WC-2695 Add better visibility for router-worker

.changeset/poor-shoes-tickle.md

@@ -0,0 +1,5 @@
+---
+"@cloudflare/workers-shared": minor
+---
+
+feat: Add observability to router-worker

packages/workers-shared/router-worker/src/analytics.ts

@@ -0,0 +1,71 @@
+import type { Environment, ReadyAnalytics } from "./types";
+
+// This will allow us to make breaking changes to the analytic schema
+const VERSION = 1;
+
+export enum DISPATCH_TYPE {
+	ASSETS = "asset",
+	WORKER = "worker",
+}
+
+// When adding new columns please update the schema
+type Data = {
+	// -- Doubles --
+	// double1 - The time it takes for the whole request to complete in milliseconds
+	requestTime?: number;
+	// double2 - Colo ID
+	coloId?: number;
+	// double3 - Metal ID
+	metalId?: number;
+	// double4 - Colo tier (e.g. tier 1, tier 2, tier 3)
+	coloTier?: number;
+
+	// -- Blobs --
+	// blob1 - Hostname of the request
+	hostname?: string;
+	// blob2 - Dispatch type - what kind of thing did we dispatch
+	dispatchtype?: DISPATCH_TYPE;
+	// blob3 - Error message
+	error?: string;
+	// blob4 - The current version UUID of router-server
+	version?: string;
+	// blob5 - Region of the colo (e.g. WEUR)
+	coloRegion?: string;
+};
+
+export class Analytics {
+	private data: Data = {};
+
+	setData(newData: Partial<Data>) {
+		this.data = { ...this.data, ...newData };
+	}
+
+	getData(key: keyof Data) {
+		return this.data[key];
+	}
+
+	write(env: Environment, readyAnalytics?: ReadyAnalytics, hostname?: string) {
+		if (!readyAnalytics) {
+			return;
+		}
+
+		readyAnalytics.logEvent({
+			version: VERSION,
+			accountId: 0, // TODO: need to plumb through
+			indexId: hostname,
+			doubles: [
+				this.data.requestTime ?? -1, // double1
+				this.data.coloId ?? -1, // double2
+				this.data.metalId ?? -1, // double3
+				this.data.coloTier ?? -1, // double4
+			],
+			blobs: [
+				this.data.hostname?.substring(0, 256), // blob1 - trim to 256 bytes
+				this.data.dispatchtype, // blob2
+				this.data.error?.substring(0, 256), // blob3 - trim to 256 bytes
+				this.data.version, // blob4
+				this.data.coloRegion, // blob5
+			],
+		});
+	}
+}

packages/workers-shared/router-worker/src/index.ts

@@ -1,13 +1,26 @@
 import { setupSentry } from "../../utils/sentry";
+import { Analytics, DISPATCH_TYPE } from "./analytics";
+import { PerformanceTimer } from "./performance";
 import type AssetWorker from "../../asset-worker/src/index";
 import type { RoutingConfig } from "../../utils/types";
+import type {
+	ColoMetadata,
+	Environment,
+	ReadyAnalytics,
+	UnsafePerformanceTimer,
+} from "./types";
 
 interface Env {
 	ASSET_WORKER: Service<AssetWorker>;
 	USER_WORKER: Fetcher;
 	CONFIG: RoutingConfig;
 
 	SENTRY_DSN: string;
+	ENVIRONMENT: Environment;
+	ANALYTICS: ReadyAnalytics;
+	COLO_METADATA: ColoMetadata;
+	UNSAFE_PERFORMANCE: UnsafePerformanceTimer;
+	VERSION_METADATA: WorkerVersionMetadata;
 
 	SENTRY_ACCESS_CLIENT_ID: string;
 	SENTRY_ACCESS_CLIENT_SECRET: string;
@@ -16,7 +29,9 @@ interface Env {
 export default {
 	async fetch(request: Request, env: Env, ctx: ExecutionContext) {
 		let sentry: ReturnType<typeof setupSentry> | undefined;
-		const maybeSecondRequest = request.clone();
+		const analytics = new Analytics();
+		const performance = new PerformanceTimer(env.UNSAFE_PERFORMANCE);
+		const startTimeMs = performance.now();
 
 		try {
 			sentry = setupSentry(
@@ -27,21 +42,50 @@ export default {
 				env.SENTRY_ACCESS_CLIENT_SECRET
 			);
 
