Cloudflare Prometheus Exporter

src/worker.tsx

@@ -0,0 +1,128 @@
+import { env } from "cloudflare:workers";
+import { Hono } from "hono";
+import { LandingPage } from "./components/LandingPage";
+import { AccountMetricCoordinator } from "./durable-objects/AccountMetricCoordinator";
+import { MetricCoordinator } from "./durable-objects/MetricCoordinator";
+import { MetricExporter } from "./durable-objects/MetricExporter";
+import { type AppConfig, parseConfig } from "./lib/config";
+import { checkHealth, healthResponse } from "./lib/health";
+import { configFromEnv, createLogger } from "./lib/logger";
+import {
+	ConfigKeySchema,
+	getConfig,
+	getConfigKey,
+	getEnvDefaults,
+	resetAllConfig,
+	resetConfigKey,
+	setConfigKey,
+} from "./lib/runtime-config";
+
+export { MetricCoordinator, AccountMetricCoordinator, MetricExporter };
+
+type Variables = { config: AppConfig };
+
+const app = new Hono<{ Bindings: Env; Variables: Variables }>();
+
+// Parse config middleware
+app.use("*", async (c, next) => {
+	c.set("config", parseConfig(c.env));
+	await next();
+});
+
+// Disable guards
+app.use("*", async (c, next) => {
+	const path = c.req.path;
+	if (c.var.config.disableUi && path === "/") {
+		return c.text("Not Found", 404);
+	}
+	if (c.var.config.disableConfigApi && path.startsWith("/config")) {
+		return c.text("Not Found", 404);
+	}
+	await next();
+});
+
+// Dynamic metrics path middleware (runs before routing)
+app.get(env.METRICS_PATH, async (c) => {
+	const logger = createLogger("worker", configFromEnv(c.env)).withContext({
+		request_id: crypto.randomUUID(),
+	});
+	logger.info("Metrics request received");
+
+	try {
+		const coordinator = await MetricCoordinator.get(c.env);
+		const output = await coordinator.export();
+		logger.info("Metrics exported successfully");
+		return c.text(output, 200, {
+			"Content-Type": "text/plain; charset=utf-8",
+		});
+	} catch (error) {
+		const message = error instanceof Error ? error.message : String(error);
+		logger.error("Failed to collect metrics", { error: message });
+		return c.text(`Error collecting metrics: ${message}`, 500);
+	}
+});
+
+// Routes
+app.get("/", (c) => c.html(<LandingPage config={c.var.config} />));
+
+app.get("/health", async (c) => {
+	const health = await checkHealth(c.env);
+	return healthResponse(health);
+});
+
+// Config API routes
+app.get("/config", async (c) => {
+	const config = await getConfig(c.env);
+	return c.json(config);
+});
+
+app.get("/config/defaults", (c) => {
+	const defaults = getEnvDefaults(c.env);
+	return c.json(defaults);
+});
+
+app.get("/config/:key", async (c) => {
+	const keyResult = ConfigKeySchema.safeParse(c.req.param("key"));
+	if (!keyResult.success) {
+		return c.json({ error: "Invalid config key" }, 400);
+	}
+	const value = await getConfigKey(c.env, keyResult.data);
+	return c.json({ key: keyResult.data, value });
+});
+
+app.put("/config/:key", async (c) => {
+	const keyResult = ConfigKeySchema.safeParse(c.req.param("key"));
+	if (!keyResult.success) {
+		return c.json({ error: "Invalid config key" }, 400);
+	}
+	const body = await c.req.json<{ value: unknown }>().catch(() => null);
+	if (!body || !("value" in body)) {
+		return c.json({ error: "Request body must contain 'value'" }, 400);
+	}
+	const result = await setConfigKey(c.env, keyResult.data, body.value);
+	if (!result.success) {
+		return c.json(
+			{ error: "Invalid value", details: result.error.issues },
+			400,
+		);
+	}
+	return c.json(result.config);
+});
+
+app.delete("/config/:key", async (c) => {
+	const keyResult = ConfigKeySchema.safeParse(c.req.param("key"));
+	if (!keyResult.success) {
+		return c.json({ error: "Invalid config key" }, 400);
+	}
+	const config = await resetConfigKey(c.env, keyResult.data);
+	return c.json(config);
+});
+
+app.delete("/config", async (c) => {
+	const config = await resetAllConfig(c.env);
+	return c.json(config);
+});
+
+app.notFound((c) => c.text("Not Found", 404));
+
+export default app;