From d4713cae012d7d05ed9264d6cbba2c3d1935c7c6 Mon Sep 17 00:00:00 2001
From: Alex Gleason <alex@alexgleason.me>
Date: Thu, 4 Jul 2024 23:53:20 +0100
Subject: [PATCH 1/2] Move errorHandler to a separate file

---
 src/app.ts               |  8 ++------
 src/controllers/error.ts | 11 +++++++++++
 2 files changed, 13 insertions(+), 6 deletions(-)
 create mode 100644 src/controllers/error.ts

diff --git a/src/app.ts b/src/app.ts
index 4c0ffc7e..f7f4f29a 100644
--- a/src/app.ts
+++ b/src/app.ts
@@ -108,6 +108,7 @@ import {
   trendingStatusesController,
   trendingTagsController,
 } from '@/controllers/api/trends.ts';
+import { errorHandler } from '@/controllers/error.ts';
 import { metricsController } from '@/controllers/metrics.ts';
 import { indexController } from '@/controllers/site.ts';
 import { nodeInfoController, nodeInfoSchemaController } from '@/controllers/well-known/nodeinfo.ts';
@@ -340,12 +341,7 @@ app.get('/', frontendController, indexController);
 // Fallback
 app.get('*', publicFiles, staticFiles, frontendController);
 
-app.onError((err, c) => {
-  if (err.message === 'canceling statement due to statement timeout') {
-    return c.json({ error: 'The server was unable to respond in a timely manner' }, 500);
-  }
-  return c.json({ error: 'Something went wrong' }, 500);
-});
+app.onError(errorHandler);
 
 export default app;
 
diff --git a/src/controllers/error.ts b/src/controllers/error.ts
new file mode 100644
index 00000000..fa5e4d32
--- /dev/null
+++ b/src/controllers/error.ts
@@ -0,0 +1,11 @@
+import { ErrorHandler } from '@hono/hono';
+
+export const errorHandler: ErrorHandler = (err, c) => {
+  console.error(err);
+
+  if (err.message === 'canceling statement due to statement timeout') {
+    return c.json({ error: 'The server was unable to respond in a timely manner' }, 500);
+  }
+
+  return c.json({ error: 'Something went wrong' }, 500);
+};

From 96a8ccb2e637ffdf1fec979007377d46d321750f Mon Sep 17 00:00:00 2001
From: Alex Gleason <alex@alexgleason.me>
Date: Fri, 5 Jul 2024 00:00:57 +0100
Subject: [PATCH 2/2] HTTP Response metrics

---
 src/app.ts                          | 15 +++++++--------
 src/metrics.ts                      |  6 ++++++
 src/middleware/metricsMiddleware.ts |  6 +++++-
 3 files changed, 18 insertions(+), 9 deletions(-)

diff --git a/src/app.ts b/src/app.ts
index f7f4f29a..1cb3746b 100644
--- a/src/app.ts
+++ b/src/app.ts
@@ -152,18 +152,17 @@ if (Conf.cronEnabled) {
 
 app.use('*', rateLimitMiddleware(300, Time.minutes(5)));
 
-app.use('/api/*', logger(debug));
-app.use('/.well-known/*', logger(debug));
-app.use('/users/*', logger(debug));
-app.use('/nodeinfo/*', logger(debug));
-app.use('/oauth/*', logger(debug));
+app.use('/api/*', metricsMiddleware, logger(debug));
+app.use('/.well-known/*', metricsMiddleware, logger(debug));
+app.use('/users/*', metricsMiddleware, logger(debug));
+app.use('/nodeinfo/*', metricsMiddleware, logger(debug));
+app.use('/oauth/*', metricsMiddleware, logger(debug));
 
-app.get('/api/v1/streaming', streamingController);
-app.get('/relay', relayController);
+app.get('/api/v1/streaming', metricsMiddleware, streamingController);
+app.get('/relay', metricsMiddleware, relayController);
 
 app.use(
   '*',
-  metricsMiddleware,
   cspMiddleware(),
   cors({ origin: '*', exposeHeaders: ['link'] }),
   signerMiddleware,
diff --git a/src/metrics.ts b/src/metrics.ts
index 96d91599..67da3f49 100644
--- a/src/metrics.ts
+++ b/src/metrics.ts
@@ -6,6 +6,12 @@ export const httpRequestCounter = new Counter({
   labelNames: ['method'],
 });
 
+export const httpResponseCounter = new Counter({
+  name: 'http_responses_total',
+  help: 'Total number of HTTP responses',
+  labelNames: ['status', 'path'],
+});
+
 export const streamingConnectionsGauge = new Gauge({
   name: 'streaming_connections',
   help: 'Number of active connections to the streaming API',
diff --git a/src/middleware/metricsMiddleware.ts b/src/middleware/metricsMiddleware.ts
index 1a491186..d7ac43d5 100644
--- a/src/middleware/metricsMiddleware.ts
+++ b/src/middleware/metricsMiddleware.ts
@@ -1,10 +1,14 @@
 import { MiddlewareHandler } from '@hono/hono';
 
-import { httpRequestCounter } from '@/metrics.ts';
+import { httpRequestCounter, httpResponseCounter } from '@/metrics.ts';
 
 export const metricsMiddleware: MiddlewareHandler = async (c, next) => {
   const { method } = c.req;
   httpRequestCounter.inc({ method });
 
   await next();
+
+  const { status } = c.res;
+  const path = c.req.matchedRoutes.find((r) => r.method !== 'ALL')?.path ?? c.req.routePath;
+  httpResponseCounter.inc({ status, path });
 };