[SOLVED] database WDE-Slides-09.pptx

WDE-Slides-09.pptx

Web System Development with
Ruby on Rails

Day 9(24/Nov/)
The System Design for

Mini Twitter

Todays Topics
We have learned the Web Application

System development using Ruby on Rails.
We have almost covered the basic elements

of the web application through these 8
course days, (and we have checked so
basic things that you might have felt
boring.)

Today, we step in to the new topics, to

create our own Twitter.

TDD continued
p TDD stands for Test Driven Development

p Method, and the environment.

pOne thing we should learn the most,

when we use Ruby on Rails environment.
p On rails, it is so easy to use.

pWe can obtain the highly-proved source
codes, also.

phttp://guides.rubyonrails.org/testing.html

Procedure of TDD
pCreate Test Environment First.

P304, Kiso Ruby on Rails, Impress Japan, 2007

Test Driven Development
Write the test first.
The test script itself could be a program

document.
That environment is RSpec.
We write the document, at the same time,

we write the test script.

4 steps to introduce Test
p Step 1: Write Test

n Make Specification Clear, and write Test according to how it
should work.

p Step 2: Confirm it fails before writing program.

n Prepare Test Script and execute test to prove it works before
writing programs.(Debug the test script.)

p Step 3: Coding

n So that the program passes the test

p Step 4: Refactoring

n Keep it passes the test, and clean the source code.

Test Data Platform
First we write the rspec document, and

then, give the test data which should be
both accepted by the system, and rejected
by the system.

Factory Girl is the environment to generate

such test data.

WEB input simulation
Sometime, the end user may type the

system controls in the way the systems
designer merely imaged.

We cannot write the test specification in the
way we never imagined, but at least we
can write the test script that covers the
area we can imagine.

Capybara is such WEB users behaviors
simulating tool. Now we can automatically
perform the loop back test.

Summary of First Semester
In the introduction (first semester), we have

learnt;
(1)MVC (Model, View, Control) structure
(2)HTML and CSS stylesheets
(3)SQL, the database Manipulation

Language
(4)Ruby language and Grammar
(5)Rails environment
(6)RSpec introduction

Rough Sketch of the Data Flow
In the second semester, the

students are required to
know what we should do
in each part of the
system.

WEB Browser

WEB Server

WEB Application

Database

HTML

1

4

2

4

3

3

To go further
For the practical introduction of the WEB

system, test is necessary to secure the
system performance.

If you are interested in using ruby on rails

as a method to develop the WEB system, I
recommend to try RSpec, Factory Girl,
Capybara, Guard, and such testing
environments.

Our final trial:Twitter!
We introduce My Twitter.

Step 1: Give the project name.
Weibo? Fine!
Well, I put the name Chirpy.

To start with a new project
First, close all the project!

Create a new project
Now, create a new project of Rails.

Before you go through next slide..
Make sure your Linux virtual machine is

connected to the internet.
bundle install command will access to the

rubys web site.
Make sure that your network adaptor is

NAT, and SELinux(system-config-
securityleve-tui) is disabled, and firewall is
enabled.

Project name
Give your favorite project name, then finish

to create the new project.

Add three gems
Open Gemfile, add gem devise, and

uncomment the line:
gem therubyracer, :platforms => :ruby

Add Testing environment
Also add the following gems in Gemfile;
group :test, :development do
gem rspec-rails
gem factory_girl_rails
gem capybara
gem database_cleaner
end

Bundle again
Change directory to the project root, and

then type
bundle install

Check the gems version
Type
gem list devise

to check the gems installation.
This gem is for the login authentication

Design the main table
For my case, Twitter <= Chirpy, and tweet is chirp.So it should have user_id: records who chirped : integer chirp: the message : string photo: image : binary file_name: attached file name : string file_type: attached file type : string chirped_at : time of chirping : timestampAdditional Hint for your own designWe have added the Category to memo. By arranging this field, you may be able to create the Group Tweet twitter. Many to Many: User to User relation table;can be the Follower/Followed control.Think and image your target system; and design the attributes of the table.Create the first tableScaffold the first main table: (type the following in one line) rails generate scaffold chirp user_id:integer chirp:string photo:binary file_name:string file_type:string chirped_at:timestamp Check the migration file, and then migrate;rake db:migrate Another hit of development tacticsRuby on rails environment allows you to scrap and build quite easily.So, change the project name and try to generate the system, until you were satisfied with the system design. Add login authentificationNext step is to add the authentication. We use devise, and we follow the same procedure we introduced last week. Install Devise to the projectType the following command,rails generate devise:install to install devise to your project, at the project root directory.Read the message from the system carefully===============================================================================Some setup you must do manually if you haven’t yet:1. Ensure you have defined default url options in your environments files. Here is an example of default_url_options appropriate for a development environment in config/environments/development.rb: config.action_mailer.default_url_options = { :host => localhost:3000 }

In production, :host should be set to the actual host of your application.

