Connect to an opencode instance running in a container

[Rom888]

Hi!
I have an opencode instance running in a podman container with
podman run -it ...
and it works fine in the gnome terminal.
How can I connect to it from nvim on the host machine?

':checkhealth opencode' shows this:

• ❌ ERROR opencode executable not found in $PATH.
  • ADVICE:
    • Install opencode and ensure it's in your $PATH.

[NickvanDyke]

Hmm, I think you could:

1. Launch opencode in the container with --port <port>
2. Map that container port to a host port
3. Set vim.g.opencode_opts.port = <port>

Then the plugin will communicate with opencode in the container 😀

[Rom888]

Thanks for the hint, I didn't know about --port option.

Unfortunately, I got the error in nvim when trying to toggle opencode:

E5108: Error executing lua: `provider.toggle` unavailable — run `:checkhealth opencode` for details
stack traceback:
	[C]: in function 'error'
	...endor/start/opencode.nvim/lua/opencode/provider/init.lua:85: in function 'toggle'
	/home/rom/.config/nvim/plugin/opencode.nvim.lua:15: in function </home/rom/.config/nvim/plugin/opencode.nvim.lua:15>

checkhealth opencode:

opencode:                                   require("opencode.health").check()

opencode.nvim ~
- ✅ OK `nvim` version: `0.11.1+ga9a3981669`.
- ✅ OK `opencode.nvim` git commit hash: `8b737e45b8e665a0c1111d615b314951d8168a44`.
- ✅ OK `vim.g.opencode_opts`: {
    port = 61630
  }

opencode.nvim [binaries] ~
- ❌ ERROR `opencode` executable not found in `$PATH`.
  - ADVICE:
    - Install `opencode` and ensure it's in your `$PATH`.
- ✅ OK `curl` available.
- ✅ OK `pgrep` available: it will be used to auto-find `opencode` if `vim.g.opencode_opts.port` is not set.
- ✅ OK `lsof` available: it will be used to auto-find `opencode` if `vim.g.opencode_opts.port` is not set.

opencode.nvim.lua:

vim.g.opencode_opts = {
  -- Your configuration, if any — see `lua/opencode/config.lua`, or "goto definition".
  port = 50000
}

-- Required for `opts.events.reload`.
vim.o.autoread = true

I started opencode using:
opencode acp --port 50000 --print-logs --log-level INFO

this url works in my browser:
http://127.0.0.1:50000

Do you know the way I can test if the ACP server with --port is working right using curl or any other cli tools?

[NickvanDyke]

You can ignore the provider and "missing opencode" errors; they won't make much sense when you're running opencode in a container. Don't use toggle() in this case - just ask() and select(). Those will connect to the already-running opencode in the container 🙂

opencode offers a non-ACP API, which opencode.nvim uses. So maybe try it without acp? opencode --port 50000 --print-logs --log-level INFO

[Rom888]

You are right, it works without acp:
opencode --port 50000

I now have containerized opencode with TUI and restricted network and directories access.
And I can control it from nvim using opencode.nvim

Thank you!

[NickvanDyke]

Yay! Thanks for the interesting question! I'm sure others will find this a helpful reference.

I presume podman has a CLI to start/stop containers? So you could create a custom Provider for opencode.nvim to start/stop it on your behalf for convenience. Just a thought!

[Rom888]

I created a bash script with rootless podman named 'opencode-opencode.nvim' which I can run in a terminal to see opencode TUI.
It looks like this:

#!/bin/bash

appName=opencode
params=(--rm --name "$appName")
params+=(--userns keep-id)

# The most robust solution is to ensure that the container starts an init process that is responsible for handling signals correctly and cleaning up orphaned processes. When a container runs with an init process, signals sent to the container process are properly forwarded to the application inside (e.g., opencode).
params+=(--init)

# other params here to bind directories, restrict network access, support clipboard sharing, set workdir, ...

# publish container port to host port, containerPort:hostPort
publishPort=50000
params+=(--publish "$publishPort:$publishPort")

params+=(-it)
podman run "${params[@]}" "$appName" opencode --port $publishPort

The similar approach finally works with the stdio opencode transport, in this case the bash script is named 'opencode', located in a $PATH dir, and the last lines looks like:

params+=(-i)
podman run "${params[@]}" "$appName" opencode "$@"