chore: establish learning module baseline

OpenMAIC/lib/server/render-service.ts

@@ -0,0 +1,60 @@
+/**
+ * Server-side config + helpers for the isolated MP4 render service (issue #866).
+ *
+ * The render service is an opt-in capability: it's only reachable when
+ * `RENDER_SERVICE_URL` is set. When unset, the app degrades to letting the user
+ * download the project ZIP for local CLI rendering, so callers treat "not
+ * configured" as a normal, expected state — not an error.
+ */
+import { proxyFetch } from '@/lib/server/proxy-fetch';
+import { createLogger } from '@/lib/logger';
+
+const log = createLogger('RenderService');
+
+/** The configured base URL of the render service, or null when the capability is off. */
+export function getRenderServiceUrl(): string | null {
+  const raw = process.env.RENDER_SERVICE_URL?.trim();
+  return raw ? raw.replace(/\/+$/, '') : null;
+}
+
+/** Whether the render service is configured (URL present — not a reachability check). */
+export function isRenderServiceConfigured(): boolean {
+  return getRenderServiceUrl() !== null;
+}
+
+/**
+ * Resolve the render service base URL, or `{ error: 'not_configured' }`.
+ *
+ * `RENDER_SERVICE_URL` is operator-supplied deployment config, not user input,
+ * so it is deliberately NOT run through the SSRF guard: the guard exists to stop
+ * user-controlled URLs from reaching internal hosts, whereas this URL is
+ * *meant* to point at an internal service (e.g. `http://render-service:9000`
+ * on the compose network). Running the guard here would reject the intended
+ * deployment unless the operator globally weakened SSRF via
+ * `ALLOW_LOCAL_NETWORKS`, which we do not want to require.
+ */
+export function resolveRenderServiceUrl(): { url: string } | { error: 'not_configured' } {
+  const url = getRenderServiceUrl();
+  return url ? { url } : { error: 'not_configured' };
+}
+
+/**
+ * Whether the configured render service is actually reachable and healthy.
+ * Probes `GET /health` with a short timeout. Returns false (rather than
+ * throwing) when unconfigured or unreachable, so the capability endpoint can
+ * report a truthful enabled/disabled state and the UI degrades cleanly.
+ */
+export async function checkRenderServiceHealth(): Promise<boolean> {
+  const url = getRenderServiceUrl();
+  if (!url) return false;
+  try {
+    const res = await proxyFetch(`${url}/health`, {
+      method: 'GET',
+      signal: AbortSignal.timeout(3000),
+    });
+    return res.ok;
+  } catch (error) {
+    log.info('Render service health check failed:', error instanceof Error ? error.message : error);
+    return false;
+  }
+}