destroy_state(void *ptr) {
+  plugin_state *state = (plugin_state *)ptr;
+  efree(state->fci);
+  efree(state->fci_cache);
+  efree(state);
+}
+
 static zend_function_entry call_credentials_methods[] = {
   PHP_ME(CallCredentials, createComposite, NULL,
          ZEND_ACC_PUBLIC | ZEND_ACC_STATIC)
+  PHP_ME(CallCredentials, createFromPlugin, NULL,
+         ZEND_ACC_PUBLIC | ZEND_ACC_STATIC)
   PHP_FE_END};
 
 void grpc_init_call_credentials(TSRMLS_D) {
diff --git a/src/php/ext/grpc/call_credentials.h b/src/php/ext/grpc/call_credentials.h
index 8f35ac68bc..d2f6a92449 100755
--- a/src/php/ext/grpc/call_credentials.h
+++ b/src/php/ext/grpc/call_credentials.h
@@ -57,6 +57,20 @@ typedef struct wrapped_grpc_call_credentials {
   grpc_call_credentials *wrapped;
 } wrapped_grpc_call_credentials;
 
+/* Struct to hold callback function for plugin creds API */
+typedef struct plugin_state {
+  zend_fcall_info *fci;
+  zend_fcall_info_cache *fci_cache;
+} plugin_state;
+
+/* Callback function for plugin creds API */
+void plugin_get_metadata(void *state, grpc_auth_metadata_context context,
+                         grpc_credentials_plugin_metadata_cb cb,
+                         void *user_data);
+
+/* Cleanup function for plugin creds API */
+void plugin_destroy_state(void *ptr);
+
 /* Initializes the CallCredentials PHP class */
 void grpc_init_call_credentials(TSRMLS_D);
 
diff --git a/src/php/lib/Grpc/AbstractCall.php b/src/php/lib/Grpc/AbstractCall.php
index 53849d51fc..c80cf4464e 100644
--- a/src/php/lib/Grpc/AbstractCall.php
+++ b/src/php/lib/Grpc/AbstractCall.php
@@ -43,19 +43,20 @@ abstract class AbstractCall
     /**
      * Create a new Call wrapper object.
      *
-     * @param Channel         $channel     The channel to communicate on
-     * @param string          $method      The method to call on the
-     *                                     remote server
-     * @param callback        $deserialize A callback function to deserialize
-     *                                     the response
-     * @param (optional) long $timeout     Timeout in microseconds
+     * @param Channel  $channel     The channel to communicate on
+     * @param string   $method      The method to call on the
+     *                              remote server
+     * @param callback $deserialize A callback function to deserialize
+     *                              the response
+     * @param array    $options     Call options (optional)
      */
     public function __construct(Channel $channel,
                                 $method,
                                 $deserialize,
-                                $timeout = false)
+                                $options = [])
     {
-        if ($timeout) {
+        if (isset($options['timeout']) &&
+            is_numeric($timeout = $options['timeout'])) {
             $now = Timeval::now();
             $delta = new Timeval($timeout);
             $deadline = $now->add($delta);
@@ -65,6 +66,13 @@ abstract class AbstractCall
         $this->call = new Call($channel, $method, $deadline);
         $this->deserialize = $deserialize;
         $this->metadata = null;
+        if (isset($options['call_credentials_callback']) &&
+            is_callable($call_credentials_callback =
+                        $options['call_credentials_callback'])) {
+            $call_credentials = CallCredentials::createFromPlugin(
+                $call_credentials_callback);
+            $this->call->setCredentials($call_credentials);
+        }
     }
 
     /**
diff --git a/src/php/lib/Grpc/BaseStub.php b/src/php/lib/Grpc/BaseStub.php
index 7b2627f516..8e9dedf73b 100755
--- a/src/php/lib/Grpc/BaseStub.php
+++ b/src/php/lib/Grpc/BaseStub.php
@@ -159,25 +159,6 @@ class BaseStub
     }
 
