Method collectMetadata

agent/agent.go:529–576

(ctx context.Context, md codersdk.WorkspaceAgentMetadataDescription, now time.Time)

}

func (a *agent) collectMetadata(ctx context.Context, md codersdk.WorkspaceAgentMetadataDescription, now time.Time) *codersdk.WorkspaceAgentMetadataResult {
	var out bytes.Buffer
	result := &codersdk.WorkspaceAgentMetadataResult{
		// CollectedAt is set here for testing purposes and overrode by
		// coderd to the time of server receipt to solve clock skew.
		//
		// In the future, the server may accept the timestamp from the agent
		// if it can guarantee the clocks are synchronized.
		CollectedAt: now,
	}
	cmdPty, err := a.sshServer.CreateCommand(ctx, md.Script, nil, nil)
	if err != nil {
		result.Error = fmt.Sprintf("create cmd: %+v", err)
		return result
	}
	cmd := cmdPty.AsExec()

	cmd.Stdout = &out
	cmd.Stderr = &out
	cmd.Stdin = io.LimitReader(nil, 0)

	// We split up Start and Wait instead of calling Run so that we can return a more precise error.
	err = cmd.Start()
	if err != nil {
		result.Error = fmt.Sprintf("start cmd: %+v", err)
		return result
	}

	// This error isn't mutually exclusive with useful output.
	err = cmd.Wait()
	const bufLimit = 10 << 10
	if out.Len() > bufLimit {
		err = errors.Join(
			err,
			xerrors.Errorf("output truncated from %v to %v bytes", out.Len(), bufLimit),
		)
		out.Truncate(bufLimit)
	}

	// Important: if the command times out, we may see a misleading error like
	// "exit status 1", so it's important to include the context error.
	err = errors.Join(err, ctx.Err())
	if err != nil {
		result.Error = fmt.Sprintf("run cmd: %+v", err)
	}
	result.Value = out.String()
	return result
}

type metadataResultAndKey struct {
	result *codersdk.WorkspaceAgentMetadataResult