node: implement live & ready check helpers

node-health/src/liveness.ts

@@ -0,0 +1,31 @@
+/**
+ * Type representing the result of a liveness check.
+ */
+export type LivenessResult = {
+	/** Status of the service (always 'ok'). */
+	status: 'ok';
+	/** Timestamp of the liveness check in milliseconds since the Unix epoch. */
+	timestamp: number;
+};
+
+/**
+ * Liveness check - indicates if the service is running.
+ * @returns A LivenessResult object.
+ */
+export function liveness() {
+	return {
+		status: 'ok',
+		timestamp: Date.now(),
+	} as LivenessResult;
+}
+
+/**
+ * Handler for liveness HTTP requests.
+ * @returns A Response object with LivenessResult in JSON format and status 200.
+ */
+export const handleLiveness = (): Response => {
+	return new Response(JSON.stringify(liveness()), {
+		status: 200,
+		headers: { 'Content-Type': 'application/json' },
+	});
+};