Functional Version for Predis-PHP with tests

composer.json

@@ -27,6 +27,7 @@
         "twig/twig": "~2.0 || ~1.35",
         "symfony/yaml": "~3.3",
         "guzzlehttp/guzzle": "~5.3",
+        "predis/predis": "1.1.0",
         "guzzlehttp/psr7": "~1.4"
     },
     "conflict": {

src/Trace/Integrations/Redis.php

@@ -52,6 +52,7 @@ public static function load()
     /**
      * Trace Construct Options
      *
+     * @param $predis
      * @param  $params
      * @return array
      */
@@ -69,6 +70,7 @@ public static function handleConstruct($predis, $params)
     /**
      * Trace Set / Get Operations
      *
+     * @param $predis
      * @param  $key
      * @return array
      */

tests/integration/redis/composer.json

@@ -2,6 +2,7 @@
     "require": {
         "php": "^7.2",
         "opencensus/opencensus": "dev-master",
+        "predis/predis": "1.1.0",
         "ext-opencensus": "*",
         "ext-phpredis": "*"
     },

tests/integration/redis/tests/RedisTest.php

@@ -17,8 +17,11 @@
 
 namespace OpenCensus\Tests\Integration\Trace\Exporter;
 
+use OpenCensus\Trace\Tracer;
+use OpenCensus\Trace\Exporter\ExporterInterface;
 use OpenCensus\Trace\Integrations\Redis as RedisIntegration;
 use PHPUnit\Framework\TestCase;
+use Predis\Client;
 
 class RedisTest extends TestCase
 {
@@ -32,4 +35,37 @@ public static function setUpBeforeClass()
         self::$redisHost = getenv('REDIS_HOST') ?: '127.0.0.1';
         self::$redisPort = (int) (getenv('REDIS_PORT') ?: 6379);
     }
+
+    public function setUp()
+    {
+        if (!extension_loaded('opencensus')) {
+            $this->markTestSkipped('Please enable the opencensus extension.');
+        }
+        opencensus_trace_clear();
+        $exporter = $this->prophesize(ExporterInterface::class);
+        $this->tracer = Tracer::start($exporter->reveal(), [
+            'skipReporting' => true
+        ]);
+    }
+
+    private function getSpans()
+    {
+        $this->tracer->onExit();
+        return $this->tracer->tracer()->spans();
+    }
+
+    public function testAddGet()
+    {
+        $client = new Client([
+            'host' => self::$redisHost,
+            'port'   => self::$redisPort
+        ]);
+
+        $client->set('foo', 'bar');
+        $value = $client->get('foo');
+        $this->assertEquals('bar', $value);
+
+        $spans = $this->getSpans();
+        $this->assertCount(4, $spans);
+    }
 }