make kestrel a tak server, so that it can send and receive pois as cots data

server/utils/shutdown.js

@@ -0,0 +1,68 @@
+/**
+ * Graceful shutdown handler - registers cleanup functions and handles shutdown signals.
+ */
+
+import { SHUTDOWN_TIMEOUT_MS } from './constants.js'
+
+const cleanupFunctions = []
+let isShuttingDown = false
+
+export function clearCleanup() {
+  cleanupFunctions.length = 0
+  isShuttingDown = false
+}
+
+export function registerCleanup(fn) {
+  if (typeof fn !== 'function') throw new TypeError('Cleanup function must be a function')
+  cleanupFunctions.push(fn)
+}
+
+async function executeCleanup() {
+  if (isShuttingDown) return
+  isShuttingDown = true
+  for (let i = cleanupFunctions.length - 1; i >= 0; i--) {
+    try {
+      await cleanupFunctions[i]()
+    }
+    catch (error) {
+      console.error(`[shutdown] Cleanup function ${i} failed:`, error?.message || String(error))
+    }
+  }
+}
+
+export async function graceful(error) {
+  if (error) {
+    console.error('[shutdown] Shutting down due to error:', error?.message || String(error))
+    if (error.stack) console.error('[shutdown] Stack trace:', error.stack)
+  }
+  else {
+    console.log('[shutdown] Initiating graceful shutdown')
+  }
+  const timeout = setTimeout(() => {
+    console.error('[shutdown] Shutdown timeout exceeded, forcing exit')
+    process.exit(1)
+  }, SHUTDOWN_TIMEOUT_MS)
+  try {
+    await executeCleanup()
+    clearTimeout(timeout)
+    console.log('[shutdown] Cleanup complete')
+    process.exit(error ? 1 : 0)
+  }
+  catch (err) {
+    clearTimeout(timeout)
+    console.error('[shutdown] Error during cleanup:', err?.message || String(err))
+    process.exit(1)
+  }
+}
+
+export function initShutdownHandlers() {
+  for (const signal of ['SIGTERM', 'SIGINT']) {
+    process.on(signal, () => {
+      console.log(`[shutdown] Received ${signal}`)
+      graceful().catch((err) => {
+        console.error('[shutdown] Error in graceful shutdown:', err)
+        process.exit(1)
+      })
+    })
+  }
+}