Getting Started with Rails 1 Guide Assumptions This guide is designed for beginners who want to get started with a Rails application from scratch. It does not assume that you have any prior experience with Rails. Rails is a web application framework running on the Ruby programming language. If you have no prior experience with Ruby, you will find a very steep learning curve diving straight into Rails. Be aware that some resources, while still excellent, cover versions of Ruby as old as 1.6, and commonly 1.8, and will not include some syntax that you will see in day-to-day development with Rails. 2 What is Rails? Rails is a web application development framework written in the Ruby programming language. Rails is opinionated software. The Rails philosophy includes two major guiding principles: Don't Repeat Yourself: DRY is a principle of software development which states that "Every piece of knowledge must have a single, unambiguous, authoritative representation within a system." 3 Creating a New Rails Project 9 Security
Model–view–controller Model–view–controller (MVC) is a software pattern for implementing user interfaces. It divides a given software application into three interconnected parts, so as to separate internal representations of information from the ways that information is presented to or accepted from the user.[1][2] The central component, the model, consists of application data, business rules, logic and functions. A view can be any output representation of information, such as a chart or a diagram. Multiple views of the same information are possible, such as a bar chart for management and a tabular view for accountants. The third part, the controller, accepts input and converts it to commands for the model or view.[3] Component interactions[edit] A typical collaboration of the MVC components In addition to dividing the application into three kinds of components, the Model–view–controller (MVC) design defines the interactions between them.[4] Use in web applications[edit] History[edit] See also[edit]
A Quick (and Hopefully Painless) Ride Through Ruby (with Cartoon Foxes) :: Why's (Poignant) Guide to Ruby Yeah, these are the two. My asthma’s kickin’ in so I’ve got to go take a puff of medicated air just now. Be with you in a moment. I’m told that this chapter is best accompanied by a rag. Indeed, we’ll be racing through the whole language. 1. My conscience won’t let me call Ruby a computer language. But what do you call the language when your brain begins to think in that language? We can no longer truthfully call it a computer language. Read the following aloud to yourself. 5.times { print "Odelay!" In English sentences, punctuation (such as periods, exclamations, parentheses) are silent. Which is exactly what this small Ruby program does. exit unless "restaurant".include? Here we’re doing a basic reality check. Ever seen a programming language use question marks so effectively? ['toast', 'cheese', 'wine'].each { |food| print food.capitalize } While this bit of code is less readable and sentence-like than the previous examples, I’d still encourage you to read it aloud. 2. Variables Numbers
When NoSQL Databases Are — Yes — Good For You And Your Company The proliferation of non-relational databases in the tech sector these days could lead you to think that these data management tools (also known as NoSQL databases) are eventually going to make traditional relational databases extinct. Not so. Each of these database types is best suited for very different types of workloads, and that's going to prevent either one from tromping the other into the dust. In this two-part series, I'll examine the capabilities of both NoSQL and relational databases to help you make the right decisions for your organization. "NoSQL"? Right off the bat, NoSQL databases are unique because they are usually independent from Structured Query Language (SQL) found in relational databases. See also: Relational Databases Aren't Dead—Heck, They're Not Even Sleeping NoSQL databases are designed to excel in speed and volume. Go Big Or Go Home Easier scalability is the first aspect highlighted by Wiederhold. There's No Need To Fear Objects Of Desire Downtime?
Don't repeat yourself Applying DRY[edit] DRY vs WET solutions[edit] Violations of DRY are typically referred to as WET solutions, which is commonly taken to stand for either "write everything twice" or "we enjoy typing".[2][3] See also[edit] References[edit] External links[edit] Getting a Git Repository You can get a Git project using two main approaches. The first takes an existing project or directory and imports it into Git. The second clones an existing Git repository from another server. Initializing a Repository in an Existing Directory If you’re starting to track an existing project in Git, you need to go to the project’s directory and type $ git init This creates a new subdirectory named .git that contains all of your necessary repository files — a Git repository skeleton. If you want to start version-controlling existing files (as opposed to an empty directory), you should probably begin tracking those files and do an initial commit. $ git add *.c $ git add README $ git commit -m 'initial project version' We’ll go over what these commands do in just a minute. Cloning an Existing Repository If you want to get a copy of an existing Git repository — for example, a project you’d like to contribute to — the command you need is git clone. You clone a repository with git clone [url].
Home Mongoid (pronounced mann-goyd) is an Object-Document-Mapper (ODM) for MongoDB written in Ruby. It was conceived in August, 2009 during a whiskey-induced evening at the infamous Oasis in Florida, USA by Durran Jordan. The philosophy of Mongoid is to provide a familiar API to Ruby developers who have been using Active Record or Data Mapper, while leveraging the power of MongoDB's schemaless and performant document-based design, dynamic queries, and atomic modifier operations. This is the site for Mongoid 3 documentation, along with Origin and Moped. If you want the Mongoid 2 docs, please go here. class Artist include Mongoid::Document field :name, type: String embeds_many :instrumentsend class Instrument include Mongoid::Document field :name, type: String embedded_in :artistend syd = Artist.where(name: "Syd Vicious").between(age: 18..25).first syd.instruments.create(name: "Bass") syd.with(database: "bands", session: "backup").save!
Convention over configuration Convention over configuration (also known as coding by convention) is a software design paradigm which seeks to decrease the number of decisions that developers need to make, gaining simplicity, but not necessarily losing flexibility. The phrase essentially means a developer only needs to specify unconventional aspects of the application. For example, if there's a class Sale in the model, the corresponding table in the database is called “sales” by default. It is only if one deviates from this convention, such as calling the table “sale”, that one needs to write code regarding these names. When the convention implemented by the tool matches the desired behavior, it behaves as expected without having to write configuration files. Motivation[edit] Some frameworks need multiple configuration files, each with many settings. Usage[edit] The Maven software tool auto-generated this directory structure for a Java project. Many modern frameworks use a convention over configuration approach.
Home Active record pattern This pattern is commonly used by object persistence tools, and in object-relational mapping (ORM). Typically, foreign key relationships will be exposed as an object instance of the appropriate type via a property. Implementations[edit] Implementations of the concept can be found in various frameworks for many programming environments. part = new Part() part.name = "Sample part" part.price = 123.45 part.save() will create a new row in the parts table with the given values, and is roughly equivalent to the SQL command INSERT INTO parts (name, price) VALUES ('Sample part', 123.45); Conversely, the class can be used to query the database: b = Part.find_first("name", "gearbox") This will find a new Part object based on the first matching row from the parts table whose name column has the value "gearbox". SELECT * FROM parts WHERE name = 'gearbox' LIMIT 1; -- MySQL or PostgreSQL ColdFusion[edit] ColdFusion has an open source implementation of the Active Record pattern. PHP[edit] Ruby[edit] Java[edit]