server.test.js

/**
 * Tests for api-proxy server.js
 */

const { deriveCopilotApiTarget } = require('./server');

describe('deriveCopilotApiTarget', () => {
  let originalEnv;

  beforeEach(() => {
    // Save original env vars
    originalEnv = {
      COPILOT_API_TARGET: process.env.COPILOT_API_TARGET,
      GITHUB_SERVER_URL: process.env.GITHUB_SERVER_URL,
    };
    // Clear env vars before each test
    delete process.env.COPILOT_API_TARGET;
    delete process.env.GITHUB_SERVER_URL;
  });

  afterEach(() => {
    // Restore original env vars
    if (originalEnv.COPILOT_API_TARGET !== undefined) {
      process.env.COPILOT_API_TARGET = originalEnv.COPILOT_API_TARGET;
    } else {
      delete process.env.COPILOT_API_TARGET;
    }
    if (originalEnv.GITHUB_SERVER_URL !== undefined) {
      process.env.GITHUB_SERVER_URL = originalEnv.GITHUB_SERVER_URL;
    } else {
      delete process.env.GITHUB_SERVER_URL;
    }
  });

  describe('COPILOT_API_TARGET env var (highest priority)', () => {
    it('should return COPILOT_API_TARGET when explicitly set', () => {
      process.env.COPILOT_API_TARGET = 'custom.api.com';
      expect(deriveCopilotApiTarget()).toBe('custom.api.com');
    });

    it('should prefer COPILOT_API_TARGET over GITHUB_SERVER_URL', () => {
      process.env.COPILOT_API_TARGET = 'custom.api.com';
      process.env.GITHUB_SERVER_URL = 'https://mycompany.ghe.com';
      expect(deriveCopilotApiTarget()).toBe('custom.api.com');
    });
  });

  describe('GitHub Enterprise Cloud (*.ghe.com)', () => {
    it('should derive copilot-api.<subdomain>.ghe.com for GHEC tenants', () => {
      process.env.GITHUB_SERVER_URL = 'https://mycompany.ghe.com';
      expect(deriveCopilotApiTarget()).toBe('copilot-api.mycompany.ghe.com');
    });

    it('should handle GHEC URLs with trailing slash', () => {
      process.env.GITHUB_SERVER_URL = 'https://example.ghe.com/';
      expect(deriveCopilotApiTarget()).toBe('copilot-api.example.ghe.com');
    });

    it('should handle GHEC URLs with path components', () => {
      process.env.GITHUB_SERVER_URL = 'https://acme.ghe.com/some/path';
      expect(deriveCopilotApiTarget()).toBe('copilot-api.acme.ghe.com');
    });

    it('should handle multi-part subdomain for GHEC', () => {
      process.env.GITHUB_SERVER_URL = 'https://dev.mycompany.ghe.com';
      expect(deriveCopilotApiTarget()).toBe('copilot-api.dev.mycompany.ghe.com');
    });
  });

  describe('GitHub Enterprise Server (GHES)', () => {
    it('should return api.enterprise.githubcopilot.com for GHES', () => {
      process.env.GITHUB_SERVER_URL = 'https://github.example.com';
      expect(deriveCopilotApiTarget()).toBe('api.enterprise.githubcopilot.com');
    });

    it('should handle GHES with IP address', () => {
      process.env.GITHUB_SERVER_URL = 'https://192.168.1.100';
      expect(deriveCopilotApiTarget()).toBe('api.enterprise.githubcopilot.com');
    });

    it('should handle GHES with custom port', () => {
      process.env.GITHUB_SERVER_URL = 'https://github.internal:8443';
      expect(deriveCopilotApiTarget()).toBe('api.enterprise.githubcopilot.com');
    });
  });

  describe('GitHub.com (public)', () => {
    it('should return api.githubcopilot.com for github.com', () => {
      process.env.GITHUB_SERVER_URL = 'https://github.com';
      expect(deriveCopilotApiTarget()).toBe('api.githubcopilot.com');
    });

    it('should handle github.com with trailing slash', () => {
      process.env.GITHUB_SERVER_URL = 'https://github.com/';
      expect(deriveCopilotApiTarget()).toBe('api.githubcopilot.com');
    });

    it('should handle github.com with path', () => {
      process.env.GITHUB_SERVER_URL = 'https://github.com/github/hub';
      expect(deriveCopilotApiTarget()).toBe('api.githubcopilot.com');
    });
  });

  describe('Default behavior', () => {
    it('should return api.githubcopilot.com when no env vars are set', () => {
      expect(deriveCopilotApiTarget()).toBe('api.githubcopilot.com');
    });

    it('should return default when GITHUB_SERVER_URL is empty string', () => {
      process.env.GITHUB_SERVER_URL = '';
      expect(deriveCopilotApiTarget()).toBe('api.githubcopilot.com');
    });

    it('should return default when GITHUB_SERVER_URL is invalid', () => {
      process.env.GITHUB_SERVER_URL = 'not-a-valid-url';
      expect(deriveCopilotApiTarget()).toBe('api.githubcopilot.com');
    });

    it('should return default when GITHUB_SERVER_URL is malformed', () => {
      process.env.GITHUB_SERVER_URL = 'ht!tp://bad-url';
      expect(deriveCopilotApiTarget()).toBe('api.githubcopilot.com');
    });
  });
});