2. Ensure you have defined root_url to *something* in your config/routes.rb.
For example:

root :to => home#index

3. Ensure you have flash messages in app/views/layouts/application.html.erb.
For example:

<%= notice %>

<%= alert %>

4. If you are deploying on Heroku with Rails 3.2 only, you may want to set:

config.assets.initialize_on_precompile = false

On config/application.rb forcing your application to not access the DB
or load models when precompiling your assets.

5. You can copy Devise views (for customization) to your app by running:

rails g devise:views

===============================================================================

3 steps to use devise
1. Ensure you have defined default url

options in your your environments files.
cancels if it causes an error!

2. Ensure you have defined root_url to
*something* in your config/routes.rb.

3. Ensure you have flash messages in app/
views/layouts/application.html.erb.

4. If you are deploying Rails 3.1 on Heroku,

you may want to set: (it does not meet
this condition.)

Set the Login Default Screen(Step 2)
p We set the Login Default Screen to the welcome

screen, which we had created in the last page.
First, we modify

(project name)/config/routes.rb
n Uncomment the line around line #58, to activate, and

modify to lead toe memos#index
root :to => chirps#index

Use your table name for chirps!

Add two lines for login result
message display (Step 3)
p Modify
(project)/app/views/layouts/application.html.erb

p Add the following two lines before <%= yield %>

<%= notice %>

<%= alert %>

View for devise
pHere we generate views for devise. Type

rails generate devise:views

Note
For my case, despite of the explanation

generated when we installed devise as is
shown in the above, the generate
devise:views command caused an error.
In case you faced with the same error,
remove the following line;

config.action_mailer.default_url_options = { :host => localhost:3000 }

User model
User model for authentication could be used to

register the user.
So, this can contain the handle name, real name,

and such.Add the necessary attributes for it.If
you think you do not need to keep the real name
for your system, use the following sample.

rails generate scaffold user email:string handle_name:string

Use user table for authentication
Generate devise to manage the login

authentication for users table
rails generate devise user

Modify migration file
Remove the following line
t.string
in the file:
db/migrate/

2015xxxx_add_devise_to_users.rb

Check migration file, and migrate
Type
rake db:migrate

Authentication Path/Redirection
Modify config/routes.rb, add one line under

the following line.
devise_for :users

get chirps, :to => chirps#index, :as => :user_root

For other controllers
pAdd authentication request as a

before_action, in chirps_controller.rb

before_action :authenticate_user!, only: [:index, :show, :new,
:create, :edit, :destroy, :update, :photo]

Sign out procedure
To destroy the signed-in session, add the following

lines in index.html.erb

<% if current_user %>

<% end %>

Give Users information to a chirp
If we try to add new Chirp,
User : should be given from current_user!

So, add one line in new method in

chirps_controller.rb;
@chirp.user_id = current_user.id

Relationship between user and chirp
Set relationship between users table and chiprs

table in models folder.
Set

belongs_to :user
to chirps, and set

has_many :chirps
to users.Also, add

:user to chirp_params
in chirps_controller.rb.

Modify _form and index.
So that we could see the users email (who

write a chirp,) and accept the longer chirp,
modify _form.html.erb.

We do not need to accept file_name,
file_type, and chirped_at fields from the
screen, so remove them.

Also, modify the :photo field to file_field.

_form.html.erb

_form.html.erb

Input screen now

Now design your own
Some other features are not installed yet.
(1) Image display
(2) Menu bar, footer and such
(3) Multi-lingual (Internationalization)

As for the above, you could see the details

in the previous lecture slides, so I do not
include in todays lecture slides.

Current limitation
We can not record the handle_name of

users table, and edit it.
Next week, we are going to add the above

features, and add the follow/followed
table.

The presentation
We will have the presentation of your memos WEB

page or the twitter system, on 14/January/2016.
Add your original functions to the memos WEB page

or the twitter, and show the system in the class,
(Approx. 2 to 3 minutes per person.) Scored as
the final report.

Before that, you are required to have presentation
on the Design Specifications of your Web
Application/Your Twitter next week!

Describe the test design of the Twitter System;

Registration of Face
The Goal of the project is just like below;

Search tweets
Search tweets with key word;

And register your friends to follow
Search friends with email address or handle

name, and follow your friends;

What to present?
Describe your specs, of your twitter, or

your enhanced memopad, in the language
of RSpec/Capybara/Factory Girls.

Test descriptions are not required.
Simply, specs are enough, just like the next

page.

User login description sample;
describe GET/login do

context with unauthorized access do
it gets a not authorized notification do
end
end

end

http://betterspecs.org/#presentations

This is the expected content of your report.

How to describe test
See the materials of the last week lecture.
Also the following pages;

http://betterspecs.org/

Next week, my sample description

materials(lecture slides) will not be
uploaded, before your presentation.