nvim-dap-go remote debug with dlv --headless using launch.json (not working out of the box)

[ppenguin]

I was recently having trouble with a remote debug session. The process:

1. start debugee from the cli with dlv --listen=127.0.0.1:2345 --headless --api-version=2 exec myprog --- [lots of prog arguments]
2. :DapLoadLaunchJSON
3. \dc (which is :DapContinue) => correctly shows a list with debug options including from launch.json
4. Select entry containing the following setup:

   {
     "name": "Attach to remote delve",
     "type": "go",
     "request": "attach",
     "mode": "remote",
     "port": 2345,
     "host": "127.0.0.1",
     "showLog": true,
     "trace": "log",
     "logOutput": "rpc"
   },
   

5. Get error "debugger not found"

If however before step (3) I do:

:lua require("dap").adapters.go = { type = "server", host = "127.0.0.1", port = 2345 }

it works.
Obviously I expect that dap-go sets up the adapter according to the selected launch.json entry.
How to achieve this?

[horriblename]

"type" should probably be the name of the adapter and not the language itself

DAP config is split into dap.adapters.* and dap.configurations.*. adapters are configs of the debugger program, and configurations bind a filetype to adapters.

I'm not really sure what the adapter name is (it's set by dap-go plugin) but you can find them in require('dap').adapters

[ppenguin]

Thanks, sorry for being a bit slow, but in this case adapters.go is the same as the language name? So it might well be the (correct) one from launch.json? But still the adapter config as I understand is set to type = server by my manual action that makes things work, which would be ok for a remote dlv --headless session, but for other cases not, which means one couldn't set it statically anyway.

I guess what I'm getting at is that apparently the action of choosing a config from the launch.json must in this case affect both the debugger and the adapter config, which seems to be not working correctly? And this action must be performed by the dap plugin, so the logical place to look then should be the nvim-dap config, but where/how?

[horriblename]

I just checked, the adapter definition from dap-go is this:

{
  executable = {
    args = { "dap", "-l", "127.0.0.1:${port}" },
    command = "/nix/store/dmdz96wkxav8x5jayr6hbcxfm043wk07-delve-1.23.0/bin/dlv",
    detached = true
  },
  options = {
    initialize_timeout_sec = 20
  },
  port = "${port}",
  type = "server"
}

This kinda rules out the possibility of type = server being sufficient to solve the issue. My knowledge of DAP stuff ends here though, and I can't help you further. Maybe nvim-dap and dap-go folks can help answer this better

[horriblename]

according to dap-go docs

this should work:

    {
      type = "go",
      name = "Attach remote",
      mode = "remote",
      request = "attach",
    }

can you try it? convert to json and put it in launch.json

[ppenguin]

Thanks a lot for your conscientious reply. I'm pretty much AFK for a few days but I'll try asap and get back... Cheers

[ppenguin]

this should work:

    {
      type = "go",
      name = "Attach remote",
      mode = "remote",
      request = "attach",
    }

can you try it? convert to json and put it in launch.json

That's essentially what I had in my OP (ignoring some explicit default values); I tried it again with this in launch.json but it's the same result.