Malformed bytecode query produces result without requestId

[Daniel C. Weber]

I recently accidentally submitted a malformed bytecode query to Neptune which apparently made it freeze. It didn't really freeze however, it was just that the error response couldn't be mapped to the request because it did not contain the request id of the corresponding request. I was able to reproduce this on the latest Gremlin Server.

The request:

{
  "requestId": "9991b7c5-67f6-4812-9e47-79b54fd0a57c",
  "op": "bytecode",
  "processor": "traversal",
  "args": {
    "gremlin": {
      "@type": "g:Bytecode",
      "@value": {
        "step": [
          ["V"],
          [
            "has",
            "property",
            {
              "@type": "g:P",
              "@value": {
                "predicate":"lt",
                "value": {
                  "@type": "g:List",
                  "@value": [
                    {
                      "@type": "g:Int32",
                      "@value": 1
                    },
                    {
                      "@type": "g:Int32",
                      "@value": 2
                    }
                  ]
                }
              }
            }
          ]
        ]
      }
    },
    "aliases": {
      "g": "g"
    }
  }
}

Note that the P.lt(..) operator is given a list with two entries, which is invalid.

The response:

{
  "requestId": null,
  "status": {
    "message": "Invalid OpProcessor requested [null]",
    "code": 499,
    "attributes": {
      "@type": "g:Map",
      "@value": []
    }
  },
  "result": {
    "data":null,
    "meta": {
      "@type": "g:Map",
      "@value": []
    }
  }
}

The response suggests that the whole request could not be parsed properly (hence maybe the missing request id), but it's really just the query that's malformed, so I guess the request Id should be present.

Happy to help further if needed

Regards

Daniel

[Ken Hu]

Thanks for reporting this. Just curious, which GLV were you using when you found this issue (this probably affects all of them though since the requestId mapping exists in all of them)?

[Daniel C. Weber]

My own (github.com/Gremlinq/ExRam.Gremlinq) which does the websocket-submit/receive loop by itself but still relies on Gremlin.NET for GraphSon-request-serialization.