An Intro to the WordPress JSON API

WordPress JSON API

Intro

Wil Brown@LimeCanvas

www.limecanvas.com

What is JSON?

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Java Script Object Notation

Lightweight data exchange format akin to XML

Easy for humans and machines to read & write

JSON Simple Example

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{ "first": "Bob", "last": "Bobbley", "sex": "M", "interests": ["Particle Physics", " Beer", "Hacking" ] };

JSON Nested Example

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{

"first": "Bob", "last": "Bobbley", "sex": "M", "interests": [" Particle Physics", " Beer", "Hacking" ] "favourites" : { "colour" : "Purple", "food" : "Pizza" }};

What Is An API?

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Application Programming Interface

A set of functions that allow you to interact with the underlying application.– Read data– Write data– Ask to perform a task

WordPress API Examples

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get_blog_info( ‘name’ )Returns the name of the blog from General Settings

the_content()Returns the post content inside the WordPress loop. Used in most theme templates.

Why The Need?

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1st use of WordPress = Blogging platform2003-2008 (ish)

2nd use of WordPress = CMS (Content Management System)

2008 – 2013 (ish)

3rd use of WordPress = Application Framework2013/14+

Application Framework?

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Not a blog. Not a CMS.

It is WordPress being used as the back-end “system” that other “web” applications can be built upon.

Web apps need to:– get data– send data– ask framework to perform tasks (remember slide 4)– validate who’s asking (WordPress security)

What’s the Difference?

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Traditionally web apps were/are WordPress sites

Now, web apps can be written in anything– Node.js– .net– HMTL/PHP (Laravel)

..while using WordPress as the back-end data store and API.

JSON API – Two Modes

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Operates in two modes: implicit and explicit.

• Implicit mode is triggered by setting the json query var to a non-empty value on any WordPress page. The content that would normally appear on that page is returned in JSON format.

• Explicit mode is triggered by setting json to a known method/function string.

JSON API – Implicit

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Implicit examples• http://www.example.org/?json=1• http://www.example.org/?p=47&json=1• http://www.example.org/tag/security-issues/?json=1

Content for existing page is returned in JSON format rather than a web page.e.g.Return all posts with tag “security-issues” and list them on an external site

JSON API – Explicit

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Explicit examples• http://www.example.org/?json=get_recent_posts• http://www.example.org/?json=get_post&post_id=47• http://www.example.org/?json=get_tag_posts&tag_slug=security-issues

These all call functions rather than existing web page URLs.

All returned in JSON format.

Available When?

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Slated for WordPress 4.1 – December 2014

Where can you find out more?GitHub: https://github.com/WP-API/WP-API

Plugin: http://wordpress.org/plugins/json-api/

Image Credits

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[1] wikipedia.com

Questions Anyone?

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