nathantross

Debugging and Exceptions

Agenda

1. Debugging Philosophy and Techniques
2. Basic Errors and Reading an Exception
3. Methods and the Stack, Reading a Backtrace
4. Error Classes, Raising and Rescuing
5. More Debugging Techniques, a Glimpse of Testing

Debugging in the Abstract

nathantross

RSpec Testing

##BDD - Behavior Driven Development #Learing Objectives:

• Understand BDD development flow

• Install and configure RSpec

• Understand basic RSpec blocks: describe, context, it

• Understand how to write RSpec tests

• Understand how to run RSpec tests

• Understand how to make list of attributes and behaviors

nathantross

Object Oriented Design & Programming - exercise

###Quick review:

• What's an object, what's a class?

Classes are a little bit like templates. Usually, you create an instance of a class - an object. Object methods get the job done, for example blend a smoothie.

Sometimes classes have methods too, that means classes can do things without the need to create an object. But for sake of simplicity, let's say we always want to create an instance of a class, an object.

nathantross

require 'sinatra'
require 'sinatra/reloader'

get "/:operator/*" do
	operator = params[:operator].to_s
	n = params[:splat][0].split('/')
	n.map!{ |e| e.to_f }
	
	case operator
	when "add"

nathantross

More Sinatra

Views

Right now, we are serving a "Hello, World!" string to the client. However, this is the web and content sent to clients is usually HTML. Lets create a folder for these HTML files called views.

Let's create an index.html file as follows.

./views/index.html

nathantross

Bootstrap so far

Go to http://getbootstrap.com and download the dist folder.

• Navigate to the dist/css/bootstrap.min.css file.
• Copy and paste it into your app folder under /public/stylesheets/bootstrap.min.css.

Let's create our own responsive grid example. Go to the index

nathantross

#Debugging & Testing

Find the errors in the following

1.)*

My script is loading fine, but separate style sheets aren't working

nathantross

Rails View

• Understand steps to set up rails app.

  *

  Start Sublime

  *

  Edit Gemfile - 'pry'

  *

  Bundle Install

  *

  Edit .gitignore file

  *

  Add Bootstrap

• Understand steps to get rails app running.

  *

  Setup first route

  * Setup first Controller

nathantross

Rails View

• Understand steps to set up rails app.

  *

  Start Sublime

  *

  Edit Gemfile - 'pry'

  *

  Bundle Install

  *

  Edit .gitignore file

  *

  Add Bootstrap

• Understand steps to get rails app running.

  *

  Setup first route

  * Setup first Controller

nathantross

# app/controllers/site_controller.rb

class SiteController < ApplicationController
    
    def index
    end
    
    def contact
    end