Component-Based Rails Applications
Component-Based Rails Applications
Large Domains Under Control
About the Book
As Rails applications grow and mature the help we get from the framework shrinks - to some, it even feels like the framework gets in the way. It doesn't need to be that way! With component-based applications we have a great way to control the complexity of our domain. In areas where Rails alone does not lend much support, we look to proven patterns to create a meaningful support structure for all of our applications.
With this book you will learn
- How to create components with gems and engines.
- How to spot and fix common technical issues
- What refactorings to use to tease out new components
- How to extract your first component from any existing project
- How to apply component-based design together with the hexagonal and DCI architectural patterns
You will hear from others that have taken the journey and how they used components to improve their projects.
As you will learn through this book, components are also a great stepping stones towards micro-service architectures.
The intent of this book goes well beyond Rails: We want you to become a better software engineer. Components are a proven method of software development and all popular programming languages allow the creating of components in some way. The learnings from this book will improve your ability to create maintainable applications in any language!
Table of Contents
- Preface
-
1. Introduction
-
1.1 Component-Based Rails
- 1.1.1 What Is It?
- 1.1.2 History Repeating?
- 1.2 Component-Based Ruby
- 1.3 The Application Continuum
-
1.4 What This Book Does not Cover
- 1.4.1 Ruby and Rails Basics
- 1.4.2 Rails 2
- 1.5 Related Works
- 1.6 Structure of This Book
-
1.1 Component-Based Rails
-
2. Introducing the First Component
- 2.1 How Do I Start Writing a CBRA App?
-
2.2 Plain vs
--full
vs--mountable
Engines - Which Command Line Options Should I Use for Engine Creation?- 2.2.1 Plain Plugin
- 2.2.2 Full Engine
- 2.2.3 Mountable Engine
- 2.3 How do Engine Routes and Engine Mounting Work?
-
2.4 How Do I Handle Migrations Inside of a Component?
- 2.4.1 Installing Engine Migrations With Rake
- 2.4.2 Loading Engine Migrations in Place
- 2.4.3 Known Issues
-
2.5 How Do I Handle Dependencies in My CBRA App?
-
2.5.1 Adding a Different Templating Library:
slim
(Adding a Regular Gem) - 2.5.2 Locking Down Gem Versions
-
2.5.3 Adding the Rating Calculation Library:
trueskill
(Adding the Development Version of a Gem) -
2.5.4 Adding a Different Testing Framework:
rspec-rails
(Adding Development Dependencies)
-
2.5.1 Adding a Different Templating Library:
-
2.6 How Do I Test My Component?
- 2.6.1 ActiveRecord Model Specs
- 2.6.2 Non-ActiveRecord Model Specs
- 2.6.3 Controller Specs
- 2.6.4 Helper Spec
- 2.6.5 View Specs
- 2.6.6 Routing Specs
- 2.6.7 Feature Specs
-
2.7 How Do I Test the Main Application?
- 2.7.1 What to Test in the Main App
- 2.7.2 How to Put Everything Together
- 2.7.3 How to Set Up a Continuous Integration (CI) Server
-
2.8 How Do I Load Component Assets Properly?
- 2.8.1 Production-Ready Assets
- 2.9 How to set up databases with engines?
-
2.10 How Do I Deploy to Production?
- 2.10.1 Deploying to Heroku
- 2.10.2 Deploying to Pivotal Web Services
-
2.11 How Do I Update My Application’s Dependencies?
- 2.11.1 Updating the Bundle in All Components
- 2.11.2 Updating Every Component’s Gem Version
- 2.11.3 Updating Rails
- 2.11.4 Long Running Dependency Updates
- 2.11.5 Listing a Dependency Only Once
-
2.12 How Do I Make it More Clear That This App is Different?
- 2.12.1 Why Would I Want to Change That?
- 2.12.2 How CBRA Can Change How I Present and Perceive My App
- 2.12.3 Making CI and PaaS Work With the New Structure
- 2.12.4 What is Next?
