app.js

var express = require("express");
var app = express();
const PG_CONFIG = {
  user: process.env.DB_USER,
  host: process.env.DB_HOST.match(/(.*):5432/)
    ? process.env.DB_HOST.match(/(.*):5432/)[1]
    : process.env.DB_HOST,
  database: process.env.DB_NAME,
  password: process.env.DB_PASS,
  port: 5432,
};

app.get("/", function (req, res) {
  res.send("Hello world!");
});

app.get("/health", async function (_, res) {
  res.sendStatus(200);
});

app.get("/db_healthcheck", async function (_, res) {
  const { Pool } = require("pg");
  const pool = new Pool(PG_CONFIG);
  const text = `
    CREATE TABLE IF NOT EXISTS "users" (
	    "id" SERIAL,
	    "name" VARCHAR(100) NOT NULL,
	    "role" VARCHAR(15) NOT NULL,
	    PRIMARY KEY ("id")
    );`;
  try {
    await pool.query(text);
  } catch (error) {
    console.log("already created");
    console.log(error);
  }

  const d_res = await pool.query("SELECT * FROM users LIMIT 5");
  pool.end();
  return res.send(d_res);
});

app.listen(process.env.PORT || "3000", "0.0.0.0", 10, () => {
  console.log("app is working on `http://localhost:3000/`...");
});