Mastering Ruby on Rails: A Beginner's Guide

341 Pages·2022·5.405 MB·English

by  Sufyan Bin Uzayr

Mastering Ruby on Rails
Mastering Computer Science
Series Editor: Sufyan bin Uzayr
Mastering Ruby on Rails: A Beginner’s Guide
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Mastering C#: A Beginner’s Guide
Mohamed Musthafa MC, Divya Sachdeva, and Reza Nafim
Mastering GitHub Pages: A Beginner’s Guide
Sumanna Kaul and Shahryar Raz
Mastering Unity: A Beginner’s Guide
Divya Sachdeva and Aruqqa Khateib
Mastering Unreal Engine: A Beginner’s Guide
Divya Sachdeva and Aruqqa Khateib
For more information about this series, please visit: https://
www.routledge.com/Mastering-Computer-Science/
book-series/MCS
The “Mastering Computer Science” series of books are
authored by the Zeba Academy team members, led by
Sufyan bin Uzayr.
Zeba Academy is an EdTech venture that develops
courses and content for learners primarily in STEM
fields, and offers education consulting to Universities and
Institutions worldwide. For more info, please visit https://
zeba.academy
Mastering Ruby on Rails
A Beginner’s Guide
Edited by Sufyan bin Uzayr
First edition published 2022
by CRC Press
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and by CRC Press
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CRC Press is an imprint of Taylor & Francis Group, LLC
© 2022 Sufyan bin Uzayr
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ISBN: 978-1-032-13509-0 (hbk)
ISBN: 978-1-032-13507-6 (pbk)
ISBN: 978-1-003-22960-5 (ebk)
DOI: 10.1201/9781003229605
Typeset in Minion
by KnowledgeWorks Global Ltd.
Contents
About the Editor, xiii
Chapter 1 ◾ I ntroduction to Ruby on Rails 1
WHAT IS RUBY AND RUBY ON RAILS? 2
MAJOR FEATURES 17
RAILS VS OTHER FRAMEWORKS 28
Ruby on Rails Vs Python 28
Ruby on Rails Vs PHP 29
Ruby on Rails Vs Java 29
Ruby on Rails vs JavaScript 29
Ruby on Rails Vs Node.js 30
Ruby on Rails Vs Ruby 30
Pros and Cons: Ruby 32
Pros 32
Cons 32
Pros and Cons: Ruby on Rails 33
Pros 33
Cons 34
v
vi ◾ Contents
INSTALLATION AND CONFIGURATION OF
RUBY ON RAILS 35
Creating a Sample Blog Application 38
Saying “Hello” in Rails 42
MVC 45
DATABASE MIGRATIONS 46
Chapter 2 ◾ G etting Started with Ruby
on Rails 53
BASIC RUBY ON RAILS SYNTAX 54
Data Type 54
Naming Convention 55
Input and Output 56
Methods 56
Class 57
Model (ActiveRecord) 59
View (ActionView) 59
Controller (ActionController) 59
ADDING FIELDS 61
Generic Search Form 62
Helpers for Generating Field and Form
Elements 63
Checkboxes 64
Radio Buttons 64
Other Helpers of Interest 65
Contents ◾ vii
Dealing with Model Objects 68
The fields_for Helper 69
ADDING VALIDATIONS 70
Skipping Validations 74
Validation Helpers 77
acceptance 78
validates_associated 79
confirmation 79
exclusion 81
format 81
inclusion 82
length 82
numericality 84
presence 85
absence 87
uniqueness 87
validates_with 89
validates_each 91
Common Validation Options 92
allow_nil 92
allow_blank 92
message 93
on 94
Strict Validations 96
viii ◾ Contents
Conditional Validation 97
Using a Proc with :if and :unless 98
Grouping Conditional Validations 98
Combining Validation Conditions 99
GENERATED FILES 101
Chapter 3 ◾ Ruby Data Types 111
STRING 113
Expression Substitution 114
General Delimited Strings 114
Escape Characters 115
Character Encoding 116
String Built-in Methods 116
NUMBERS 125
Integers 126
Floating-Point Numbers 130
Ruby Rational Numbers 136
Ruby Nil Value 137
ARRAYS AND HASHES 139
Array Built-in Methods 141
Hashes 149
Hash Built-in Methods 150
SYMBOLS 155
Chapter 4 ◾ Basics of Language 161
VARIABLES 163
Ruby Variable Naming Conventions 164
Contents ◾ ix
Ruby Global Variables 168
Ruby Instance Variables 169
Ruby Class Variables 171
Ruby Local Variables 172
Ruby Constants 173
Ruby Pseudo-Variables 174
OPERATORS 174
Ruby Arithmetic Operators 175
Ruby Comparison Operators 176
Ruby Assignment Operators 177
Ruby Parallel Assignment 178
Ruby Bitwise Operators 179
Ruby Logical Operators 180
Ruby Ternary Operator 181
Ruby Range Operators 181
Ruby defined? Operators 182
Double Colon “::” Operator 183
Ruby Operators Precedence 184
BLOCKS AND ITERATORS 185
Blocks and Methods 189
BEGIN and END Blocks 189
Iterators 190
Ruby Each Iterator 191
Ruby Collect Iterator 192
Procs 193
Lambdas 195