+			const url = new URL(request.url);
+			if (sentry) {
+				sentry.setUser({ username: url.hostname });
+				sentry.setTag("colo", env.COLO_METADATA.coloId);
+				sentry.setTag("metal", env.COLO_METADATA.metalId);
+			}
+
+			if (env.COLO_METADATA && env.VERSION_METADATA) {
+				analytics.setData({
+					coloId: env.COLO_METADATA.coloId,
+					metalId: env.COLO_METADATA.metalId,
+					coloTier: env.COLO_METADATA.coloTier,
+					coloRegion: env.COLO_METADATA.coloRegion,
+					hostname: url.hostname,
+					version: env.VERSION_METADATA.id,
+				});
+			}
+
+			const maybeSecondRequest = request.clone();
 			if (env.CONFIG.has_user_worker) {
 				if (await env.ASSET_WORKER.unstable_canFetch(request)) {
+					analytics.setData({ dispatchtype: DISPATCH_TYPE.ASSETS });
 					return await env.ASSET_WORKER.fetch(maybeSecondRequest);
 				} else {
+					analytics.setData({ dispatchtype: DISPATCH_TYPE.WORKER });
 					return env.USER_WORKER.fetch(maybeSecondRequest);
 				}
 			}
 
+			analytics.setData({ dispatchtype: DISPATCH_TYPE.ASSETS });
 			return await env.ASSET_WORKER.fetch(request);
 		} catch (err) {
+			if (err instanceof Error) {
+				analytics.setData({ error: err.message });
+			}
+
 			// Log to Sentry if we can
 			if (sentry) {
 				sentry.captureException(err);
 			}
 			throw err;
+		} finally {
+			analytics.setData({ requestTime: performance.now() - startTimeMs });
+			analytics.write(env.ENVIRONMENT, env.ANALYTICS);
 		}
 	},
 };

packages/workers-shared/router-worker/src/performance.ts

@@ -0,0 +1,16 @@
+import type { UnsafePerformanceTimer } from "./types";
+
+export class PerformanceTimer {
+	private performanceTimer;
+
+	constructor(performanceTimer?: UnsafePerformanceTimer) {
+		this.performanceTimer = performanceTimer;
+	}
+
+	now() {
+		if (this.performanceTimer) {
+			return this.performanceTimer.timeOrigin + this.performanceTimer.now();
+		}
+		return Date.now();
+	}
+}

packages/workers-shared/router-worker/src/types.ts

@@ -0,0 +1,25 @@
+export type Environment = "production" | "staging";
+
+export interface ReadyAnalytics {
+	logEvent: (e: ReadyAnalyticsEvent) => void;
+}
+
+export interface ColoMetadata {
+	metalId: number;
+	coloId: number;
+	coloRegion: string;
+	coloTier: number;
+}
+
+export interface UnsafePerformanceTimer {
+	readonly timeOrigin: number;
+	now: () => number;
+}
+
+export interface ReadyAnalyticsEvent {
+	accountId?: number;
+	indexId?: string;
+	version?: number;
+	doubles?: (number | undefined)[];
+	blobs?: (string | undefined)[];
+}

packages/workers-shared/router-worker/wrangler.toml

@@ -13,6 +13,9 @@ workers_dev = false
 main = "src/index.ts"
 compatibility_date = "2024-07-31"
 
+[version_metadata]
+binding = "VERSION_METADATA"
+
 [[unsafe.bindings]]
 name = "CONFIG"
 type = "param"
@@ -29,4 +32,8 @@ type = "origin"
 
 [unsafe.metadata.build_options]
 stable_id = "cloudflare/cf_router_worker"
-networks = ["cf","jdc"]
+networks = ["cf","jdc"]
+
+[[unsafe.bindings]]
+name = "workers-router-worker"
+type = "internal_capability_grants"