-
3. From One Component to Many Components
-
3.1 Why Would I Ever Add Another Component?
- 3.1.1 Improved Communication
- 3.1.2 Improved Collaboration
- 3.1.3 Improved Creation
- 3.1.4 Improved Maintenance
- 3.1.5 Improved Comprehension
- 3.2 Determining What to Extract - Bottum-up
-
3.3 Refactoring: Extract Domain Gem -
Predictor
-
3.3.1 Fixing Inside-out - Making
AppComponent
Work Again - 3.3.2 Last Step: Ensure That the App Works
- 3.3.3 Summary of Bottom-Up Component Extractions
-
3.3.1 Fixing Inside-out - Making
-
3.4 Determining What to Extract - Top-down
- 3.4.1 Unclear dependency direction
- 3.4.2 Not everything needs the predictor
- 3.4.3 Implications of the first set of extractions
- 3.4.4 Problem with the current solution
- 3.4.5 Reducing needed dependencies
-
3.5 Refactoring: Pulling Up a UI Component -
TeamAdmin
,GameAdmin
,PredictionUI
,WelcomeUI
- 3.5.1 Generate
- 3.5.2 Move
- 3.5.3 Fix, part 1: Reusing test helpers
- 3.5.4 Fix, part 2: Routing issues
- 3.5.5 Fix, part 3: The container application
-
3.6 Refactoring: Pushing Down a Model Component -
Teams
,Games
- 3.6.1 Getting Away With Less
-
3.6.2 Fixing
Teams
’ tests - 3.6.3 Fixing Everything Else
-
3.7 Refactoring: Improve Naming of Component -
AppComponent
toWebUI
-
3.7.1 Whatever Happened to
AppComponent
? - 3.7.2 Refactoring Component Names
- 3.7.3 Refactoring a Component Name Throughout the Application
- 3.7.4 An Even More Mechanical Approach
-
3.7.1 Whatever Happened to
-
3.8 More Component Refactoring Patterns
- 3.8.1 Splitting One Component in Two: Disentangling Unrelated Concepts
- 3.8.2 API Component
- 3.8.3 3rd Party Service Adapter
- 3.8.4 Common functionality component
-
3.1 Why Would I Ever Add Another Component?
-
4. From Ball Of Mud to First Components
- 4.1 Small Steps
-
4.2 One Big Step
- 4.2.1 Prerequisites
- 4.2.2 Script This!
- 4.2.3 A Scripted Refactoring
-
4.2.4 Cleaning Up
persistence
-
4.2.5 Using
persistence
- 4.2.6 Summary
-
5. Component-based Rails in relation to other patterns
-
5.1 Hexagonal Architecture
- 5.1.1 Hexagonal Architecture and CBRA
- 5.1.2 Implementing Hexagonal Rails with CBRA
- 5.1.3 Teasing out an adapter in the frontend
- 5.1.4 A repository for data storage
- 5.1.5 Swappable data storage
- 5.1.6 Summary
-
5.2 Data-Context-Integration (DCI)
- 5.2.1 DCI and CBRA
- 5.2.2 Implementing DCI with CBRA
- 5.2.3 Summary
-
5.1 Hexagonal Architecture
-
6. Case Studies
-
6.1 Using components for good object-oriented design — Ryan Platte
- 6.1.1 About me
- 6.1.2 Without packages, you have a mess
- 6.1.3 A clean way to juggle integrations
- 6.1.4 Approaching the transition gradually
- 6.1.5 Depending only on the domain
- 6.1.6 Shell commands
- 6.1.7 Moving into a new business
- 6.1.8 Our experiences
-
6.2 Stories of Engines — Benjamin Lee Smith
- 6.2.1 Intro
- 6.2.2 Engines Project #1: The from-scratch-rebuild
-
6.3 Using components to deploy parts of a Rails applications — Enrico Teotti
- 6.3.1 About me
- 6.3.2 A straightforward evolving application
- 6.3.3 Let’s join the SOA wagon!
- 6.3.4 Let’s share Engines on a private gemserver!
- 6.3.5 Component based with local gems and Engines
-
6.1 Using components for good object-oriented design — Ryan Platte
- Notes
Authors have earned$9,909,464writing, publishing and selling on Leanpub, earning 80% royalties while saving up to 25 million pounds of CO2 and up to 46,000 trees.
Learn more about writing on Leanpub
The Leanpub 45-day 100% Happiness Guarantee
Within 45 days of purchase you can get a 100% refund on any Leanpub purchase, in two clicks.
See full terms
Free Updates. DRM Free.
If you buy a Leanpub book, you get free updates for as long as the author updates the book! Many authors use Leanpub to publish their books in-progress, while they are writing them. All readers get free updates, regardless of when they bought the book or how much they paid (including free).
Most Leanpub books are available in PDF (for computers), EPUB (for phones and tablets) and MOBI (for Kindle). The formats that a book includes are shown at the top right corner of this page.
Finally, Leanpub books don't have any DRM copy-protection nonsense, so you can easily read them on any supported device.
Learn more about Leanpub's ebook formats and where to read them
Top Books
C++ Best Practices
Jason TurnerLevel up your C++, get the tools working for you, eliminate common problems, and move on to more exciting things!
Continuous Delivery Pipelines
Dave FarleyThis practical handbook provides a step-by-step guide for you to get the best continuous delivery pipeline for your software.
