http://j4mie.github.com/idiormandparis/
A lightweight Active Record implementation for PHP5.
Built on top of Idiorm.
Tested on PHP 5.2.0+ - may work on earlier versions with PDO and the correct database drivers.
Released under a BSD license.
- Extremely simple configuration.
- Exposes the full power of Idiorm's fluent query API.
- Supports associations.
- Simple mechanism to encapsulate common queries in filter methods.
- Built on top of PDO.
- Uses prepared statements throughout to protect against SQL injection attacks.
- Database agnostic. Currently supports SQLite and MySQL. May support others, please give it a try!
- Setup composer for installation via packagist (j4mie/paris)
- Add in basic namespace support, see issue #20
- Allow properties to be set as an associative array in
set()
, see issue #13 - Patch in idiorm now allows empty models to be saved (j4mie/idiorm see issue #58)
- Fix incorrect tests, see issue #12
- Add
is_dirty
method
- Initial release
Paris is built with the same less is more philosophy as Idiorm.
This library is available through Packagist with the vendor and package identifier of j4mie/idiorm
Please see the Packagist documentation for further information.
You can clone the git repository, download idiorm.php or a release tag and then drop the idiorm.php file in the vendors/3rd party/libs directory of your project.
Paris requires Idiorm. Install Idiorm and Paris somewhere in your project directory, and require
both.
require_once 'your/path/to/idiorm.php';
require_once 'your/path/to/paris.php';
Then, you need to tell Idiorm how to connect to your database. For full details of how to do this, see Idiorm's documentation.
Briefly, you need to pass a Data Source Name connection string to the configure
method of the ORM class.
ORM::configure('sqlite:./example.db');
You may also need to pass a username and password to your database driver, using the username
and password
configuration options. For example, if you are using MySQL:
ORM::configure('mysql:host=localhost;dbname=my_database');
ORM::configure('username', 'database_user');
ORM::configure('password', 'top_secret');
You should create a model class for each entity in your application. For example, if you are building an application that requires users, you should create a User
class. Your model classes should extend the base Model
class:
class User extends Model {
}
Paris takes care of creating instances of your model classes, and populating them with data from the database. You can then add behaviour to this class in the form of public methods which implement your application logic. This combination of data and behaviour is the essence of the Active Record pattern.
Your User
class should have a corresponding user
table in your database to store its data.
By default, Paris assumes your class names are in CapWords style, and your table names are in lowercase_with_underscores style. It will convert between the two automatically. For example, if your class is called CarTyre
, Paris will look for a table named car_tyre
.
To override this default behaviour, add a public static property to your class called $_table
:
class User extends Model {
public static $_table = 'my_user_table';
}
Paris requires that your database tables have a unique primary key column. By default, Paris will use a column called id
. To override this default behaviour, add a public static property to your class called $_id_column
:
class User extends Model {
public static $_id_column = 'my_id_column';
}
Note - Paris has its own default ID column name mechanism, and does not respect column names specified in Idiorm's configuration.
Querying allows you to select data from your database and populate instances of your model classes. Queries start with a call to a static factory method on the base Model
class that takes a single argument: the name of the model class you wish to use for your query. This factory method is then used as the start of a method chain which gives you full access to Idiorm's fluent query API. See Idiorm's documentation for details of this API.
For example:
$users = Model::factory('User')
->where('name', 'Fred')
->where_gte('age', 20)
->find_many();
You can also use the same shortcut provided by Idiorm when looking up a record by its primary key ID:
$user = Model::factory('User')->find_one($id);
The only differences between using Idiorm and using Paris for querying are as follows:
-
You do not need to call the
for_table
method to specify the database table to use. Paris will supply this automatically based on the class name (or the$_table
static property, if present). -
The
find_one
andfind_many
methods will return instances of your model subclass, instead of the baseORM
class. Like Idiorm,find_one
will return a single instance orfalse
if no rows matched your query, whilefind_many
will return an array of instances, which may be empty if no rows matched. -
Custom filtering, see next section.
You may also retrieve a count of the number of rows returned by your query. This method behaves exactly like Idiorm's count
method:
$count = Model::factory('User')->where_lt('age', 20)->count();
Paris provides a simple API for one-to-one, one-to-many and many-to-many relationships (associations) between models. It takes a different approach to many other ORMs, which use associative arrays to add configuration metadata about relationships to model classes. These arrays can often be deeply nested and complex, and are therefore quite error-prone.
Instead, Paris treats the act of querying across a relationship as a behaviour, and supplies a family of helper methods to help generate such queries. These helper methods should be called from within methods on your model classes which are named to describe the relationship. These methods return ORM instances (rather than actual Model instances) and so, if necessary, the relationship query can be modified and added to before it is run.
The following list summarises the associations provided by Paris, and explains which helper method supports each type of association:
Use has_one
in the base, and belongs_to
in the associated model.
Use has_many
in the base, and belongs_to
in the associated model.
