Problems starting clojure-lsp via emacs about clojure-lsp

[snoe]

If you're downloading the release, try running it from the command line, it should start up and start reading stdin.
Type {}\n\n and you should get something like:

$ .clojure-lsp
{}

Apr 12, 2019 7:07:02 AM org.eclipse.lsp4j.jsonrpc.json.StreamMessageProducer fireError
SEVERE: Missing header Content-Length in input "{}

"
java.lang.IllegalStateException: Missing header Content-Length in input "{}

If that is ok, I log to /tmp/lsp.out, so watch that file and start your editor, let me know if you get errors there.

LSP Clients also generally have a way to trace server interactions.

In lsp-mode, it looks like:

• lsp-trace - If non-nil, keep a trace of all messages to and from the language server, which can be saved to a file with lsp-save-logs. https://github.com/emacs-lsp/lsp-mode#settings

Turn that on and attach both logs if it's not obvious what's going on.

[ProjectFrank]

Oddly, the /tmp/lsp.out file is not created when clojure-lsp is started using the editor. It is, however, created when I start it using the command line.

I can't get lsp-trace to work, but I tried setting lsp-print-io instead (which I think behaves similarly). This is what that log looks like:

Command "clojure-lsp" is present on the path.
Found the following clients for /Users/me/src/scratch/clojure-lsp/src/clojure_lsp/clojure_core.clj: (server-id clojure-lsp, priority 0)
The following clients were selected based on priority: (server-id clojure-lsp, priority 0)
>>> clojure-lsp:77971 status:starting(async)
Content-Length: 3158

{
  "jsonrpc": "2.0",
  "method": "initialize",
  "params": {
    "processId": 77072,
    "rootPath": "/Users/me/src/scratch/clojure-lsp/",
    "rootUri": "file:///Users/me/src/scratch/clojure-lsp/",
    "capabilities": {
      "workspace": {
        "workspaceEdit": {
          "documentChanges": true,
          "resourceOperations": [
            "create",
            "rename",
            "delete"
          ]
        },
        "applyEdit": true,
        "symbol": {
          "symbolKind": {
            "valueSet": [
              1,
              2,
              3,
              4,
              5,
              6,
              7,
              8,
              9,
              10,
              11,
              12,
              13,
              14,
              15,
              16,
              17,
              18,
              19,
              20,
              21,
              22,
              23,
              24,
              25,
              26
            ]
          }
        },
        "executeCommand": {
          "dynamicRegistration": false
        },
        "didChangeWatchedFiles": {
          "dynamicRegistration": true
        },
        "workspaceFolders": true,
        "configuration": true
      },
      "textDocument": {
        "declaration": {
          "linkSupport": true
        },
        "definition": {
          "linkSupport": true
        },
        "implementation": {
          "linkSupport": true
        },
        "typeDefinition": {
          "linkSupport": true
        },
        "synchronization": {
          "willSave": true,
          "didSave": true,
          "willSaveWaitUntil": true
        },
        "documentSymbol": {
          "symbolKind": {
            "valueSet": [
              1,
              2,
              3,
              4,
              5,
              6,
              7,
              8,
              9,
              10,
              11,
              12,
              13,
              14,
              15,
              16,
              17,
              18,
              19,
              20,
              21,
              22,
              23,
              24,
              25,
              26
            ]
          },
          "hierarchicalDocumentSymbolSupport": true
        },
        "formatting": {
          "dynamicRegistration": true
        },
        "codeAction": {
          "dynamicRegistration": true
        },
        "completion": {
          "completionItem": {
            "snippetSupport": true
          }
        },
        "signatureHelp": {
          "signatureInformation": {
            "parameterInformation": {
              "labelOffsetSupport": true
            }
          }
        },
        "documentLink": {
          "dynamicRegistration": true
        },
        "hover": {
          "contentFormat": [
            "plaintext",
            "markdown"
          ]
        },
        "foldingRange": {
          "dynamicRegistration": true,
          "rangeLimit": null,
          "lineFoldingOnly": null
        }
      }
    },
    "initializationOptions": null
  },
  "id": 8
}

Saving the json rpc part in a text file and piping it to clojure-lsp seems to work fine with the following response:

➜  clojure-lsp git:(6562b07) ✗ clojure-lsp < debug-init.txt
Content-Length: 396

{"jsonrpc":"2.0","id":9,"result":{"capabilities":{"textDocumentSync":{"openClose":true,"change":1,"save":{"includeText":true}},"hoverProvider":true,"completionProvider":{"resolveProvider":false,"triggerCharacters":["c"]},"definitionProvider":true,"referencesProvider":true,"codeActionProvider":true,"documentFormattingProvider":true,"documentRangeFormattingProvider":true,"renameProvider":true}}}

So I guess it's exiting for some reason other than the contents of the message 🤷‍♂️

This is the relevant bit in the *Messages* buffer:

lsp--send-no-wait: clojure-lsp<2>: Cannot communicate with the process (exit)
LSP :: clojure-lsp<2> has exited (exited abnormally with code 126)

It's interesting that the clojure-lsp process seems to exit immediately after being started, since the process takes a few seconds to initialize when started from the command line.

[ProjectFrank]

Some googling tells me that exit code 126 could mean I do not have permission to execute. However, I did run chmod 755 on the executable as directed:

clojure-lsp git:(6562b07) ✗ ls -l ~/bin/clojure-lsp
-rwxr-xr-x  1 me  staff  31955598 12 Apr 08:14 /Users/frankwang/bin/clojure-lsp

Edit: It looks like code 126 could also mean that the thing is not executable.

[snoe]

Hrm, I wonder if the binary needs to be run from a shell, could you try launching with

(lsp-stdio-connection '("bash" "-c" "clojure-lsp"))

[ProjectFrank]

That worked! Thank you so much!

[piotr-yuxuan]

@snoe, thanks for you work on this library! clojure-lsp (along with clj-kondo) have finally put Emacs on par and above IntelliJ for 'professional' code editing in my workflow. I'm super delighted about that!

One note though (perhaps for future reference): on my side I have had to use a custom lsp-clojure-server-command to get lsp server be launched properly:

(use-package lsp-mode
  :commands lsp
  :config
  (dolist (m '(clojure-mode
               clojurec-mode
               clojurescript-mode
               clojurex-mode))
    (add-to-list 'lsp-language-id-configuration `(,m . "clojure")))
  :custom
  ((lsp-clojure-server-command '("bash" "-c" "/Users/piotr-yuxuan/bin/clojure-lsp")) ;; <- here
   (lsp-enable-indentation nil))
  :hook
  (clojure-mode . lsp)
  (clojurec-mode . lsp)
  (clojurescript-mode . lsp))

Without that tweak it looks like bash can't find it, even if /Users/piotr-yuxuan/bin is added to bash $PATH in ~/.bashrc:

*lsp-log*

Command "bash -c clojure-lsp" is present on the path.
Found the following clients for /Users/piotr-yuxuan/src/some-file.clj: (server-id clojure-lsp, priority 0)
The following clients were selected based on priority: (server-id clojure-lsp, priority 0)

*clojure-lsp::stderr*

/bin/bash: clojure-lsp: command not found

Process clojure-lsp stderr finished

*Messages*

LSP :: clojure-lsp has exited (exited abnormally with code 127)
Server clojure-lsp:4086 status:starting exited with status exit. Do you want to restart it? (y or n) n