April 2012
Intermediate to advanced
294 pages
6h 27m
English
Content preview from Developing Web Applications with Haskell and YesodBecome an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
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Chapter 12. RESTful Content
One of the stories from the early days of the Web is how search engines wiped out entire
websites. When dynamic web sites were still a new concept, developers didn’t appreciate the
difference between a GET and POST request. As a result, they created pages—accessed with the
GET method—that would delete pages. When search
engines started crawling these sites, they could wipe out all the content.
If these web developers had followed the HTTP spec properly, this would not have
happened. A GET request is supposed to cause no side effects
(you know, like wiping out a site). Recently, there has been a move in web development
to properly embrace Representational State Transfer, also known as REST. This chapter
describes the RESTful features in Yesod and how you can use them to create more robust
web applications.
Request Methods
In many web frameworks, you write one handler function per resource. In Yesod, the default is to have a separate handler function for each request method. The two most common request methods you will deal with in creating websites are GET and POST. These are the most well-supported methods in HTML, since they are the only ones supported by web forms. However, when creating RESTful APIs, the other methods are very useful.
Technically speaking, you can create whichever request methods you like, but it is strongly recommended to stick to the ones spelled out in the HTTP spec. The most common of these are:
- GET
Read-only requests. Assuming no other ...
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.