Model and Repository¶
Usually this would now be the time to write a database schema which contains table definitions and lays out relations between the different tables. But FLOW3 doesn’t deal with tables. You won’t even access a database manually nor will you write SQL. The very best is if you completely forget about tables and databases and think only in terms of objects.
Tip
Code Examples
The following sections contain a lot of code which we’ll go through step by step. To make things a little simpler, the code has been simplified a little, e.g. by leaving out some non-essential properties and methods. If you want to follow the example closely or to peek at the final code, check the CheatSheet folder.
It contains everything explained in this tutorial, and more. To be on the safe side, do not copy the code explained here into new files, but rather copy the needed files from there to “your” sandbox project.
To see the full-scale code of the Blog as used by some of us, take a look at the Blog package in our Git repository.
Domain models are really the heart of your application and therefore it is vital that this layer stays clean and legible. In a FLOW3 application a model is just a plain old PHP object [1]. There’s no need to write a schema definition, subclass a special base model or implement a required interface. All FLOW3 requires from you as a specification for a model is a proper documented PHP class containing properties.
All your domain models need a place to live. The directory structure and filenames follow the conventions of our Coding Guidelines which basically means that the directories reflect the classes’ namespace while the filename is identical to the class name. The base directory for the domain models is Classes/Domain/Model/.
Blog Model¶
The code for your Blog model can be kickstarted like this:
myhost:tutorial johndoe$ ./flow3 kickstart:model TYPO3.Blog Blog title:string \
description:string 'posts:\Doctrine\Common\Collections\Collection'
That command will output the created file and a hint:
Created .../TYPO3.Blog/Classes/Domain/Model/Blog.php
As a new model was generated, don't forget to update the database schema with the respective doctrine:* commands.
Open the generated file and complete it to look like the following:
Classes/Domain/Model/Blog.php:
...
class Blog {
/**
* The blog's title.
*
* @var string
* @FLOW3\Validate(type="Text")
* @FLOW3\Validate(type="StringLength", options={ "minimum"=1, "maximum"=80 })
* @ORM\Column(length=80)
*/
protected $title = '';
/**
* A short description of the blog
*
* @var string
* @FLOW3\Validate(type="Text")
* @FLOW3\Validate(type="StringLength", options={ "maximum"=150 })
* @ORM\Column(length=150)
*/
protected $description = '';
/**
* The posts contained in this blog
*
* @var \Doctrine\Common\Collections\Collection<\TYPO3\Blog\Domain\Model\Post>
* @ORM\OneToMany(mappedBy="blog")
* @ORM\OrderBy({"date" = "DESC"})
*/
protected $posts;
/**
* Constructs a new Blog
*/
public function __construct() {
$this->posts = new \Doctrine\Common\Collections\ArrayCollection();
}
...
/**
* Adds a post to this blog
*
* @param \TYPO3\Blog\Domain\Model\Post $post
* @return void
*/
public function addPost(\TYPO3\Blog\Domain\Model\Post $post) {
$post->setBlog($this);
$this->posts->add($post);
}
/**
* Removes a post from this blog
*
* @param \TYPO3\Blog\Domain\Model\Post $post
* @return void
*/
public function removePost(\TYPO3\Blog\Domain\Model\Post $post) {
$this->posts->removeElement($post);
}
}
?>
Please remove the setPosts method as we don’t want that to be possible.
Tip
The @FLOW3… and @ORM… strings in the code are called Annotations. They are namespaced like PHP classes, so for the above code to work you must add a line like:
use Doctrine\ORM\Mapping as ORM;
to the files as well. Add it right after the use statement for the FLOW3 annotations that is already there.
Tip
Namespaces
Namespaces have been introduced in PHP 5.3. If you’re unfamiliar with its funny backslash syntax you might want to have a look at the PHP manual.
As you can see there’s nothing really fancy in it, the class mostly consists of getters and setters. Let’s take a closer look at the model line-by-line:
Classes/Domain/Model/Blog.php:
namespace TYPO3\Blog\Domain\Model;
This namespace declaration must be the very first code in your file.