OpenIntro Statistics
David Diez, Christopher Barr, Mine Cetinkaya-Rundel, and OpenIntroA complete foundation for Statistics, also serving as a foundation for Data Science.
Leanpub revenue supports OpenIntro (US-based nonprofit) so we can provide free desk copies to teachers interested in using OpenIntro Statistics in the classroom and expand the project to support free textbooks in other subjects.
More resources: openintro.org.
C++20
Rainer GrimmC++20 is the next big C++ standard after C++11. As C++11 did it, C++20 changes the way we program modern C++. This change is, in particular, due to the big four of C++20: ranges, coroutines, concepts, and modules.
The book is almost daily updated. These incremental updates ease my interaction with the proofreaders.
Atomic Kotlin
Bruce Eckel and Svetlana IsakovaFor both beginning and experienced programmers! From the author of the multi-award-winning Thinking in C++ and Thinking in Java together with a member of the Kotlin language team comes a book that breaks the concepts into small, easy-to-digest "atoms," along with exercises supported by hints and solutions directly inside IntelliJ IDEA!
Introductory Statistics with Randomization and Simulation
Mine Cetinkaya-Rundel, Christopher Barr, OpenIntro, and David DiezA complete foundation for Statistics, also serving as a foundation for Data Science, that introduces inference using randomization and simulation while covering traditional methods.
Leanpub revenue supports OpenIntro, so we can provide free desk copies to teachers interested in using our books in the classroom.
More resources: openintro.org.
Ansible for DevOps
Jeff GeerlingAnsible is a simple, but powerful, server and configuration management tool. Learn to use Ansible effectively, whether you manage one server—or thousands.
Java OOP Done Right
Alan MellorObject Oriented Programming is still a great way to create clean, maintainable code. But only if you use it right.
This book gives you 25 years of OO best practice, ready to use.
You'll learn to design objects behaviour-first, use TDD to help, then confidently apply Design Patterns, SOLID principles and Refactoring to make clean, crafted code.
Introducing EventStorming
Alberto BrandoliniThe deepest tutorial and explanation about EventStorming, straight from the inventor.
Discrete Mathematics for Computer Science
Alexander Shen, Alexander S. Kulikov, Vladimir Podolskii, and Aleksandr GolovnevThis book supplements the DM for CS Specialization at Coursera and contains many interactive puzzles, autograded quizzes, and code snippets. They are intended to help you to discover important ideas in discrete mathematics on your own. By purchasing the book, you will get all updates of the book free of charge when they are released.
Top Bundles
- #1
Software Architecture for Developers: Volumes 1 & 2 - Technical leadership and communication
2 Books
"Software Architecture for Developers" is a practical and pragmatic guide to modern, lightweight software architecture, specifically aimed at developers. You'll learn:The essence of software architecture.Why the software architecture role should include coding, coaching and collaboration.The things that you really need to think about before... - #2
CCIE Service Provider Ultimate Study Bundle
2 Books
Piotr Jablonski, Lukasz Bromirski, and Nick Russo have joined forces to deliver the only CCIE Service Provider training resource you'll ever need. This bundle contains a detailed and challenging collection of workbook labs, plus an extensively detailed technical reference guide. All of us have earned the CCIE Service Provider certification... - #3
Cisco CCNA 200-301 Complet
4 Books
Ce lot comprend les quatre volumes du guide préparation à l'examen de certification Cisco CCNA 200-301. - #4
Modern C++ by Nicolai Josuttis
2 Books
- #5
CCDE Practical Studies (All labs)
3 Books
CCDE lab - #6
"The C++ Standard Library" and "Concurrency with Modern C++"
2 Books
Get my books "The C++ Standard Library" and "Concurrency with Modern C++" in a bundle. The first book gives you the details you should know about the C++ standard library; the second one dives deeper into concurrency with modern C++. In sum, you get more than 600 pages full of modern C++ and about 250 source files presenting the standard library... - #7
Mastering Containers
2 Books
Docker and Kubernetes are taking the world by storm! These books will get you up-to-speed fast! Docker Deep Dive is over 400 pages long, and covers all objectives on the Docker Certified Associate exam.The Kubernetes Book includes everything you need to get up and running with Kubernetes! - #8
Modern Management Made Easy
3 Books
Read all three Modern Management Made Easy books. Learn to manage yourself, lead and serve others, and lead the organization. - #9
The Future of Digital Health
6 Books
We put together the most popular books from The Medical Futurist to provide a clear picture about the major trends shaping the future of medicine and healthcare. Digital health technologies, artificial intelligence, the future of 20 medical specialties, big pharma, data privacy and how technology giants such as Amazon or Google want to conquer... - #10
Django for Beginners/APIs/Professionals
3 Books