Wrong implementation of GraphQL over WebSocket Error message

[enisdenjo]

Version Information

Server Version: Hasura Cloud

Environment

Cloud

Keywords

graphql-ws,messages,error,websocket

What is the current behaviour?

The error message provides an object with the errors field set to an array of GraphQLErrors.

{
  "type": "error",
  "id": "1",
  "payload": {
    "errors": [
      {
        "extensions": {
          "path": "$.selectionSet.somefield",
          "code": "validation-failed"
        },
        "message": "field \"somefield\" not found in type: 'query_root'"
      }
    ]
  }
}

What is the expected behaviour?

The error message implements the GraphQL over WebSocket Error message.

{
  "type": "error",
  "id": "1",
- "payload": {
-   "errors": [
-     {
-       "extensions": {
-         "path": "$.selectionSet.somefield",
-         "code": "validation-failed"
-       },
-       "message": "field \"somefield\" not found in type: 'query_root'"
-     }
-   ]
- }
+ "payload": [
+   {
+     "extensions": {
+       "path": "$.selectionSet.somefield",
+       "code": "validation-failed"
+     },
+     "message": "field \"somefield\" not found in type: 'query_root'"
+   }
+ ]
}

How to reproduce the issue?

1. Create a project on Hasura Cloud or use mine https://engaging-filly-31.hasura.app/v1/graphql
2. Copy GraphQL API URL
3. Connect using graphql-ws without setting the authorization header (you can use the GraphiQL ❤️ graphql-ws gist)
4. Execute a query with invalid/missing fields
5. Connection Closed: 4400 because the Error message is malformed

Screenshots or Screencast

Any possible solutions?

1. (recommended) Implement the GraphQL over WebSocket Error message when sending GraphQLErrors as presented above.
2. Use the Next message to transmit an error as a part of the GraphQL's ExecutionResult like this:

{
- "type": "error",
+ "type": "next",
  "id": "1",
  "payload": {
    "errors": [
      {
        "extensions": {
          "path": "$.selectionSet.somefield",
          "code": "validation-failed"
        },
        "message": "field \"somefield\" not found in type: 'query_root'"
      }
    ]
  }
}

Additional info

This issue is quite critical for clients using graphql-ws because malformed messages result in immediate connection termination, as per the GraphQL over WebSocket Protocol.

Can you identify the location in the source code where the problem exists?

No.

If the bug is confirmed, would you be willing to submit a PR?

No, I am not familiar with Haskell.

[paritosh-08]

Closed via a886da2