1 files changed, 45 insertions, 0 deletions
diff --git a/src/php/lib/Grpc/BaseStub.php b/src/php/lib/Grpc/BaseStub.php
index a0c677908c..9d6a77b855 100755
--- a/src/php/lib/Grpc/BaseStub.php
+++ b/src/php/lib/Grpc/BaseStub.php
@@ -75,6 +75,51 @@ class BaseStub {
   }
 
   /**
+   * @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_ERROR) {
+      throw new Exception('Failed to connect to server');
+    }
+    return false;
+  }
+
+  /**
    * Close the communication channel associated with this stub
    */
   public function close() {