feat: add basic health check endpoint

src/http/healthCheck.ts

@@ -0,0 +1,34 @@
+import { IncomingMessage, ServerResponse } from 'http'
+const BYTES_IN_MB = 1024 * 1024
+
+export const healthCheck = (_: IncomingMessage, res: ServerResponse) => {
+  res.setHeader('Content-Type', 'application/json')
+
+  try {
+    const memUsage = process.memoryUsage()
+
+    const message = {
+      status: 'Healthy',
+      uptimeHours: Number((process.uptime() / (60 * 60)).toFixed(2)),
+      timestampMs: Date.now(),
+      memoryInfo: {
+        rssMB: Number((memUsage.rss / BYTES_IN_MB).toFixed(1)),
+        heapTotalMB: Number((memUsage.heapTotal / BYTES_IN_MB).toFixed(1)),
+        heapUsedMB: Number((memUsage.heapUsed / BYTES_IN_MB).toFixed(1)),
+        externalMB: Number((memUsage.external / BYTES_IN_MB).toFixed(1))
+      }
+    }
+
+    res.end(JSON.stringify(message))
+  } catch {
+    if (!res.finished) {
+      res.statusCode = 500
+
+      res.end(
+        JSON.stringify({
+          message: 'Unhealthy'
+        })
+      )
+    }
+  }
+}

src/http/index.ts

@@ -1,2 +1,3 @@
 export * from './replay'
 export * from './replaynormalized'
+export * from './healthCheck'

src/tardismachine.ts

@@ -2,7 +2,7 @@ import findMyWay from 'find-my-way'
 import http from 'http'
 import { clearCache, init } from 'tardis-dev'
 import { App, DISABLED, TemplatedApp, WebSocket } from 'uWebSockets.js'
-import { replayHttp, replayNormalizedHttp } from './http'
+import { replayHttp, replayNormalizedHttp, healthCheck } from './http'
 import { replayNormalizedWS, replayWS, streamNormalizedWS } from './ws'
 
 const pkg = require('../package.json')
@@ -29,6 +29,7 @@ export class TardisMachine {
 
     router.on('GET', '/replay', replayHttp)
     router.on('GET', '/replay-normalized', replayNormalizedHttp)
+    router.on('GET', '/health-check', healthCheck)
 
     const wsRoutes = {
       '/ws-replay': replayWS,