gleam-lang/gleam · critical

hostname

Error message

hostname

What it means

During Hex OAuth device login, `create_oauth_device_authorisation` (compiler-cli/src/hex/auth.rs:105) builds a recognizable client name `"Gleam (<hostname>)"` for the Hex console. It calls `hostname::get().expect("hostname")`, explicitly assuming gethostname can never fail (the comment says so). If the OS cannot return a hostname, the login flow panics before any HTTP request is sent.

Source

Thrown at compiler-cli/src/hex/auth.rs:105

    fn poll_for_oauth_next_step(
        &mut self,
        device_authorisation: &mut hexpm::OAuthDeviceAuthorisation,
    ) -> Result<hexpm::PollStep, Error> {
        let request = device_authorisation.poll_token_request(&self.hex_config);
        let response = self.runtime.block_on(self.http.send(request))?;
        let next = device_authorisation
            .poll_token_response(response)
            .map_err(Error::hex)?;
        Ok(next)
    }

    fn create_oauth_device_authorisation(
        &mut self,
    ) -> Result<hexpm::OAuthDeviceAuthorisation, Error> {
        // Create a recognisable name for the client, so folks can more easily understand which
        // session is which in the Hex console.
        // It is expected that we can always get the hostname.
        let hostname = hostname::get().expect("hostname");
        let client_name = format!("Gleam ({})", hostname.to_string_lossy());

        let request = hexpm::oauth_device_authorisation_request(
            HEX_OAUTH_CLIENT_ID,
            &client_name,
            &self.hex_config,
        );
        let response = self.runtime.block_on(self.http.send(request))?;
        hexpm::oauth_device_authorisation_response(HEX_OAUTH_CLIENT_ID.to_string(), response)
            .map_err(Error::hex)
    }

    fn encrypt_and_store_oauth_refresh_token(&mut self, tokens: &OAuthTokens) -> Result<(), Error> {
        let path = paths::global_hexpm_oauth_credentials_path();
        let local_password = self.get_local_password()?;
        let encrypted_refresh_token =
            encryption::encrypt_with_passphrase(tokens.refresh_token.as_bytes(), &local_password)
                .map_err(|e| Error::FailedToEncryptLocalHexApiKey {

View on GitHub (pinned to 7e623aa83d)

Solutions

1. Set an explicit hostname: `docker run --hostname gleam-ci ...` or `hostnamectl set-hostname build01` / `hostname build01`
2. Ensure /proc is mounted and readable inside the container/chroot
3. Run `gleam hex authenticate` once on a normal machine and copy the stored credentials (the Hex API key under ~/.config/gleam) into the constrained environment
4. If it still panics, report it upstream — the code treats 'hostname always available' as an invariant, so this path is untested

Example fix

# before: panics with 'hostname' in a stripped container
docker run --rm -v $PWD:/app scratch-ci gleam hex authenticate

# after: give the container a hostname (and /proc)
docker run --rm --hostname gleam-ci -v $PWD:/app scratch-ci gleam hex authenticate

# ensure a hostname is resolvable before OAuth login
[ -n "$(hostname 2>/dev/null)" ] && [ -r /proc/sys/kernel/hostname ] \
  && gleam hex authenticate \
  || echo 'no usable hostname - set one (docker --hostname / hostnamectl) first'

When it happens

Trigger: Running `gleam hex authenticate` (or the first-run OAuth login behind `gleam publish`) in an environment where hostname lookup fails: containers without /proc mounted (hostname::get reads /proc/sys/kernel/hostname on Linux), chroot/namespaces with an unusable hostname, or libc-level gethostname(2) failures in restricted sandboxes.

Common situations: Heavily stripped scratch/distroless containers; minimal VMs whose init never sets a hostname; unusual embedded or sandbox runtimes. Normal desktops, standard Docker (always has a hostname), and CI runners do not hit this.

Related errors

• stdin read_line
• Unable to start Tokio async runtime
• Unable to start Tokio async runtime
• `panic` expression evaluated.
• BEAM compiler instance exited: {status}

AI-assisted analysis of gleam-lang/gleam@7e623aa83d (2026-08-17). Data as JSON: /api/errors/880af8ddaffff56b. Report an issue: GitHub.