PHPLIB-351: Update logic for identifying resumable errors

Skip redundant error message checks, since their codes do not overlap with the three errors specifically excluded by the spec and all other server errors are resumable.

Deprecate the unused class constant, which can be removed in 2.0 (PHPLIB-360).

src/ChangeStream.php

@@ -19,8 +19,9 @@ namespace MongoDB;
 
 use MongoDB\BSON\Serializable;
 use MongoDB\Driver\Cursor;
-use MongoDB\Driver\Exception\ConnectionTimeoutException;
+use MongoDB\Driver\Exception\ConnectionException;
 use MongoDB\Driver\Exception\RuntimeException;
+use MongoDB\Driver\Exception\ServerException;
 use MongoDB\Exception\InvalidArgumentException;
 use MongoDB\Exception\ResumeTokenException;
 use IteratorIterator;
@@ -35,14 +36,22 @@ use Iterator;
  */
 class ChangeStream implements Iterator
 {
+    /**
+     * @deprecated 1.4
+     * @todo Remove this in 2.0 (see: PHPLIB-360)
+     */
+    const CURSOR_NOT_FOUND = 43;
+
+    private static $errorCodeCappedPositionLost = 136;
+    private static $errorCodeInterrupted = 11601;
+    private static $errorCodeCursorKilled = 237;
+
     private $resumeToken;
     private $resumeCallable;
     private $csIt;
     private $key = 0;
     private $hasAdvanced = false;
 
-    const CURSOR_NOT_FOUND = 43;
-
     /**
      * Constructor.
      *
@@ -91,7 +100,6 @@ class ChangeStream implements Iterator
      */
     public function next()
     {
-        $resumable = false;
         try {
             $this->csIt->next();
             if ($this->valid()) {
@@ -111,18 +119,9 @@ class ChangeStream implements Iterator
                 $this->resumeCallable = null;
             }
         } catch (RuntimeException $e) {
-            if (strpos($e->getMessage(), "not master") !== false) {
-                $resumable = true;
+            if ($this->isResumableError($e)) {
+                $this->resume();
             }
-            if ($e->getCode() === self::CURSOR_NOT_FOUND) {
-                $resumable = true;
-            }
-            if ($e instanceof ConnectionTimeoutException) {
-                $resumable = true;
-            }
-        }
-        if ($resumable) {
-            $this->resume();
         }
     }
 
@@ -132,7 +131,6 @@ class ChangeStream implements Iterator
      */
     public function rewind()
     {
-        $resumable = false;
         try {
             $this->csIt->rewind();
             if ($this->valid()) {
@@ -144,18 +142,9 @@ class ChangeStream implements Iterator
                 $this->resumeCallable = null;
             }
         } catch (RuntimeException $e) {
-            if (strpos($e->getMessage(), "not master") !== false) {
-                $resumable = true;
+            if ($this->isResumableError($e)) {
+                $this->resume();
             }
-            if ($e->getCode() === self::CURSOR_NOT_FOUND) {
-                $resumable = true;
-            }
-            if ($e instanceof ConnectionTimeoutException) {
-                $resumable = true;
-            }
-        }
-        if ($resumable) {
-            $this->resume();
         }
     }
 
@@ -201,6 +190,30 @@ class ChangeStream implements Iterator
         return $resumeToken;
     }
 
+    /**
+     * Determines if an exception is a resumable error.
+     *
+     * @see https://github.com/mongodb/specifications/blob/master/source/change-streams/change-streams.rst#resumable-error
+     * @param RuntimeException $exception
+     * @return boolean
+     */
+    private function isResumableError(RuntimeException $exception)
+    {
+        if ($exception instanceof ConnectionException) {
+            return true;
+        }
+
+        if ( ! $exception instanceof ServerException) {
+            return false;
+        }
+
+        if (in_array($exception->getCode(), [self::$errorCodeCappedPositionLost, self::$errorCodeCursorKilled, self::$errorCodeInterrupted])) {
+            return false;
+        }
+
+        return true;
+    }
+
     /**
      * Creates a new changeStream after a resumable server error.
      *