Classes/Domain/Model/Blog.php:
/**
* A blog
*
* @FLOW3\Entity
*/
class Blog {
On the first glance this looks like a regular comment block, but it’s not. This comment contains annotations which are an important building block in FLOW3’s configuration mechanism.
The annotation marks this class as an entity. This is an important piece of information for the persistence framework because it declares that
- this model is an entity according to the concepts of Domain-Driven Design
- instances of this class can be persisted (i.e. stored in the database)
- According to DDD, an entity is an object which has an identity, that is even if two objects with the same values exist, their identity matters.
The model’s properties are implemented as regular class properties:
Classes/Domain/Model/Blog.php:
/**
* The blog's title.
*
* @var string
* @FLOW3\Validate(type="Text")
* @FLOW3\Validate(type="StringLength", options={ "minimum"=1, "maximum"=80 })
* @ORM\Column(length=80)
*/
protected $title = '';
/**
* A short description of the blog
*
* @var string
* @FLOW3\Validate(type="Text")
* @FLOW3\Validate(type="StringLength", options={ "maximum"=150 })
* @ORM\Column(length=150)
*/
protected $description = '';
/**
* The posts contained in this blog
*
* @var \Doctrine\Common\Collections\Collection<\TYPO3\Blog\Domain\Model\Post>
* @ORM\OneToMany(mappedBy="blog")
* @ORM\OrderBy({"date" = "DESC"})
*/
protected $posts;
Each property comes with a @var annotation which declares its type. Any type is fine, be it simple types like string, integer, boolean or classes like \DateTime and \TYPO3\Foo\Domain\Model\Bar.
The @var annotation of the $posts property differs a bit from the remaining comments when it comes to the type. This property holds a list of Post objects contained by this blog – in fact this could easily have been an array. However, an array does not allow the collection to be persisted by Doctrine 2 properly. We therefore use a Doctrine\Common\Collections\Collection [2] instance. The class name bracketed by the less-than and greater-than signs gives an important hint on the content of the collection (or array). There are a few situations in which FLOW3 relies on this information.
The OneToMany annotation is Doctrine 2 specific and provides more detail on the type association a property represents. In this case it tells Doctrine that a Blog may be associated with many Post instances, but those in turn may only belong to one Blog. Furthermore the mappedBy attribute says the association is bidirectional and refers to the property $blog in the Post class.
The OrderBy annotation is regular Doctrine 2 functionality and makes sure the posts are always ordered by their date property when the collection is loaded.
The remaining code shouldn’t hold any surprises - it only serves for setting and retrieving the blog’s properties. This again, is no requirement by FLOW3 - if you don’t want to expose your properties it’s fine to not define any setters or getters at all. The persistence framework uses other ways to access the properties’ values ...
We need a model for the posts as well, so kickstart it like this:
./flow3 kickstart:model --force TYPO3.Blog Post \
'blog:\TYPO3\Blog\Domain\Model\Blog' \
title:string \
linkTitle:string \
date:\DateTime \
author:string \
content:string
Note that we use the --force option to overwrite the model - it was created along with the Post controller earlier because we used the --generate-related flag.
Adjust the generated code as follows:
Classes/Domain/Model/Post.php:
/**
* The blog
* @var \TYPO3\Blog\Domain\Model\Blog
* @ORM\ManyToOne(inversedBy="posts")
*/
protected $blog;
...
/**
* The content
* @var string
* @ORM\Column(type="text")
*/
protected $content;
/**
* Constructs this post
*/
public function __construct() {
$this->date = new \DateTime();
}
...
/**
* Sets this Post's title
*
* @param string $title The Post's title
* @return void
*/
public function setTitle($title) {
$this->title = $title;
if ($this->linkTitle === '') {
$this->linkTitle = strtolower(preg_replace('/[^a-zA-Z0-9\-]/', '', str_replace(' ', '-', $title)));
}
}
...
