mcpctl/src/mcpd/tests/stdio-mode.test.ts

/**
 * How mcpd opens a STDIO session: attach to PID 1, or exec a new process.
 *
 * Subtle and silent when wrong. With injected secret delivery the credentials
 * exist ONLY in PID 1's environment (a shell sourced /vault/secrets/<name> and
 * exec'd the server), so an `exec` starts a process with empty credentials —
 * the server comes up, answers tools/list, and fails every authenticated call.
 */
import { describe, it, expect } from 'vitest';
import { chooseStdioMode } from '../src/services/mcp-proxy-service.js';

const base = { name: 's', id: 'id1' };

describe('chooseStdioMode', () => {
  it('attaches for an injector server even though it has a packageName', () => {
    // The regression: packageName would otherwise select exec, and exec loses
    // the secrets entirely.
    expect(chooseStdioMode({ ...base, secretDelivery: 'injector', packageName: '@leval/mcp-grafana' }))
      .toEqual({ kind: 'attach' });
  });

  it('attaches for an injector server even though it has an explicit command', () => {
    expect(chooseStdioMode({ ...base, secretDelivery: 'injector', command: ['node', 'x.js'] }))
      .toEqual({ kind: 'attach' });
  });

  it('still execs a package server on the default env delivery', () => {
    const m = chooseStdioMode({ ...base, secretDelivery: 'env', packageName: '@leval/mcp-grafana', runtime: 'node' });
    expect(m.kind).toBe('exec');
  });

  it('still prefers an explicit command over packageName on env delivery', () => {
    expect(chooseStdioMode({ ...base, secretDelivery: 'env', command: ['node', 'x.js'], packageName: 'p' }))
      .toEqual({ kind: 'exec', command: ['node', 'x.js'] });
  });

  it('attaches for an image-entrypoint server, as before', () => {
    expect(chooseStdioMode({ ...base, dockerImage: 'gitea/mcp:latest' })).toEqual({ kind: 'attach' });
  });

  it('rejects a server with no way to start', () => {
    expect(() => chooseStdioMode({ ...base })).toThrow(/packageName, command, or dockerImage/);
  });
});