Add integration test against grpc master with interceptor support

src/Trace/Integrations/Grpc/TraceInterceptor.php

@@ -0,0 +1,163 @@
+<?php
+/**
+ * Copyright 2018 OpenCensus Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+namespace OpenCensus\Trace\Integrations\Grpc;
+
+use Grpc\Interceptor;
+use OpenCensus\Trace\Propagator\PropagatorInterface;
+use OpenCensus\Trace\Propagator\GrpcMetadataPropagator;
+use OpenCensus\Trace\Span;
+use OpenCensus\Trace\Tracer;
+
+/**
+ * This interceptor creates a Span for each type of gRPC call and injects a
+ * metadata attribute to propagate SpanContext to downstream services.
+ *
+ * Example:
+ * ```
+ * $interceptor = new TraceInterceptor();
+ * $channel = new Grpc\Channel('127.0.0.1:1234');
+ * $channel = Grpc\Interceptor::intercept($channel, $interceptor);
+ * $client = new MyGrpcClient('127.0.0.1:1234', $channel);
+ * ```
+ */
+class TraceInterceptor extends Interceptor
+{
+    /* @var PropagatorInterface */
+    private $propagator;
+
+    /**
+     * Create a new TraceInterceptor.
+     *
+     * @param PropagatorInterface $propagator The
+     */
+    public function __construct($propagator = null)
+    {
+        $this->propagator = $propagator ?: new GrpcMetadataPropagator();
+    }
+
+    /**
+     * This interceptor is for simple unary requests.
+     *
+     * @param string $method The name of the method to call
+     * @param mixed $argument The argument to the method
+     * @param array $metadata A metadata map to send to the server (optional)
+     * @param array $options An array of options (optional)
+     * @param callable $continuation The next interceptor to call
+     */
+    public function interceptUnaryUnary(
+        $method,
+        $argument,
+        array $metadata,
+        array $options,
+        $continuation
+    ) {
+        $spanOptions = [
+            'name' => 'grpc/simpleRequest',
+            'attributes' => [
+                'method' => $method
+            ],
+            'kind' => Span::KIND_CLIENT
+        ];
+        $metadata = $this->injectMetadata($metadata);
+
+        return Tracer::inSpan($spanOptions, $continuation, [$method, $argument, $metadata, $options]);
+    }
+
+    /**
+     * This interceptor is for client streaming requests.
+     *
+     * @param string $method The name of the method to call
+     * @param array $metadata A metadata map to send to the server (optional)
+     * @param array $options An array of options (optional)
+     * @param callable $continuation The next interceptor to call
+     */
+    public function interceptStreamUnary(
+        $method,
+        array $metadata,
+        array $options,
+        $continuation
+    ) {
+        $spanOptions = [
+            'name' => 'grpc/clientStreamRequest',
+            'attributes' => [
+                'method' => $method
+            ],
+            'kind' => Span::KIND_CLIENT
+        ];
+        $metadata = $this->injectMetadata($metadata);
+        return Tracer::inSpan($spanOptions, $continuation, [$method, $metadata, $options]);
+    }
+
+    /**
+     * This interceptor is for server streaming requests.
+     *
+     * @param string $method The name of the method to call
+     * @param mixed $argument The argument to the method
+     * @param array $metadata A metadata map to send to the server (optional)
+     * @param array $options An array of options (optional)
+     * @param callable $continuation The next interceptor to call
+     */
+    public function interceptUnaryStream(
+        $method,
+        $argument,
+        array $metadata,
+        array $options,
+        $continuation
+    ) {
+        $spanOptions = [
+            'name' => 'grpc/serverStreamRequest',
+            'attributes' => [
+                'method' => $method
+            ],
+            'kind' => Span::KIND_CLIENT
+        ];
+        $metadata = $this->injectMetadata($metadata);
+        return Tracer::inSpan($spanOptions, $continuation, [$method, $argument, $metadata, $options]);
+    }
+
+    /**
+     * This interceptor is for server streaming requests.
+     *
+     * @param string $method The name of the method to call
+     * @param array $metadata A metadata map to send to the server (optional)
+     * @param array $options An array of options (optional)
+     * @param callable $continuation The next interceptor to call
+     */
+    public function interceptStreamStream(
+        $method,
+        array $metadata,
+        array $options,
+        $continuation
+    ) {
+        $spanOptions = [
+            'name' => 'grpc/bidiRequest',
+            'attributes' => [
+                'method' => $method
+            ],
+            'kind' => Span::KIND_CLIENT
+        ];
+        $metadata = $this->injectMetadata($metadata);
+        return Tracer::inSpan($spanOptions, $continuation, [$method, $metadata, $options]);
+    }
+
+    private function injectMetadata(array $metadata)
+    {
+        $context = Tracer::spanContext();
+        return $this->propagator->inject($context, $metadata);
+    }
+}

src/Trace/Propagator/GrpcMetadataPropagator.php

@@ -75,7 +75,7 @@ public function extract($metadata)
      */
     public function inject(SpanContext $context, $metadata)
     {
-        $metadata[$this->key] = $this->formatter->serialize($context);
+        $metadata[$this->key] = [$this->formatter->serialize($context)];
         return $metadata;
     }
 

tests/integration/grpc/composer.json

@@ -0,0 +1,22 @@
+{
+    "require": {
+        "php": "^7.2",
+        "opencensus/opencensus": "dev-master",
+        "grpc/grpc": "dev-master",
+        "ext-opencensus": "*",
+        "ext-grpc": "*"
+    },
+    "require-dev": {
+        "phpunit/phpunit": "^7.0"
+    },
+    "repositories": {
+        "opencensus": {
+            "type": "git",
+            "url": "https://github.com/census-instrumentation/opencensus-php"
+        },
+        "grpc": {
+            "type": "git",
+            "url": "https://github.com/grpc/grpc"
+        }
+    }
+}

tests/integration/grpc/phpunit.xml.dist

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<phpunit bootstrap="./vendor/autoload.php" colors="true">
+  <testsuites>
+    <testsuite>
+      <directory>tests</directory>
+    </testsuite>
+  </testsuites>
+  <filter>
+    <whitelist>
+      <directory suffix=".php">src</directory>
+    </whitelist>
+  </filter>
+</phpunit>

tests/integration/grpc/test.sh

@@ -0,0 +1,27 @@
+#!/bin/bash
+# Copyright 2018 OpenCensus Authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+set -e
+
+pushd $(dirname ${BASH_SOURCE[0]})
+source ../setup_test_repo.sh
+
+sed -i "s|dev-master|dev-${BRANCH}|" composer.json
+sed -i "s|https://github.com/census-instrumentation/opencensus-php|${REPO}|" composer.json
+composer install -n --prefer-dist
+
+vendor/bin/phpunit
+
+popd