     /**
-     * extract $timeout from $metadata.
-     *
-     * @param $metadata The metadata map
-     *
-     * @return list($metadata_copy, $timeout)
-     */
-    private function _extract_timeout_from_metadata($metadata)
-    {
-        $timeout = false;
-        $metadata_copy = $metadata;
-        if (isset($metadata['timeout'])) {
-            $timeout = $metadata['timeout'];
-            unset($metadata_copy['timeout']);
-        }
-
-        return [$metadata_copy, $timeout];
-    }
-
-    /**
      * validate and normalize the metadata array.
      *
      * @param $metadata The metadata map
@@ -220,21 +201,19 @@ class BaseStub
                                    $metadata = [],
                                    $options = [])
     {
-        list($actual_metadata, $timeout) =
-            $this->_extract_timeout_from_metadata($metadata);
         $call = new UnaryCall($this->channel,
                               $method,
                               $deserialize,
-                              $timeout);
+                              $options);
         $jwt_aud_uri = $this->_get_jwt_aud_uri($method);
         if (is_callable($this->update_metadata)) {
-            $actual_metadata = call_user_func($this->update_metadata,
-                                        $actual_metadata,
+            $metadata = call_user_func($this->update_metadata,
+                                        $metadata,
                                         $jwt_aud_uri);
         }
-        $actual_metadata = $this->_validate_and_normalize_metadata(
-            $actual_metadata);
-        $call->start($argument, $actual_metadata, $options);
+        $metadata = $this->_validate_and_normalize_metadata(
+            $metadata);
+        $call->start($argument, $metadata, $options);
 
         return $call;
     }
@@ -253,23 +232,22 @@ class BaseStub
      */
     public function _clientStreamRequest($method,
                                          callable $deserialize,
-                                         $metadata = [])
+                                         $metadata = [],
+                                         $options = [])
     {
-        list($actual_metadata, $timeout) =
-            $this->_extract_timeout_from_metadata($metadata);
         $call = new ClientStreamingCall($this->channel,
                                         $method,
                                         $deserialize,
-                                        $timeout);
+                                        $options);
         $jwt_aud_uri = $this->_get_jwt_aud_uri($method);
         if (is_callable($this->update_metadata)) {
-            $actual_metadata = call_user_func($this->update_metadata,
-                                        $actual_metadata,
+            $metadata = call_user_func($this->update_metadata,
+                                        $metadata,
                                         $jwt_aud_uri);
         }
-        $actual_metadata = $this->_validate_and_normalize_metadata(
-            $actual_metadata);
-        $call->start($actual_metadata);
+        $metadata = $this->_validate_and_normalize_metadata(
+            $metadata);
+        $call->start($metadata);
 
         return $call;
     }
@@ -291,21 +269,19 @@ class BaseStub
                                          $metadata = [],
                                          $options = [])
     {
-        list($actual_metadata, $timeout) =
-            $this->_extract_timeout_from_metadata($metadata);
         $call = new ServerStreamingCall($this->channel,
                                         $method,
                                         $deserialize,
-                                        $timeout);
+                                        $options);
         $jwt_aud_uri = $this->_get_jwt_aud_uri($method);
         if (is_callable($this->update_metadata)) {
-            $actual_metadata = call_user_func($this->update_metadata,
-                                        $actual_metadata,
+            $metadata = call_user_func($this->update_metadata,
+                                        $metadata,
                                         $jwt_aud_uri);
         }
-        $actual_metadata = $this->_validate_and_normalize_metadata(
-            $actual_metadata);
-        $call->start($argument, $actual_metadata, $options);
+        $metadata = $this->_validate_and_normalize_metadata(
+            $metadata);
+        $call->start($argument, $metadata, $options);
 
         return $call;
     }
@@ -321,23 +297,22 @@ class BaseStub
      */
     public function _bidiRequest($method,
                                  callable $deserialize,
-                                 $metadata = [])
+                                 $metadata = [],
+                                 $options = [])
     {
-        list($actual_metadata, $timeout) =
-            $this->_extract_timeout_from_metadata($metadata);
         $call = new BidiStreamingCall($this->channel,
                                       $method,
                                       $deserialize,
-                                      $timeout);
+                                      $options);
         $jwt_aud_uri = $this->_get_jwt_aud_uri($method);
         if (is_callable($this->update_metadata)) {
-            $actual_metadata = call_user_func($this->update_metadata,
-                                        $actual_metadata,
+            $metadata = call_user_func($this->update_metadata,
+                                        $metadata,
                                         $jwt_aud_uri);
         }
-        $actual_metadata = $this->_validate_and_normalize_metadata(
-            $actual_metadata);
-        $call->start($actual_metadata);
+        $metadata = $this->_validate_and_normalize_metadata(
+            $metadata);
+        $call->start($metadata);
 
