- Foreword to the First Edition
- Acknowledgments
- About the Author
- From Zero to Deploy
- Development Environments
- Ruby RubyGems Rails and Git
- The First Application
- rails server
- Model-view-controller MVC
- Version Control with Git
- What Good Does Git Do You
- GitHub
- Branch Edit Commit Merge
- Deploying
- Heroku Setup
- Conclusion
- A Demo App
- Planning the Application
- Modeling Demo Users
- Modeling Demo Microposts
- The Users Resource
- A User Tour
- MVC in Action
- Weaknesses of this Users Resource
- The Microposts Resource
- A Micropost Microtour
- Putting the micro in Microposts
- A User has many Microposts
- Inheritance Hierarchies
- Deploying the Demo App
- Conclusion
- Static Page
- Mostly Static Pages
- Truly Static Pages
- Static Pages with Rails
- Our First Tests
- Test-driven Development
- Adding a Page
- Testing a Title Change
- Passing Title Tests
- Embedded Ruby
- Eliminating Duplication with Layouts
- Conclusion
- Advanced Setup
- Eliminating bundle exec
- Automated Tests with Guard
- Speeding up Tests with Spork
- Tests inside Sublime Text
- Rails-Flavored Ruby
- Strings and Methods
- Objects and Message Passing
- Method Definitions
- Other Data Structures
- Blocks
- Hashes and Symbols
- CSS revisited
- Ruby Classes-Constructors
- Class Inheritance
- Modifying Built-in Classes -A Controller Class
- A User Class
- Conclusion-Exercises
- Adding Some Structure
- Site Navigation
- Bootstrap and Custom CSS
- Partials
- Sass and the Asset Pipeline
- Syntactically Awesome Stylesheets
- Layout Links
- Route Tests
- Rails Routes
- Named Routes
- Pretty RSpec
- User Signup A First Step
- Signup URI
- Conclusion-Exercises
- Modeling Users
- User Model
- Database Migrations
- The Model File
- Creating User Objects
- Finding User Objects
- Updating User Objects
- User Validations
- Validating Presence
- Length Validation-Format Validation
- Uniqueness Validation
- Adding a Secure Password
- An Encrypted Password
- Password and Confirmation
- User Authentication
- User Has Secure Password
- Creating a User
- Conclusion-Exercises
- Showing Users
- Debug and Rails Environments
- A Users Resource
- Testing the User Show Page with Factories
- A Gravatar Image and a Sidebar
- Signup Form
- Tests for User Signup
- Using form for
- The Form HTML
- Signup Failure
- Signup Error Messages
- The Finished Signup Form
- The Flash
- Deploying to Production with SSL
- Conclusion-Exercises
- Sessions and Signin Failure
- Sessions Controller
- Signin Tests
- Signin Form
- Reviewing Form Submission
- Rendering with a Flash Message
- Signin Success
- Remember Me
- A Working sign in Method
- Current User
- Changing the Layout Links
- Signin upon Signup
- Signing Out
- Introduction to Cucumber Optional
- Installation and Setup
- Features and Steps
- Counterpoint RSpec Custom Matchers
- Conclusion-Exercises
- Updating Users
- Edit Form
- Unsuccessful Edits
- Successful Edits
- Authorization
- Requiring Signed-in Users
- Requiring the Right User
- Friendly Forwarding
- Showing All Users
- User Index
- Sample Users
- Pagination
- Partial Refactoring
- Deleting Users-Administrative Users
- The destroy Action
- Conclusion-Exercises
- A Micropost Model
- The Basic Model
- Accessible Attributes and the First Validation
- User Micropost Associations
- Micropost Refinements
- Content Validations
- Showing Microposts
- Augmenting the User Show Page
- Sample Microposts
- Manipulating Microposts
- Access Control
- Creating Microposts
- A Proto-feed
- Destroying Microposts
- Conclusion-Exercises
- Following Users
- The Relationship Model
- A Problem with the Data Model and a Solution
- User Relationship Associations
- Validations
- Followed users
- Followers
- Sample Following Data
- Stats and a Follow Form
- Following and Followers Pages
- A Working Follow Button the Standard Way
- A Working Follow Button with Ajax
- Making the output of find readable in shell
- CRUD Operation-Create
- The Status Feed
- Motivation and Strategy
- A First Feed Implementation
- Subselects
- The New Status Feed
- Conclusion
- Exercises
Ruby On Rails Lesson
of this, take a look at the file db/schema.rb, which should now include a line like this:
Unfortunately, there’s one more change we need to make to be assured of email uniqueness, which is to make sure that the email address is all lowercase before it gets saved to the database. The reason is that not all database adapters use case-sensitive indices.15 The way to do this is with a callback, which is a method that gets invoked at a particular point in the lifetime of an Active Record object (see the Rails API entry on callbacks). In the present case, we’ll use a before_save callback to force Rails to downcase the email attribute before saving the user to the database, as shown in Listing 6.23.
The code in Listing 6.23 passes a block to the before_save callback and sets the user’s email address to a lowercase version of its current value using the downcase string method. This code is a little advanced, and at this point I suggest you simply trust that it works; if you’re skeptical, comment out the uniqueness validation from Listing 6.19 and try to create users with identical email addresses to see the error that results. (We’ll see this technique again in Section 8.2.1.)
Now the Alice scenario above will work fine: The database will save a user record based on the first request and will reject the second save for violating the uniqueness constraint. (An error will appear in the Rails log, but that doesn’t do any harm. You can actually catch the ActiveRecord::StatementInvalid exception that gets raised—see Insoshi for an example—but in this tutorial we won’t bother with this step.) Adding this index on the email attribute accomplishes a second goal, alluded to briefly in Section 6.1.4: It fixes an efficiency problem in find_by_email (Box 6.2).
Pooja Negi
Skills Ruby On Rails
Qualifications :- High School - SSN high school, College/University - HNBGU, College/University - SRHU,Location :-Ranipokhari,Rishikesh,Uttarakhand,India
Description:- Student
Explore