Agile Web Development with Rails 5.1

486 Pages·2017·6.51 MB·English

by  Sam Ruby

Early praise for Agile Web Development with Rails 5.1
The best book to get started in the Rails world. A comprehensive, coherent, and
concise overview of the Ruby on Rails framework. It treats learning in a gradual
way, creating an application from scratch using the latest technologies.
➤ Luis Miguel Cabezas Granado
Ruby on Rails and PHP developer at Junta de Extremadura (Spain) and PHP
book writer at Anaya Multimedia,
I liked how the book guided me through each step of the tasks. This book gives
a thorough introduction to Rails, and I’d suggest it to anyone who wants to start
development with Rails.
➤ Gábor László Hajba
Software Developer, EBCONT Enterprise Technologies
The book was really pleasant to read; I liked how it creates a foundational under-
standing of Rails with a realistic scenario and then builds upon it for the more
advanced topics.
➤ Alessandro Bahgat
Software Engineer, Google
We've left this page blank to
make the page numbers the
same in the electronic and
paper books.
We tried just leaving it out,
but then people wrote us to
ask about the missing pages.
Anyway, Eddy the Gerbil
wanted to say “hello.”
Agile Web Development with Rails 5.1
Sam Ruby
David Bryant Copeland
with Dave Thomas
The Pragmatic Bookshelf
Raleigh, North Carolina
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Printed in the United States of America.
ISBN-13: 978-1-68050-251-0
Encoded using the finest acid-free high-entropy binary digits.
Book version: P1.0—November 2017
Contents
Foreword to the Rails 5 Edition . . . . . . . . xi
Preface to the Rails 5.1 Edition . . . . . . . . xiii
Acknowledgments . . . . . . . . . . . xv
Introduction . . . . . . . . . . . . xvii
Part I — Getting Started
1. Installing Rails . . . . . . . . . . . . 3
Installing on Cloud9 4
Installing on a Virtual Machine 7
Installing on Windows 9
Installing on Mac OS X 12
Installing on Linux 14
Choosing a Rails Version 16
Setting Up Your Development Environment 16
Rails and Databases 20
2. Instant Gratification . . . . . . . . . . . 23
Creating a New Application 23
Hello, Rails! 26
Linking Pages Together 32
When Things Go Wrong 35
3. The Architecture of Rails Applications . . . . . . 39
Models, Views, and Controllers 39
Rails Model Support 42
Action Pack: The View and Controller 44
4. Introduction to Ruby . . . . . . . . . . 47
Ruby Is an Object-Oriented Language 47
•
Contents vi
Data Types 49
Logic 53
Organizing Structures 56
Marshaling Objects 59
Pulling It All Together 59
Ruby Idioms 60
Part II — Building an Application
5. The Depot Application . . . . . . . . . . 65
Incremental Development 65
What Depot Does 66
Let’s Code 70
6. Task A: Creating the Application . . . . . . . . 71
Iteration A1: Creating the Product Maintenance Application 71
Iteration A2: Making Prettier Listings 78
7. Task B: Validation and Unit Testing . . . . . . . 87
Iteration B1: Validating! 87
Iteration B2: Unit Testing of Models 91
8. Task C: Catalog Display . . . . . . . . . 103
Iteration C1: Creating the Catalog Listing 103
Iteration C2: Adding a Page Layout 107
Iteration C3: Using a Helper to Format the Price 112
Iteration C4: Functional Testing of Controllers 114
Iteration C5: Caching of Partial Results 116
9. Task D: Cart Creation . . . . . . . . . . 121
Iteration D1: Finding a Cart 121
Iteration D2: Connecting Products to Carts 122
Iteration D3: Adding a Button 125
10. Task E: A Smarter Cart . . . . . . . . . . 133
Iteration E1: Creating a Smarter Cart 133
Iteration E2: Handling Errors 138
Iteration E3: Finishing the Cart 143
11. Task F: Add a Dash of Ajax . . . . . . . . . 151
Iteration F1: Moving the Cart 152
Iteration F2: Creating an Ajax-Based Cart 159
•
Contents vii
Iteration F3: Highlighting Changes 164
Iteration F4: Hiding an Empty Cart with a Custom Helper 167
Iteration F5: Broadcasting Updates with Action Cable 169
12. Task G: Check Out! . . . . . . . . . . 175
Iteration G1: Capturing an Order 175
Iteration G2: Atom Feeds 189
13. Task H: Entering Additional Payment Details . . . . 195
Iteration H1: Adding Fields Dynamically to a Form 195
Iteration H2: Testing Our JavaScript Functionality 214
14. Task I: Processing Emails and Payments Efficiently . . . 217
Iteration I1: Sending Confirmation Emails 217
Iteration I2: Connecting to a Slow Payment Processor
with Active Job 225
15. Task J: Logging In . . . . . . . . . . . 235
Iteration J1: Adding Users 235
Iteration J2: Authenticating Users 239
Iteration J3: Limiting Access 245
Iteration J4: Adding a Sidebar, More Administration 247
16. Task K: Internationalization . . . . . . . . 253
Iteration K1: Selecting the Locale 254
Iteration K2: Translating the Storefront 257
Iteration K3: Translating Checkout 265
Iteration K4: Adding a Locale Switcher 276
17. Task L: Deployment and Production . . . . . . 279
Iteration L1: Deploying with Phusion Passenger and MySQL 281
Iteration L2: Deploying Remotely with Capistrano 288
Iteration L3: Checking Up on a Deployed Application 294
Iteration L4: Deploying with Fewer Steps on Heroku 295
18. Depot Retrospective . . . . . . . . . . 301
Rails Concepts 301
Documenting What We’ve Done 304
•
Contents viii
Part III — Rails in Depth
19. Finding Your Way Around Rails . . . . . . . . 307
Where Things Go 307
Naming Conventions 315
20. Active Record . . . . . . . . . . . . 319
Defining Your Data 319
Locating and Traversing Records 324
Creating, Reading, Updating, and Deleting (CRUD) 328
Participating in the Monitoring Process 342
Transactions 348
21. Action Dispatch and Action Controller . . . . . . 353
Dispatching Requests to Controllers 354
Processing of Requests 363
Objects and Operations That Span Requests 375
22. Action View . . . . . . . . . . . . 385
Using Templates 385
Generating Forms 387
Processing Forms 390
Uploading Files to Rails Applications 391
Using Helpers 395
Reducing Maintenance with Layouts and Partials 402
23. Migrations . . . . . . . . . . . . . 411
Creating and Running Migrations 411
Anatomy of a Migration 414
Managing Tables 418
Advanced Migrations 423
When Migrations Go Bad 424
Schema Manipulation Outside Migrations 425
24. Customizing and Extending Rails . . . . . . . 427
Testing with RSpec 427
Creating HTML Templates with Slim 433
Serving CSS via Webpack 435
Customizing Rails in Other Ways 437
Where to Go from Here 438