Jump Start Rails

Jump Start Rails

Andy Hawthorne

Language: English

Pages: 150

ISBN: 0987467425

Format: PDF / Kindle (mobi) / ePub

Jump Start Rails provides you with a fun and yet practical introduction to Rails, an incredibly popular framework that makes it possible to quickly develop incredibly powerful web applications with Ruby. This short book covers Rails 4, the latest version of the framework, and while it's not intended to be a completely comprehensive Rails guide or an in-depth Ruby tutorial, it will quickly get you up to speed with Rails and give you the confidence to start experimenting on your own.

The book is built around a real-life example project: a personal portfolio site. It's a fun and easily understandable project that is used to demonstrate the concepts outlined in the book in a practical way.

This is a clear, approachable and very easy-to-follow book that will get you to to speed with Rails in no time.

jQuery Pocket Reference

Pathologies of Power: Health, Human Rights, and the New War on the Poor

Linux Kernel in a Nutshell

PHP in a Nutshell

JavaServer Faces: Introduction by Example

Merchants of Despair: Radical Environmentalists, Criminal Pseudo-Scientists, and the Fatal Cult of Antihumanism












wanted to add a text field called slug to this table. The purpose of the field would be to hold a friendly URL reference for each record in the table. That's so that we have human-friendly text in our URLs rather than a string of numbers. Let's say I also want a blurb field to contain a short paragraph that provides a description of the page too. There is a way to alter table structures using migrations, even if we've already run the migration. To add another field, we just create another

Next, we'll add this validation rule: validates :slug, presence: true, format: { with: /\A[a-zA-Z]+\z/, ↵message: "Only letters allowed" } This ensures that our slug has a value, and that it only contains letters. Notice that we've the option to add our own (friendlier) error messages. Hang on, though—if our validation is only going to allow letters, and the slug is for our URLs, we'll need to allow hyphens, right? No problem. We can alter the validation rule like this: with: /\A[a-zA-Z-]+\z/

Models are used mostly for setting the rules for interaction with database tables. Normally, you would have one model per database table. Views are HTML files with Ruby embedded to perform tasks for the presentation of data. Views are the user interface — the part of your app with which the user interacts. Controllers are the components that decide how to respond to user requests. They are responsible for coordinating responses too. You can think of them as traffic police directing requests

you want to apply, the default metadata will be used instead. That means you can keep your SEO references consistent throughout the app. Uploads The next bit of functionality that will be useful to add to our app is the ability to upload images. We've done some of the groundwork for this already. If you recall, in the last chapter we added a new form to ActiveAdmin that provides an image upload input field. We also added a new field called image to our posts table in the database. That

If you're on Windows and using Rails Installer, you'll be able to use the terminal app to do the same thing. If you aren't using Rails Installer, there's a guide here to set folder permissions. We've used the recursive switch here because CarrierWave will upload files into sub-directories organized by model and date. Updating the Post Model Now we can add the upload to the posts model. That's done by calling the mount_uploader method. We pass in the name—image—that we used above when

Download sample