/**
* Get the Post's link title
*
* @return string The Post's link title
*/
public function getLinkTitle() {
if ($this->linkTitle === '') {
$this->linkTitle = strtolower(preg_replace('/[^a-zA-Z0-9\-]/', '', str_replace(' ', '-', $this->title)));
}
return $this->linkTitle;
}
Blog Repository¶
According to our earlier reasonings, you need a repository for storing the blog:
Blog Repository and Blog
A repository acts as the bridge between the holy lands of business logic (domain models) and the dirty underground of infrastructure (data storage). This is the only place where queries to the persistence framework take place - you never want to have those in your domain models.
Similar to models the directory for your repositories is Classes/Domain/Repository/. You can kickstart the repository with:
myhost:tutorial johndoe$ ./flow3 kickstart:repository TYPO3.Blog Blog
This will generate a vanilla repository for blogs containing this code:
Classes/Domain/Repository/BlogRepository.php:
<?php
namespace TYPO3\Blog\Domain\Repository;
/* *
* This script belongs to the FLOW3 package "TYPO3.Blog". *
* *
* */
/**
* A repository for Blogs
*
* @FLOW3\Scope("singleton")
*/
class BlogRepository extends \TYPO3\FLOW3\Persistence\Repository {
// add customized methods here
}
?>
As you see there’s no code you need to write for the standard cases because the base repository already comes with methods like add, remove, findAll, findBy* and findOneBy* [3] methods.
Remember that a repository can only store one kind of an object, in this case blogs. The type is derived from the repository name: because you named this repository BlogRepository FLOW3 assumes that it’s supposed to store Blog objects.
To finish up, open the repository for our posts (which was generated along with the Post controller we kickstarted earlier) and add the following find methods to the generated code:
Classes/Domain/Repository/BlogRepository.php:
/**
* Finds posts by the specified blog
*
* @param \TYPO3\Blog\Domain\Model\Blog $blog The blog the post must refer to
* @param integer $limit The number of posts to return at max
* @return \TYPO3\FLOW3\Persistence\QueryResultProxy The posts
*/
public function findByBlog(\TYPO3\Blog\Domain\Model\Blog $blog) {
$query = $this->createQuery();
return $query->matching($query->equals('blog', $blog))
->setOrderings(array('date' => QueryInterface::ORDER_DESCENDING))
->execute();
}
/**
* Finds the previous of the given post
*
* @param \TYPO3\Blog\Domain\Model\Post $post The reference post
* @return \TYPO3\Blog\Domain\Model\Post
*/
public function findPrevious(\TYPO3\Blog\Domain\Model\Post $post) {
$query = $this->createQuery();
return $query->matching($query->lessThan('date', $post->getDate()))
->setOrderings(array('date' => \TYPO3\FLOW3\Persistence\QueryInterface::ORDER_DESCENDING))
->execute()
->getFirst();
}
/**
* Finds the post next to the given post
*
* @param \TYPO3\Blog\Domain\Model\Post $post The reference post
* @return \TYPO3\Blog\Domain\Model\Post
*/
public function findNext(\TYPO3\Blog\Domain\Model\Post $post) {
$query = $this->createQuery();
return $query->matching($query->greaterThan('date', $post->getDate()))
->setOrderings(array('date' => \TYPO3\FLOW3\Persistence\QueryInterface::ORDER_ASCENDING))
->execute()
->getFirst();
}
| [1] | We love to call them POPOs, similar to POJOs http://en.wikipedia.org/wiki/Plain_Old_Java_Object |
| [2] | http://www.doctrine-project.org/docs/orm/2.1/en/reference/association-mapping.html#collections |
| [3] | findBy* and findOneBy* are magic methods provided by the base repository which allow you to find objects by properties. The BlogRepository for example would allow you to call magic methods like findByDescription('foo') or findOneByTitle('bar'). |
