check how to connect to Postgres on node.js with heroku https://node-postgres.com/features/connecting

difference between client and Pool https://stackoverflow.com/questions/48751505/how-can-i-choose-between-client-or-pool-for-node-postgres

learn basic syntax of postgres * syntax \q | Exit psql connection \c | Connect to a new database \dt | List all tables \du | List all roles \list | List databases

  * stop using superuser and create user me
  ```bash
  postgres=# CREATE ROLE me WITH LOGIN PASSWORD 'password';
  postgres=# ALTER ROLE me CREATEDB;
  postgres= \du
          me          | Create DB                           | {}
          postgres    | Superuser, Create role, Create DB   | {}
  ```
  * use 'me' user
  ```bash
  psql -d postgres -U me
  ```
  https://blog.logrocket.com/setting-up-a-restful-api-with-node-js-and-postgresql-d96d6fc892d8/

re-organized the repo with MVC * create models and routes * move routing functions into the routes directory

learn about authentication https://github.com/Createdd/Writing/blob/master/2017/articles/AuthenticationIntro.md#insert-data-into-mongodb

understand SHA256 = hash([password] + [salt]) https://en.wikipedia.org/wiki/Salt_(cryptography)#targetText=In%20cryptography%2C%20a%20salt%20is,to%20safeguard%20passwords%20in%20storage.&targetText=A%20salt%20is%20one%20of,randomly%20generated%20for%20each%20password.

insert a sample user insert into users (email, username, password, created_on) values('[email protected]', 'kitaa', 'kitaa', current_timestamp);

handles environment variables How to use custom environment variables in Node Create an .env file. The file should be placed in the root of your project Install the dotenv library: npm install dotenv. Require dotenv as early as possible (e.g. in app.js): require('dotenv').config({path: __dirname + '/.env'}). Wherever you need to use environment variables (e.g. in GitLab, in Jenkins, in Heroku, …) you need to add your environment variables. The way depends on the platform but it is usually easy to do. Optional: create a function which runs at startup of your server. It should check whether all the required environment variables are set and throw an error otherwise. from https://itnext.io/how-to-use-environment-variables-in-node-js-cb2ef0e9574a

drop marker to google map https://gist.github.com/SamSamskies/6033264