feat: add image support across web and twilio

src/media/server.ts

@@ -0,0 +1,62 @@
+import fs from "node:fs/promises";
+import path from "node:path";
+import express, { type Express } from "express";
+import type { Server } from "http";
+import { danger } from "../globals.js";
+import { defaultRuntime, type RuntimeEnv } from "../runtime.js";
+import { cleanOldMedia, getMediaDir } from "./store.js";
+
+const DEFAULT_TTL_MS = 2 * 60 * 1000;
+
+export function attachMediaRoutes(
+	app: Express,
+	ttlMs = DEFAULT_TTL_MS,
+	runtime: RuntimeEnv = defaultRuntime,
+) {
+	const mediaDir = getMediaDir();
+
+	app.get("/media/:id", async (req, res) => {
+		const id = req.params.id;
+		const file = path.join(mediaDir, id);
+		try {
+			const stat = await fs.stat(file);
+			if (Date.now() - stat.mtimeMs > ttlMs) {
+				await fs.rm(file).catch(() => {});
+				res.status(410).send("expired");
+				return;
+			}
+			res.sendFile(file);
+			// best-effort single-use cleanup after response ends
+			res.on("finish", () => {
+				setTimeout(() => {
+					fs.rm(file).catch(() => {});
+				}, 500);
+			});
+		} catch {
+			res.status(404).send("not found");
+		}
+	});
+
+	// periodic cleanup
+	setInterval(() => {
+		void cleanOldMedia(ttlMs);
+	}, ttlMs).unref();
+
+}
+
+export async function startMediaServer(
+	port: number,
+	ttlMs = DEFAULT_TTL_MS,
+	runtime: RuntimeEnv = defaultRuntime,
+): Promise<Server> {
+	const app = express();
+	attachMediaRoutes(app, ttlMs, runtime);
+	return await new Promise((resolve, reject) => {
+		const server = app.listen(port);
+		server.once("listening", () => resolve(server));
+		server.once("error", (err) => {
+			runtime.error(danger(`Media server failed: ${String(err)}`));
+			reject(err);
+		});
+	});
+}