Use has_many_through
in both the base and associated models.
Below, each association helper method is discussed in detail.
One-to-one relationships are implemented using the has_one
method. For example, say we have a User
model. Each user has a single Profile
, and so the user
table should be associated with the profile
table. To be able to find the profile for a particular user, we should add a method called profile
to the User
class (note that the method name here is arbitrary, but should describe the relationship). This method calls the protected has_one
method provided by Paris, passing in the class name of the related object. The profile
method should return an ORM instance ready for (optional) further filtering.
class Profile extends Model {
}
class User extends Model {
public function profile() {
return $this->has_one('Profile');
}
}
The API for this method works as follows:
// Select a particular user from the database
$user = Model::factory('User')->find_one($user_id);
// Find the profile associated with the user
$profile = $user->profile()->find_one();
By default, Paris assumes that the foreign key column on the related table has the same name as the current (base) table, with _id
appended. In the example above, Paris will look for a foreign key column called user_id
on the table used by the Profile
class. To override this behaviour, add a second argument to your has_one
call, passing the name of the column to use.
One-to-many relationships are implemented using the has_many
method. For example, say we have a User
model. Each user has several Post
objects. The user
table should be associated with the post
table. To be able to find the posts for a particular user, we should add a method called posts
to the User
class (note that the method name here is arbitrary, but should describe the relationship). This method calls the protected has_many
method provided by Paris, passing in the class name of the related objects. Pass the model class name literally, not a pluralised version. The posts
method should return an ORM instance ready for (optional) further filtering.
class Post extends Model {
}
class User extends Model {
public function posts() {
return $this->has_many('Post'); // Note we use the model name literally - not a pluralised version
}
}
The API for this method works as follows:
// Select a particular user from the database
$user = Model::factory('User')->find_one($user_id);
// Find the posts associated with the user
$posts = $user->posts()->find_many();
By default, Paris assumes that the foreign key column on the related table has the same name as the current (base) table, with _id
appended. In the example above, Paris will look for a foreign key column called user_id
on the table used by the Post
class. To override this behaviour, add a second argument to your has_many
call, passing the name of the column to use.
The 'other side' of has_one
and has_many
is belongs_to
. This method call takes identical parameters as these methods, but assumes the foreign key is on the current (base) table, not the related table.
class Profile extends Model {
public function user() {
return $this->belongs_to('User');
}
}
class User extends Model {
}
The API for this method works as follows:
// Select a particular profile from the database
$profile = Model::factory('Profile')->find_one($profile_id);
// Find the user associated with the profile
$user = $profile->user()->find_one();
Again, Paris makes an assumption that the foreign key on the current (base) table has the same name as the related table with _id
appended. In the example above, Paris will look for a column named user_id
. To override this behaviour, pass a second argument to the belongs_to
method, specifying the name of the column on the current (base) table to use.
Many-to-many relationships are implemented using the has_many_through
method. This method has only one required argument: the name of the related model. Supplying further arguments allows us to override default behaviour of the method.
For example, say we have a Book
model. Each Book
may have several Author
objects, and each Author
may have written several Books
. To be able to find the authors for a particular book, we should first create an intermediary model. The name for this model should be constructed by concatenating the names of the two related classes, in alphabetical order. In this case, our classes are called Author
and Book
, so the intermediate model should be called AuthorBook
.
We should then add a method called authors
to the Book
class (note that the method name here is arbitrary, but should describe the relationship). This method calls the protected has_many_through
method provided by Paris, passing in the class name of the related objects. Pass the model class name literally, not a pluralised version. The authors
method should return an ORM instance ready for (optional) further filtering.
class Author extends Model {
public function books() {
return $this->has_many_through('Book');
}
}
class Book extends Model {
public function authors() {
return $this->has_many_through('Author');
}
}
class AuthorBook extends Model {
}
The API for this method works as follows:
// Select a particular book from the database
$book = Model::factory('Book')->find_one($book_id);
// Find the authors associated with the book
$authors = $book->authors()->find_many();
// Get the first author
$first_author = $authors[0];
// Find all the books written by this author
$first_author_books = $first_author->books()->find_many();
The has_many_through
method takes up to four arguments, which allow us to progressively override default assumptions made by the method.
First argument: associated model name - this is mandatory and should be the name of the model we wish to select across the association.
Second argument: intermediate model name - this is optional and defaults to the names of the two associated models, sorted alphabetically and concatenated.
Third argument: custom key to base table on intermediate table - this is optional, and defaults to the name of the base table with _id
appended.
Fourth argument: custom key to associated table on intermediate table - this is optional, and defaults to the name of the associated table with _id
appended.
It is often desirable to create reusable queries that can be used to extract particular subsets of data without repeating large sections of code. Paris allows this by providing a method called filter
which can be chained in queries alongside the existing Idiorm query API. The filter method takes the name of a public static method on the current Model subclass as an argument. The supplied method will be called at the point in the chain where filter
is called, and will be passed the ORM
object as the first parameter. It should return the ORM object after calling one or more query methods on it. The method chain can then be continued if necessary.
