php: add watchForReady method

src/php/lib/Grpc/BaseStub.php

@@ -82,6 +82,40 @@ class BaseStub {
     return $this->channel->getConnectivityState($try_to_connect);
   }
 
+  /**
+   * @param $timeout in microseconds
+   * @return bool true if channel is ready
+   */
+  public function watchForReady($timeout) {
+    $new_state = $this->getConnectivityState(true);
+    if ($this->_checkConnectivityState($new_state)) {
+      return true;
+    }
+
+    $now = Timeval::now();
+    $delta = new Timeval($timeout);
+    $deadline = $now->add($delta);
+
+    if (!$this->channel->watchConnectivityState($new_state, $deadline)) {
+      return false;
+    }
+    $new_state = $this->getConnectivityState();
+    if ($this->_checkConnectivityState($new_state)) {
+      return true;
+    }
+    return false;
+  }
+
+  private function _checkConnectivityState($new_state) {
+    if ($new_state == Grpc\CHANNEL_READY) {
+      return true;
+    }
+    if ($new_state == Grpc\CHANNEL_FATAL_ERROR) {
+      throw new Exception('Failed to connect to server');
+    }
+    return false;
+  }
+
   /**
    * Close the communication channel associated with this stub
    */

src/php/tests/unit_tests/EndToEndTest.php

@@ -175,7 +175,7 @@ class EndToEndTest extends PHPUnit_Framework_TestCase{
     $this->assertTrue($idle_state == Grpc\CHANNEL_IDLE);
 
     $now = Grpc\Timeval::now();
-    $delta = new Grpc\Timeval(100000);
+    $delta = new Grpc\Timeval(3000000); // should finish well before
     $deadline = $now->add($delta);
 
     $this->assertTrue($this->channel->watchConnectivityState(
@@ -184,4 +184,19 @@ class EndToEndTest extends PHPUnit_Framework_TestCase{
     $new_state = $this->channel->getConnectivityState();
     $this->assertTrue($idle_state != $new_state);
   }
+
+  public function testWatchConnectivityStateDoNothing() {
+    $idle_state = $this->channel->getConnectivityState();
+    $this->assertTrue($idle_state == Grpc\CHANNEL_IDLE);
+
+    $now = Grpc\Timeval::now();
+    $delta = new Grpc\Timeval(100000);
+    $deadline = $now->add($delta);
+
+    $this->assertFalse($this->channel->watchConnectivityState(
+        $idle_state, $deadline));
+
+    $new_state = $this->channel->getConnectivityState();
+    $this->assertTrue($new_state == Grpc\CHANNEL_IDLE);
+  }
 }