const express = require("express");

const databaseConfig= {
  "host": "localhost",
  "port": 5432,
  "database": "library_app",
  "user": "postgres"
};

const pgp = require("pg-promise")({});
const db = pgp(databaseConfig);

const app = express();
const port = 5000;

app.listen(port, (err) => {
  console.log(`running server on port: ${port}`);
});

const db = pgp(connection);

const initOptions = {
    // global event notification;
    error: (error, e) => {
        if (e.cn) {
            // A connection-related error;
            //
            // Connections are reported back with the password hashed,
            // for safe errors logging, without exposing passwords.
            console.log('CN:', e.cn);
            console.log('EVENT:', error.message || error);
        }
    }
};

const pgp = require('pg-promise')(initOptions);

// using an invalid connection string:
const db = pgp('postgresql://userName:password@host:port/database');

db.connect()
    .then(obj => {
        obj.done(); // success, release the connection;
    })
    .catch(error => {
        console.log('ERROR:', error.message || error);
    });

db.proc('version')
    .then(data => {
        // SUCCESS
        // data.version =
        // 'PostgreSQL 9.5.1, compiled by Visual C++ build 1800, 64-bit'
    })
    .catch(error => {
        // connection-related error
    });