Method `textDocument/formatting` returning `AttributeError: 'NoneType' object has no attribute 'get_document'`

[ElliotRoe]

Summary

We are attempting to use the codemirror-languageserver npm package as a client for a remote instance of the python-lsp-server. For the most part, we have been successful and the plugin seamlessly supports autocompletions, linting and syntax checking. Our progress can be found in the demo-project folder of our testing repo.

However, we are struggling to get a simple formatting request to successfully return on a button press. Since the codemirror package has no functionality supporting this, we are just directly sending a formatting request via a websocket following the Microsoft LSP standards. Unfortunately, we're getting a AttributeError: 'NoneType' object has no attribute 'get_document' in response. We are getting the same response for the textDocument/rangeFormatting method as well. Any help would be greatly appreciated, and I'll keep this issue updated as I continue to investigate too. Really, I'm just trying to determine if this is a bug or we are incorrectly using the API. Thanks so much!

Investigation (so far)

• The full error message log looks very similar to AttributeError: 'NoneType' object has no attribute 'get_document' in Kate text editor #545, but downgrading the python-lsp-server to 1.10 did not resolve the issue.
• The error is also very similar to AttributeError: 'NoneType' object has no attribute 'put_document'. #368, but no solution is offered there
• We tried defining workspace folders in the init configuration with no luck
• Looking at the pylsp/python_lsp.py file containing the lines of code causing the error, it seems like the self._match_uri_to_workspace(doc_uri) call is returning a NoneType and then cause the error that is returned. This is confusing me for a couple of reasoning
  • Looking at the full error log, the docUri parameter is defined
  • We've successfully used this document as the target of other LSP methods via the codemirror plugin such as textDocument/didChange (see log below), so I'm unsure why the formatting methods specifically are failing
• I spun up a dev instance of the python-lsp-server to see if custom logging would help shed light on the issue.
  • Logging self.workspaces at the end of m_initialize gives 2024-06-04 12:41:11,980 EDT - DEBUG - pylsp.python_lsp - Workspaces: {'file:///home/': <pylsp.workspace.Workspace object at 0x7fc4801644f0>} meaning the workspace is seemingly correctly defined on initialization
  • However, logging self.workspaces after a m_text_document__formatting call gives 2024-06-04 12:47:47,012 EDT - INFO - pylsp.python_lsp - workspaces {} meaning that either there are two instances of PythonLSPServer or somehow the workspaces attribute is getting overridden
  • I'm very confused, I feel like I have to be missing something obvious here

Relevant Code Snippets

Below are the relevant code snippets and error messages

Initial Config via Codemirror Language Server Client

const ls = languageServer({
      serverUri,
      rootUri: "file:///home/",
      documentUri: "file:///home/index.py",
      languageId: "python",
      workspaceFolders: [
        {
          uri: "file:///home/",
          name: "root",
        },
      ],
    });

    const startState = EditorState.create({
      doc: "# Write your Python code here",
      extensions: [
        basicSetup,
        ls,
        python(),
        lintGutter(),
        indentationMarkers(),
      ],
    });

JSON Request

const formatRequest = {
      jsonrpc: "2.0",
      id: 1,
      method: "textDocument/formatting",
      params: {
        textDocument: {
          uri: "file:///home/index.py",
        },
        options: {
          tabSize: 4,
          insertSpaces: true,
        },
      },
    };

    wsRef.current.send(JSON.stringify(formatRequest));

Full Logs of AttributeError: 'NoneType' object has no attribute 'get_document' Error Message

