config.ts

mcp-server/src/lib/config.ts

1. import { ConfigError } from "./errors.js";
3. /**
4. * Runtime-agnostic configuration.
5. *
6. * This module reads no globals (no `process.env`). Config is derived from an
7. * injected source so the same core runs under Node (stdio dev) and under the
8. * Cloudflare Workers isolate runtime, where env arrives as a binding on the
9. * fetch handler and `process` does not exist.
10. */
11. export interface PlinthConfig {
12. /** Single dispatch endpoint. Methods are selected via the `method` param. */
13. readonly baseUrl: string;
14. /** Static API key with global read scope. Undefined when none is configured. */
15. readonly apiKey: string | undefined;
16. /**
17. * Master safety switch, true only when PLINTH_ALLOW_LIVE_REQUESTS is "true".
18. * While false, plinthRequest() refuses to run, because the API has no
19. * sandbox: every call reads production data.
20. */
21. readonly allowLiveRequests: boolean;
22. }
24. /**
25. * The subset of environment variables this server reads. Both Node's
26. * `process.env` and a Cloudflare Workers `env` binding are structurally
27. * assignable to this shape.
28. */
29. export interface PlinthEnvVars {
30. PLINTH_API_BASE_URL?: string;
31. PLINTH_API_KEY?: string;
32. PLINTH_ALLOW_LIVE_REQUESTS?: string;
33. }
35. const DEFAULT_BASE_URL = "https://orders.meridiandisplay.example/api/v2/dispatch";
37. /** Build config from an injected env source (process.env, Workers env, a test double). */
38. export function configFromEnv(source: PlinthEnvVars): PlinthConfig {
39. return {
40. baseUrl: source.PLINTH_API_BASE_URL?.trim() || DEFAULT_BASE_URL,
41. apiKey: source.PLINTH_API_KEY?.trim() || undefined,
42. allowLiveRequests: source.PLINTH_ALLOW_LIVE_REQUESTS === "true",
43. };
44. }
46. /**
47. * Assert the config is safe to make a live call with. Called by plinthRequest()
48. * before any network access.
49. */
50. export function assertLiveRequestsAllowed(cfg: PlinthConfig): void {
51. if (!cfg.allowLiveRequests) {
52. throw new ConfigError(
53. "Live requests are disabled. This server is PRODUCTION-only (no sandbox); " +
54. "set PLINTH_ALLOW_LIVE_REQUESTS=true once you have intentionally wired the handlers.",
55. );
56. }
57. if (!cfg.apiKey) {
58. throw new ConfigError("PLINTH_API_KEY is not set.");
59. }
60. }