Getting Started

There are two ways to get started with a Rails application. You can generate a brand new application from scratch, or you can start with code that someone else has written.

Generating a New Rails Application

We use the rails new command to generate a new application:

~/code$ rails new myapp

Always start in the ~/code folder when you run this command, and of course you'll probably want something different than myapp but that's what we'll use in this example. A new subfolder named myapp (or whatever you chose) will be created, and inside of that subfolder will be the skeleton of a brand new web application.

To start working with your new application, change your current directory to be the new subfolder:

Always change your current directory after rails new.

~/code$ cd myapp

You can now start editing the code by simply opening the ~/code/myapp folder in Atom.

Finally, let's "run" the website by starting the "server":

~/code/myapp$ rails server

Now you can use localhost:3000 in your browser to try out your website as you develop.

IMPORTANT: Press CTRL-C when you want to stop the server.

Using an Existing Application

Sometimes you'll be asked to get a copy of an application that's already been generated, usually from GitHub. Imagine that we've downloaded the code for a ride-sharing application named NuLyft and saved it in a folder named ~/code/nulyft. Before we can start working with it, we need to open our command prompt to that directory, and then run the bundle install command:

~/code$ cd ~/code/nulyft
~/code/nulyft$ bundle install

It may take a couple minutes for the bundle install command to do its work. If all goes well, you'll see the words "Bundle complete!" near the end.