Elixir expert-lsp does not work in remote development

[oddnugget]

Summary

The new elixir language server expert fails to provide completions, hover documentation and jump to definition when used in remote development environments.

Description

The lsp seems to start correctly. Looking at the log-file that expert creates in your-project/.expert/expert.log shows that it is responding to various events emitted by the editor.

[debug] handled notification client -> server workspace/didChangeConfiguration in 7ms
13:45:55.312 [info] ################### opened file:///<REDACTED>/file.ex
13:45:55.312 [debug] handled notification client -> server textDocument/didOpen in 9ms
13:45:55.315 [debug] handled notification client -> server initialized in 13ms

However, no lsp information is displayed in zed itself. Hover does not work, go to definition does not work, nor any other lsp feature. They do still emit events to expert, but the responses seem to not be handled by zed.

Tested with both the automatic installation from zed-extensions/elixir and downloading the nightly binary as specified in the expert-lsp README .

// .config/zed/settings.json (on the remote machine)
{
    "lsp": {
        "expert": {
            "binary": {
                "path": "/home/<REDACTED>/.local/bin/expert_linux_amd64"
            }
        }
    }
}

Another thing to note, is that when restarting the language server (or servers) via zed, it sometimes creates multiple entries of expert. None of the logs there match the logs that expert itself creates in .expert/expert.log

The logfiles accessible through dev: open language server logs are either empty or full of {:erpc, :noconnection} messages.

* (ErlangError) Erlang error: {:erpc, :noconnection}
    (kernel 10.2.7.1) erpc.erl:1376: :erpc.call/5
    (xp_expert 0.1.0-57abaff) lib/expert/state.ex:171: XPExpert.State.apply/2
    (xp_expert 0.1.0-57abaff) lib/expert.ex:200: XPExpert.apply_to_state/2
    (xp_expert 0.1.0-57abaff) lib/expert.ex:139: XPExpert.handle_notification/2
    (xp_gen_lsp 0.11.0) lib/gen_lsp.ex:528: anonymous fn/2 in XPGenLSP.loop/3
    (xp_telemetry 1.3.0) /home/runner/work/expert/expert/apps/expert/deps/telemetry/src/telemetry.erl:324: :xp_telemetry.span/3
    (xp_gen_lsp 0.11.0) lib/gen_lsp.ex:524: anonymous fn/4 in XPGenLSP.loop/3
    (xp_gen_lsp 0.11.0) lib/gen_lsp.ex:601: anonymous fn/4 in XPGenLSP.attempt/4
Received request textDocument/references before engine was initialized. Ignoring.
Received request textDocument/codeAction before engine was initialized. Ignoring.
Received request textDocument/codeAction before engine was initialized. Ignoring.
Received request textDocument/hover before engine was initialized. Ignoring.
Received request textDocument/codeAction before engine was initialized. Ignoring.
Received request textDocument/codeAction before engine was initialized. Ignoring.
Received request textDocument/definition before engine was initialized. Ignoring.

Steps to reproduce:

1. Update zed, update elixir extension
2. Open remote directory
3. Wait for expert to download
4. Try go to definition or hover

Expected Behavior:
It should work
Actual Behavior:
It does not work

Zed Version and System Specs

Zed: v0.201.6 (Zed)
OS: macOS 15.5.0
Memory: 16 GiB
Architecture: aarch64

Remote machine uname -a

Linux devbox 5.15.0-136-generic #147-Ubuntu SMP Sat Mar 15 15:53:30 UTC 2025 x86_64 x86_64 x86_64 GNU/Linux

[oddnugget]

related: zed-industries/zed#37162

[ferrao]

@oddnugget I do not get it to work on local development either... All the responses that I see on the log are:

// Receive:
{"jsonrpc":"2.0","method":"window/logMessage","params":{"message":"Received request textDocument/codeAction before engine was initialized. Ignoring.","type":2}}

[oddnugget]

@ferrao For me it works locally with default settings, but still has issues in remote even after zed-extensions/elixir@0.2.1

[dlebrun]

Same problem as @ferrao. It does not work locally. All I see in the LSP logs is the same "Received request textDocument/codeAction before engine was initialized. Ignoring." message.

The only file I see in [PROJECT_DIR]/.expert is expert.log. Shouldn't there be build files as well?

[ferrao]

Same problem as @ferrao. It does not work locally. All I see in the LSP logs is the same "Received request textDocument/codeAction before engine was initialized. Ignoring." message.

Have you checked v0.2.1 as per #27 @dlebrun ? That fixed it for me, although I got back to elixir-ls, as expert gave me other issues, it probably needs some time to iron everything out.