sinelaw/fresh · error

could not open from container

Error message

could not open {} from container: {}

What it means

fetch_and_open_container_file runs a command (e.g. docker/kubectl exec cat) to extract a file from a container; when that command exits with an error, the first line of its stderr is surfaced in this bail. It means the container-side read of the requested path failed.

Solutions

1. Check the full stderr to see whether the file exists in the container (ls the path via exec).
2. Verify the container is running and the exec command/binary name is correct in the URI.
3. Correct the container path in the URI and retry opening the file.

Example fix

// before
let uri = "container://myapp/etc/hosts"; // file missing
// after
// verify first: docker exec myapp cat /etc/hosts
let uri = "container://myapp//etc/hosts"; // corrected absolute path

// verify the file exists in the container first
// docker exec <container> test -f <path> && echo ok

match editor_open_target(uri) { Err(e) if e.to_string().contains("from container") => show_message(format!("container read failed: {e}")), r => r }

When it happens

Trigger: open_lsp_uri_target resolving a container:// URI where the exec command returns non-zero status — file missing in the container, permission denied, container not running, or the exec binary is unavailable.

Common situations: LSP sends a URI for a file inside a container that was restarted or removed; typo'd container path; container image lacks the file; docker exec fails due to stopped container.

Understand the failure class

Background: "failed to read file", EACCES, ENOENT and "could not read <path>" errors: when a program can't read a file from disk — this error's family across 49 libraries.

Related errors

• Cannot open file: remote connection lost
• ${built.error}
• Cannot save: remote connection lost
• Cannot open files from multiple remote hosts. First
• Cannot mix local and remote files. Use either local paths…

AI-assisted analysis of sinelaw/fresh@67894ca546 (2026-09-13). Data as JSON: /api/errors/753124a1eafc8383. Report an issue: GitHub.

Appendix: source

Thrown at crates/fresh-editor/src/app/file_open_orchestrators.rs:765

        let path_arg = container_path.to_string_lossy().into_owned();
        let result = runtime
            .block_on(spawner.spawn("cat".into(), vec![path_arg], None))
            .map_err(|e| {
                anyhow::anyhow!(
                    "could not open {} from container: {}",
                    container_path.display(),
                    e
                )
            })?;

        if result.exit_code != 0 {
            let first_stderr_line = result
                .stderr
                .lines()
                .next()
                .unwrap_or("(no error message)")
                .trim();
            anyhow::bail!(
                "could not open {} from container: {}",
                container_path.display(),
                first_stderr_line
            );
        }

        self.open_container_only_file(container_path, uri, result.stdout.into_bytes())
    }

    /// Build a buffer from already-fetched container content. The
    /// buffer's `file_path` is the in-container path (so further LSP
    /// requests carry the right URI) and the buffer is read-only —
    /// there is no host writeback path for files that exist only
    /// inside the container. LSP stays enabled so a follow-up
    /// goto-def from the fetched buffer works.
    pub(crate) fn open_container_only_file(
        &mut self,
        container_path: std::path::PathBuf,

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