add healthcheck

healthcheck.js

@@ -0,0 +1,23 @@
+const http = require("http");
+const config = require("./config");
+
+const options = {
+  host: "localhost",
+  port: config.PORT,
+  timeout: 2000,
+};
+
+const request = http.request(options, (res) => {
+  if (res.statusCode == 200) {
+    process.exit(0);
+  } else {
+    process.exit(1);
+  }
+});
+
+request.on("error", (err) => {
+  console.log("ERROR");
+  process.exit(1);
+});
+
+request.end();