         return $call;
     }
diff --git a/src/php/tests/generated_code/AbstractGeneratedCodeTest.php b/src/php/tests/generated_code/AbstractGeneratedCodeTest.php
index 4a0bd6a1f1..aa6906192f 100644
--- a/src/php/tests/generated_code/AbstractGeneratedCodeTest.php
+++ b/src/php/tests/generated_code/AbstractGeneratedCodeTest.php
@@ -41,7 +41,6 @@ abstract class AbstractGeneratedCodeTest extends PHPUnit_Framework_TestCase
      * running on $GRPC_TEST_HOST.
      */
     protected static $client;
-    protected static $timeout;
 
     public function testWaitForNotReady()
     {
@@ -93,7 +92,7 @@ abstract class AbstractGeneratedCodeTest extends PHPUnit_Framework_TestCase
     public function testTimeout()
     {
         $div_arg = new math\DivArgs();
-        $call = self::$client->Div($div_arg, ['timeout' => 100]);
+        $call = self::$client->Div($div_arg, [], ['timeout' => 100]);
         list($response, $status) = $call->wait();
         $this->assertSame(\Grpc\STATUS_DEADLINE_EXCEEDED, $status->code);
     }
diff --git a/src/php/tests/interop/interop_client.php b/src/php/tests/interop/interop_client.php
index 9aab5c966c..ee604a387c 100755
--- a/src/php/tests/interop/interop_client.php
+++ b/src/php/tests/interop/interop_client.php
@@ -84,7 +84,7 @@ function largeUnary($stub)
  * @param $fillOauthScope boolean whether to fill result with oauth scope
  */
 function performLargeUnary($stub, $fillUsername = false, $fillOauthScope = false,
-                           $metadata = [])
+                           $callback = false)
 {
     $request_len = 271828;
     $response_len = 314159;
@@ -99,7 +99,12 @@ function performLargeUnary($stub, $fillUsername = false, $fillOauthScope = false
     $request->setFillUsername($fillUsername);
     $request->setFillOauthScope($fillOauthScope);
 
-    list($result, $status) = $stub->UnaryCall($request, $metadata)->wait();
+    $options = false;
+    if ($callback) {
+        $options['call_credentials_callback'] = $callback;
+    }
+
+    list($result, $status) = $stub->UnaryCall($request, [], $options)->wait();
     hardAssert($status->code === Grpc\STATUS_OK, 'Call did not complete successfully');
     hardAssert($result !== null, 'Call returned a null response');
     $payload = $result->getPayload();
@@ -186,6 +191,15 @@ function oauth2AuthToken($stub, $args)
              'invalid email returned');
 }
 
+function updateAuthMetadataCallback($context)
+{
+    $authUri = $context->service_url;
+    $methodName = $context->method_name;
+    $auth_credentials = ApplicationDefaultCredentials::getCredentials();
+
+    return $auth_credentials->updateMetadata($metadata = [], $authUri);
+}
+
 /**
  * Run the per_rpc_creds auth test.
  *
@@ -197,15 +211,9 @@ function perRpcCreds($stub, $args)
     $jsonKey = json_decode(
         file_get_contents(getenv(CredentialsLoader::ENV_VAR)),
         true);
-    $auth_credentials = ApplicationDefaultCredentials::getCredentials(
-        $args['oauth_scope']
-    );
-    $token = $auth_credentials->fetchAuthToken();
-    $metadata = [CredentialsLoader::AUTH_METADATA_KEY => [sprintf('%s %s',
-                          $token['token_type'],
-                          $token['access_token'])]];
+
     $result = performLargeUnary($stub, $fillUsername = true, $fillOauthScope = true,
-                              $metadata);
+                                'updateAuthMetadataCallback');
     hardAssert($result->getUsername() == $jsonKey['client_email'],
              'invalid email returned');
 }
@@ -363,7 +371,7 @@ function cancelAfterFirstResponse($stub)
 