2024-06-04 11:28:07 2024-06-04 15:28:07,896 UTC - DEBUG - pylsp.python_lsp - consuming payload and feeding it to LSP handler
2024-06-04 11:28:07 2024-06-04 15:28:07,898 UTC - DEBUG - pylsp_jsonrpc.endpoint - Handling request from client {'jsonrpc': '2.0', 'id': 1, 'method': 'textDocument/formatting', 'params': {'textDocument': {'uri': 'file:///home/index.py'}, 'options': {'tabSize': 4, 'insertSpaces': True}}}
2024-06-04 11:28:07 2024-06-04 15:28:07,899 UTC - DEBUG - pylsp_jsonrpc.endpoint - Executing async request handler <function PythonLSPServer.format_document.<locals>.<lambda> at 0xffffa2f6ade0>
2024-06-04 11:28:07 2024-06-04 15:28:07,900 UTC - ERROR - pylsp_jsonrpc.endpoint - Failed to handle request 1
2024-06-04 11:28:07 Traceback (most recent call last):
2024-06-04 11:28:07   File "/usr/local/lib/python3.11/site-packages/pylsp_jsonrpc/endpoint.py", line 234, in callback
2024-06-04 11:28:07     result = future.result()
2024-06-04 11:28:07              ^^^^^^^^^^^^^^^
2024-06-04 11:28:07   File "/usr/local/lib/python3.11/concurrent/futures/_base.py", line 449, in result
2024-06-04 11:28:07     return self.__get_result()
2024-06-04 11:28:07            ^^^^^^^^^^^^^^^^^^^
2024-06-04 11:28:07   File "/usr/local/lib/python3.11/concurrent/futures/_base.py", line 401, in __get_result
2024-06-04 11:28:07     raise self._exception
2024-06-04 11:28:07   File "/usr/local/lib/python3.11/concurrent/futures/thread.py", line 58, in run
2024-06-04 11:28:07     result = self.fn(*self.args, **self.kwargs)
2024-06-04 11:28:07              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
2024-06-04 11:28:07   File "/usr/local/lib/python3.11/site-packages/pylsp/python_lsp.py", line 421, in <lambda>
2024-06-04 11:28:07     return lambda: self._hook("pylsp_format_document", doc_uri, options=options)
2024-06-04 11:28:07                    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
2024-06-04 11:28:07   File "/usr/local/lib/python3.11/site-packages/pylsp/python_lsp.py", line 252, in _hook
2024-06-04 11:28:07     doc = workspace.get_document(doc_uri) if doc_uri else None
2024-06-04 11:28:07           ^^^^^^^^^^^^^^^^^^^^^^
2024-06-04 11:28:07 AttributeError: 'NoneType' object has no attribute 'get_document'
2024-06-04 11:28:07 2024-06-04 15:28:07,903 UTC - DEBUG - asyncio - Using selector: EpollSelector
2024-06-04 11:28:07 2024-06-04 15:28:07,903 UTC - DEBUG - websockets.server - > TEXT '{"jsonrpc":"2.0","id":1,"error":{"code":-32602,...^^^^^^^^^^^^^^^\\n"]}}}' [1274 bytes]

Successful textDocument/didChange method log

2024-06-04 11:28:06 2024-06-04 15:28:06,597 UTC - DEBUG - pylsp.python_lsp - consuming payload and feeding it to LSP handler
2024-06-04 11:28:06 2024-06-04 15:28:06,597 UTC - DEBUG - pylsp_jsonrpc.endpoint - Handling notification from client {'jsonrpc': '2.0', 'method': 'textDocument/didChange', 'params': {'textDocument': {'uri': 'file:///home/index.py', 'version': 19}, 'contentChanges': [{'text': '"Please for the love of god format"'}]}}
2024-06-04 11:28:07 2024-06-04 15:28:07,103 UTC - DEBUG - pylsp.config.config -   pylsp_lint [hook]
2024-06-04 11:28:07       config: <pylsp.config.config.Config object at 0xffffaa594110>
2024-06-04 11:28:07       workspace: <pylsp.workspace.Workspace object at 0xffffaa626190>
2024-06-04 11:28:07       document: file:///home/index.py
2024-06-04 11:28:07       is_saved: False
2024-06-04 11:28:07

[ccordoba12]

Hey @ElliotRoe, thanks for reporting. Quick question because I didn't see it mentioned in your message: did you send a didOpen request before sending the formatting one?

If the document was not added to the workspace, that could be the cause of your error.

[ElliotRoe]

Hi @ccordoba12 ! Thanks for your response. Looking through the code, the codemirror language server client plugin does send a textDocument/didOpen request upon codemirror component initialization (see their code here). This was also confirmed via logs as I found a successful didOpen notification and several didChange notifications before the above error's timestamp. I included a sample of both occurring before the error timestamp in the logs below.

Sample Logs

didOpen notification

2024-06-04 11:27:55 2024-06-04 15:27:55,669 UTC - DEBUG - pylsp_jsonrpc.endpoint - Handling notification from client {'jsonrpc': '2.0', 'method': 'textDocument/didOpen', 'params': {'textDocument': {'uri': 'file:///home/index.py', 'languageId': 'python', 'text': '# Write your Python code here', 'version': 0}}}

didChange notification

2024-06-04 11:27:58 2024-06-04 15:27:58,720 UTC - DEBUG - pylsp_jsonrpc.endpoint - Handling notification from client {'jsonrpc': '2.0', 'method': 'textDocument/didChange', 'params': {'textDocument': {'uri': 'file:///home/index.py', 'version': 1}, 'contentChanges': [{'text': '"# Write your Python code here"'}]}}

Full logs here:

py-lsp.log

[ccordoba12]

Sorry, I don't know what happens. It seems either the document is not registered in the workspace or the initial workspace is not registered as expected.