Simplify database connection

[oliverjam]

As I mentioned in this Master Reference issue, the database connection code we've always started students off with is unnecessarily complex.

We can drop almost all the connection string parsing and give it straight to pg:

const { Pool } = require("pg");
require('env2')('./config.env');

const connectionString = process.env.DB_URL;

if (!connectionString) throw new Error("Please set a DB_URL environment variable");

module.exports = new Pool({
  connectionString,
  ssl: !connectionString.includes("localhost")
});

I'm happy to go through all the steps and make the change—it should probably be done for all the workshops this week so the db setup is always consistent.

[astroash]

@oliverjam sounds like a great idea. Do we know how many workshops this is covered in?

[oliverjam]

@astroash sooo many 🙃

I've raised an issue on the initial codealong where we introduce pg. I'll try and do PRs one by one for all the places we have a db_connection.js

[shiryz]

@oliverjam using connectionString shortens the workshop by at least half an hour, we've already tested it before and I'm all in favour of using it.
Like you said so many WSs are built on top of this one and would need to be modified as well...

[samjam48]

This does seem like a great idea @oliverjam

Going through this definitely took a while. also explaining all the object destructuring and assigning added a bunch of time that wasn't needed and mostly forgotten till they get round to it later in the course anyway.

I'm happy dividing the task if you're still interested in doing it?

[samjam48]

Thanks @jema28 for amending the step 3 code. I led the workshop following from the "mentor notes" which weren't amended 🙈
I've updated them to match so that hopefully this mistake doesn't happen again. if someone can accept that change?