Field Type Tutorial

About Field Types

Field Types are the most granular bui= lding blocks for content managed by eZ Platform. The system comes with abou= t 30 native types th= at cover most common needs (Text line, Rich text, Email, Author list, Conte= nt relation, Map location, Float, etc.)
Field Types are respons= ible for:

storing data, either using the native storage engine mechanisms, or = specific means
validating input data
making the data searchable (if applicable)
displaying an instance of the type

Custom Field Types are a very powerful type of extension, since they all= ow you to hook deep into the content model.

You can find the in-depth documentation about Field Types and their best practi= ces. It describes how each component of a Field Type interacts with the= various layers of the system, and how to implement those.

About this tutorial

This tutorial aims at covering the conception and development of a custo= m eZ Platform Field Type.

We will do this by implementing a Twe= et Field Type. It will:

accept as input the URL of a tweet (https://twitter.com/<userna= me>/status/<id>)
fetch the tweet using the twitter oEmbed API (https://= dev.twitter.com/docs/embedded-tweets)
store the tweet=E2=80=99s embed contents and URL
display the tweet's embedded version when displaying the field from = a template

Getting the code

The code created throughout this tutorial is available on github: <= a href=3D"https://github.com/ezsystems/TweetFieldTypeBundle" class=3D"exter= nal-link" rel=3D"nofollow">https://github.com/ezsystems/TweetFieldTypeBundl= e.

Steps

The bundle

Field Types, like any other eZ Platform plugin, must be provide= d as Symfony 2 bundles. This chapter will cover the creation and organizati= on of this bundle
Read more about Creating the bundle and structuring the bundle.

AP= I

This part will cover the implementation of the eZ Platform API elements = required to implement a custom Field Type
Read more about Implementing the Tweet\Value class and Implementing th= e Tweet\Type class.

Converter

Storing data from any Field Type= into the Legacy Storage Engine requires that your custom data is mapped to= the data model.
Read more about Implementing the Legacy Stora= ge Engine Converter.

Templating

Displaying a Field Type's data i= s done through a Twig template.
Read more about implementing the Field Type template.

PlatformUI integration
Viewing and editing values of the FieldType in PlatformUI requires that = you extend PlatformUI, using mostly Javascript.

You should ideally read the general extensibility documentation for PlatformUI. The p= art about templating covers view templates. Edit templates are not docu= mented at the time of writing, but Netgen has published a tutori= al that covers the topic: http://www.netgenlabs.com/Blog/Adding-s= upport-for-a-new-field-type-to-eZ-Publish-Platform-UI.