CDRIVER-3741 CursorNotFound err is resumable

Author: kevinAlbs

src/libmongoc/src/mongoc/mongoc-change-stream.c

@@ -47,6 +47,10 @@ _is_resumable_error (mongoc_change_stream_t *stream, const bson_t *reply)
       return true;
    }
 
+   if (error.code == MONGOC_SERVER_ERR_CURSOR_NOT_FOUND) {
+      return true;
+   }
+
    if (stream->max_wire_version >= WIRE_VERSION_4_4) {
       return mongoc_error_has_label (reply, "ResumableChangeStreamError");
    }

src/libmongoc/src/mongoc/mongoc-error-private.h

@@ -33,6 +33,7 @@ typedef enum {
 typedef enum {
    MONGOC_SERVER_ERR_HOSTUNREACHABLE = 6,
    MONGOC_SERVER_ERR_HOSTNOTFOUND = 7,
+   MONGOC_SERVER_ERR_CURSOR_NOT_FOUND = 43,
    MONGOC_SERVER_ERR_STALESHARDVERSION = 63,
    MONGOC_SERVER_ERR_NETWORKTIMEOUT = 89,
    MONGOC_SERVER_ERR_SHUTDOWNINPROGRESS = 91,

src/libmongoc/tests/json/change_streams/change-streams-resume-whitelist.json

@@ -1648,6 +1648,102 @@
           }
         ]
       }
+    },
+    {
+      "description": "change stream resumes after CursorNotFound",
+      "minServerVersion": "4.2",
+      "failPoint": {
+        "configureFailPoint": "failCommand",
+        "mode": {
+          "times": 1
+        },
+        "data": {
+          "failCommands": [
+            "getMore"
+          ],
+          "errorCode": 43,
+          "closeConnection": false
+        }
+      },
+      "target": "collection",
+      "topology": [
+        "replicaset",
+        "sharded"
+      ],
+      "changeStreamPipeline": [],
+      "changeStreamOptions": {},
+      "operations": [
+        {
+          "database": "change-stream-tests",
+          "collection": "test",
+          "name": "insertOne",
+          "arguments": {
+            "document": {
+              "x": 1
+            }
+          }
+        }
+      ],
+      "expectations": [
+        {
+          "command_started_event": {
+            "command": {
+              "aggregate": "test",
+              "cursor": {},
+              "pipeline": [
+                {
+                  "$changeStream": {}
+                }
+              ]
+            },
+            "command_name": "aggregate",
+            "database_name": "change-stream-tests"
+          }
+        },
+        {
+          "command_started_event": {
+            "command": {
+              "getMore": 42,
+              "collection": "test"
+            },
+            "command_name": "getMore",
+            "database_name": "change-stream-tests"
+          }
+        },
+        {
+          "command_started_event": {
+            "command": {
+              "aggregate": "test",
+              "cursor": {},
+              "pipeline": [
+                {
+                  "$changeStream": {}
+                }
+              ]
+            },
+            "command_name": "aggregate",
+            "database_name": "change-stream-tests"
+          }
+        }
+      ],
+      "result": {
+        "success": [
+          {
+            "_id": "42",
+            "documentKey": "42",
+            "operationType": "insert",
+            "ns": {
+              "db": "change-stream-tests",
+              "coll": "test"
+            },
+            "fullDocument": {
+              "x": {
+                "$numberInt": "1"
+              }
+            }
+          }
+        ]
+      }
     }
   ]
 }