Ruby PostgreSQL App

Getting Started

To get started, make sure you have PostgreSQL and Ruby installed on your local machine.

If you haven't already, download and install (following instructions pertaining to your system):

PostgreSQL: https://www.postgresql.org/download/

Ruby: https://www.ruby-lang.org/en/downloads/

Installing Rails

$ gem install rails

Creating a new Rails app using PostgreSQL

$ rails new <your-app-name-here> -d postgresql
  ...
$ cd <your-app-name-here>

Setup the database

On Linux enter this in your terminal:

$ sudo -u postgres createuser --superuser <local_dev_username>

Edit config/database.yml to look similar to this:

default: &default
  adapter: postgresql
  encoding: unicode
  pool: 5

development:
  <<: *default
  database: your-app-name-here_development
  username: <local_dev_username>

test:
  <<: *default
  database: your-app-name-here_test
  username: <local_dev_username>

production:
  <<: *default
  database: your-app-name-here_production
  username: <deploy-username>

Again, in the terminal enter:

$ bin/rails db:setup
$ bin/rails db:migrate

On Windows replace bin/ with ruby bin\ anywhere it is used:

$ ruby bin\rails db:setup
$ ruby bin\rails db:migrate

Start the app

In your terminal:

$ bin/rails server // this ensure the app runs on the version of rails it was initialized with

Or, a shortcut:

$ bin/rails s

Then go to http://localhost:3000/ in your browser to see the rails welcome page.

Create Rails Resources

First, stop the server by pressing ctrl+c.

Then, generate your resource:

$ bin/rails generate scaffold Import import_name:string

A migration file will be generated in db/migrate that will look like this:

class CreateImports < ActiveRecord::Migration[5.2]
  def change
    create_table :imports do |t|
      t.string :import_name

      t.timestamps
    end
  end
end

Edit it to look like this:

class CreateImports < ActiveRecord::Migration[5.2]
  def change
    create_table :imports do |t|
      t.string :import_name, null: false
      t.index ["import_name"], name: "imports_import_name_key", unique: true

      t.timestamps
    end
  end
end

Then, back in the terminal:

$ bin/rails db:migrate // needs to be run everytime you generate a scaffold, model, or migration

Start the app again:

$ bin/rails s

Then navigate to http://localhost:3000/imports in your browser.

You can start creating, reading, updating, and deleting imports. Your data will be saved to PostgreSQL.