 function timeoutOnSleepingServer($stub)
 {
-    $call = $stub->FullDuplexCall(['timeout' => 1000]);
+    $call = $stub->FullDuplexCall([], ['timeout' => 1000]);
     $request = new grpc\testing\StreamingOutputCallRequest();
     $request->setResponseType(grpc\testing\PayloadType::COMPRESSABLE);
     $response_parameters = new grpc\testing\ResponseParameters();
diff --git a/src/php/tests/unit_tests/CallCredentialsTest.php b/src/php/tests/unit_tests/CallCredentialsTest.php
new file mode 100644
index 0000000000..0918412781
--- /dev/null
+++ b/src/php/tests/unit_tests/CallCredentialsTest.php
@@ -0,0 +1,137 @@
+<?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.
+ *
+ */
+
+class CallCredentialsTest extends PHPUnit_Framework_TestCase
+{
+    public function setUp()
+    {
+        $credentials = Grpc\ChannelCredentials::createSsl(
+            file_get_contents(dirname(__FILE__).'/../data/ca.pem'));
+        $call_credentials = Grpc\CallCredentials::createFromPlugin(
+            array($this, 'callbackFunc'));
+        $credentials = Grpc\ChannelCredentials::createComposite(
+            $credentials,
+            $call_credentials
+        );
+        $server_credentials = Grpc\ServerCredentials::createSsl(
+            null,
+            file_get_contents(dirname(__FILE__).'/../data/server1.key'),
+            file_get_contents(dirname(__FILE__).'/../data/server1.pem'));
+        $this->server = new Grpc\Server();
+        $this->port = $this->server->addSecureHttp2Port('0.0.0.0:0',
+                                              $server_credentials);
+        $this->server->start();
+        $this->host_override = 'foo.test.google.fr';
+        $this->channel = new Grpc\Channel(
+            'localhost:'.$this->port,
+            [
+            'grpc.ssl_target_name_override' => $this->host_override,
+            'grpc.default_authority' => $this->host_override,
+            'credentials' => $credentials,
+            ]
+        );
+    }
+
+    public function tearDown()
+    {
+        unset($this->channel);
+        unset($this->server);
+    }
+
+    public function callbackFunc($context)
+    {
+        $this->assertTrue(is_string($context->service_url));
+        $this->assertTrue(is_string($context->method_name));
+
+        return ['k1' => ['v1'], 'k2' => ['v2']];
+    }
+
+    public function testCreateFromPlugin()
+    {
+        $deadline = Grpc\Timeval::infFuture();
+        $status_text = 'xyz';
+        $call = new Grpc\Call($this->channel,
+                              '/abc/dummy_method',
+                              $deadline,
+                              $this->host_override);
+
+        $event = $call->startBatch([
+            Grpc\OP_SEND_INITIAL_METADATA => [],
+            Grpc\OP_SEND_CLOSE_FROM_CLIENT => true,
+        ]);
+
+        $this->assertTrue($event->send_metadata);
+        $this->assertTrue($event->send_close);
+
+        $event = $this->server->requestCall();
+
+        $this->assertTrue(is_array($event->metadata));
+        $metadata = $event->metadata;
+        $this->assertTrue(array_key_exists('k1', $metadata));
+        $this->assertTrue(array_key_exists('k2', $metadata));
+        $this->assertSame($metadata['k1'], ['v1']);
+        $this->assertSame($metadata['k2'], ['v2']);
+
+        $this->assertSame('/abc/dummy_method', $event->method);
+        $server_call = $event->call;
+
+        $event = $server_call->startBatch([
+            Grpc\OP_SEND_INITIAL_METADATA => [],
+            Grpc\OP_SEND_STATUS_FROM_SERVER => [
+                'metadata' => [],
+                'code' => Grpc\STATUS_OK,
+                'details' => $status_text,
+            ],
+            Grpc\OP_RECV_CLOSE_ON_SERVER => true,
+        ]);
+
+        $this->assertTrue($event->send_metadata);
+        $this->assertTrue($event->send_status);
+        $this->assertFalse($event->cancelled);
+
+        $event = $call->startBatch([
+            Grpc\OP_RECV_INITIAL_METADATA => true,
+            Grpc\OP_RECV_STATUS_ON_CLIENT => true,
+        ]);
+
+        $this->assertSame([], $event->metadata);
+        $status = $event->status;
+        $this->assertSame([], $status->metadata);
+        $this->assertSame(Grpc\STATUS_OK, $status->code);
+        $this->assertSame($status_text, $status->details);
+
+        unset($call);
+        unset($server_call);
+    }
+}