Checkpoint: v4.0 media service, compose deploy, and verified docs

server/_core/mediaProxy.ts

@@ -0,0 +1,56 @@
+import type { Express, RequestHandler } from "express";
+import http from "node:http";
+import https from "node:https";
+
+function createMediaProxy(targetUrl: string): RequestHandler {
+  const target = new URL(targetUrl);
+  const transport = target.protocol === "https:" ? https : http;
+
+  return (req, res) => {
+    const upstreamUrl = new URL(req.originalUrl, target);
+    const proxyRequest = transport.request(
+      upstreamUrl,
+      {
+        method: req.method,
+        headers: {
+          ...req.headers,
+          host: target.host,
+          connection: "keep-alive",
+        },
+      },
+      (proxyResponse) => {
+        if (proxyResponse.statusCode) {
+          res.status(proxyResponse.statusCode);
+        }
+        Object.entries(proxyResponse.headers).forEach(([key, value]) => {
+          if (value !== undefined) {
+            res.setHeader(key, value);
+          }
+        });
+        proxyResponse.pipe(res);
+      }
+    );
+
+    proxyRequest.on("error", (error) => {
+      if (!res.headersSent) {
+        res.status(502).json({
+          error: "media_service_unavailable",
+          message: error.message,
+        });
+      } else {
+        res.end();
+      }
+    });
+
+    req.pipe(proxyRequest);
+  };
+}
+
+export function registerMediaProxy(app: Express) {
+  const mediaServiceUrl = process.env.MEDIA_SERVICE_URL;
+  if (!mediaServiceUrl) {
+    return;
+  }
+
+  app.use("/media", createMediaProxy(mediaServiceUrl));
+}