It is easiest to illustrate this with an example. Imagine an application in which users can be assigned a role, which controls their access to certain pieces of functionality. In this situation, you may often wish to retrieve a list of users with the role 'admin'. To do this, add a static method called (for example) admins
to your Model class:
class User extends Model {
public static function admins($orm) {
return $orm->where('role', 'admin');
}
}
You can then use this filter in your queries:
$admin_users = Model::factory('User')->filter('admins')->find_many();
You can also chain it with other methods as normal:
$young_admins = Model::factory('User')
->filter('admins')
->where_lt('age', 18)
->find_many();
You can also pass arguments to custom filters. Any additional arguments passed to the filter
method (after the name of the filter to apply) will be passed through to your custom filter as additional arguments (after the ORM instance).
For example, let's say you wish to generalise your role filter (see above) to allow you to retrieve users with any role. You can pass the role name to the filter as an argument:
class User extends Model {
public static function has_role($orm, $role) {
return $orm->where('role', $role);
}
}
$admin_users = Model::factory('User')->filter('has_role', 'admin')->find_many();
$guest_users = Model::factory('User')->filter('has_role', 'guest')->find_many();
These examples may seem simple (filter('has_role', 'admin')
could just as easily be achieved using where('role', 'admin')
), but remember that filters can contain arbitrarily complex code - adding raw_where
clauses or even complete raw_query
calls to perform joins, etc. Filters provide a powerful mechanism to hide complexity in your model's query API.
The model instances returned by your queries now behave exactly as if they were instances of Idiorm's raw ORM
class.
You can access data:
$user = Model::factory('User')->find_one($id);
echo $user->name;
Update data and save the instance:
$user = Model::factory('User')->find_one($id);
$user->name = 'Paris';
$user->save();
To create a new (empty) instance, use the create
method:
$user = Model::factory('User')->create();
$user->name = 'Paris';
$user->save();
To check whether a property has been changed since the object was created (or last saved), call the is_dirty
method:
$name_has_changed = $person->is_dirty('name'); // Returns true or false
Of course, because these objects are instances of your base model classes, you can also call methods that you have defined on them:
class User extends Model {
public function full_name() {
return $this->first_name . ' ' . $this->last_name;
}
}
$user = Model::factory('User')->find_one($id);
echo $user->full_name();
To delete the database row associated with an instance of your model, call its delete
method:
$user = Model::factory('User')->find_one($id);
$user->delete();
You can also get the all the data wrapped by a model subclass instance using the as_array
method. This will return an associative array mapping column names (keys) to their values.
The as_array
method takes column names as optional arguments. If one or more of these arguments is supplied, only matching column names will be returned.
class Person extends Model {
}
$person = Model::factory('Person')->create();
$person->first_name = 'Fred';
$person->surname = 'Bloggs';
$person->age = 50;
// Returns array('first_name' => 'Fred', 'surname' => 'Bloggs', 'age' => 50)
$data = $person->as_array();
// Returns array('first_name' => 'Fred', 'age' => 50)
$data = $person->as_array('first_name', 'age');
It's generally considered a good idea to centralise your data validation in a single place, and a good place to do this is inside your model classes. This is preferable to handling validation alongside form handling code, for example. Placing validation code inside models means that if you extend your application in the future to update your model via an alternative route (say a REST API rather than a form) you can re-use the same validation code.
Despite this, Paris doesn't provide any built-in support for validation. This is because validation is potentially quite complex, and often very application-specific. Paris is deliberately quite ignorant about your actual data - it simply executes queries, and gives you the responsibility of making sure the data inside your models is valid and correct. Adding a full validation framework to Paris would probably require more code than Paris itself!
However, there are several simple ways that you could add validation to your models without any help from Paris. You could override the save()
method, check the data is valid, and return false
on failure, or call parent::save()
on success. You could create your own subclass of the Model
base class and add your own generic validation methods. Or you could write your own external validation framework which you pass model instances to for checking. Choose whichever approach is most suitable for your own requirements.
The only configuration options provided by Paris itself are the $_table
and $_id_column
static properties on model classes. To configure the database connection, you should use Idiorm's configuration system via the ORM::configure
method. See Idiorm's documentation for full details.
Paris (or Idiorm) doesn't supply any extra methods to deal with transactions, but it's very easy to use PDO's built-in methods:
// Start a transaction
ORM::get_db()->beginTransaction();
// Commit a transaction
ORM::get_db()->commit();
// Roll back a transaction
ORM::get_db()->rollBack();
For more details, see the PDO documentation on Transactions.
Idiorm can log all queries it executes. To enable query logging, set the logging
option to true
(it is false
by default).
ORM::configure('logging', true);
When query logging is enabled, you can use two static methods to access the log. ORM::get_last_query()
returns the most recent query executed. ORM::get_query_log()
returns an array of all queries executed.