Test database url

[LawEKS]

Currently your application can only supports a development database.
It is a good idea to supply a test database url to run your tests on.
Otherwise you be deleting any information you add as you are working on the development database

I would do something like this:

// db_connection.js
let DB_URL = process.env.DATABASE_URL;

if (process.env.NODE_ENV === 'test') {
  DB_URL = process.env.TEST_DATABASE_URL;
}

if (!DB_URL) {
  throw new Error('Environment variable DATABASE_URL must be set');
}

const params = url.parse(DB_URL);

# config.env

DATABASE_URL=postgres://admin:doggo@localhost:5432/dogspotting_dev
TEST_DATABASE_URL=postgres://admin:doggo@localhost:5432/dogspotting_test

DB_MAX_CONNECTIONS=4

// package.json

  "scripts": {
    "start": "nodemon server.js",
    "test": "NODE_ENV=test node tests/test.server.js | tap-spec",
    "coverage": "nyc report --reporter=text-lcov > coverage.lcov && codecov"
  },