• 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
DataMapper 1.6.0

#1
[eluser]stensi[/eluser]
<b>UPDATE</b>

10 December 2008 - Version 1.6.0 Released (Current version)
6 December 2008 - Version 1.5.4 Released
5 December 2008 - Version 1.5.3 Released
4 December 2008 - Version 1.5.2 Released
4 December 2008 - Version 1.5.1 Released
3 December 2008 - Version 1.5.0 Released
15 October 2008 - Version 1.4.5 Released
13 October 2008 - Version 1.4.4 Released
13 October 2008 - Version 1.4.3 Released
12 October 2008 - Version 1.4.2 Released
11 October 2008 - Version 1.4.1 Released
11 October 2008 - Version 1.4 Released
8 October 2008 - Version 1.3.4 Released
3 October 2008 - Version 1.3.3 Released
2 October 2008 - Version 1.3.2 Released
2 October 2008 - Version 1.3.1 Released
29 September 2008 - Version 1.3.0 Released
24 September 2008 - Version 1.2.1 Released
17 September 2008 - Version 1.2 Released
7 September 2008 - Version 1.0 Released

View the Change Log to see what's changed.

____________________________________

My DataMapper is finished!

Ever since Michael Wales posted a sneak peak of the DataMapper ORM class he was working on, I was inspired to start making my own!

The concept of having your Database tables as objects, and being able to manipulate them and their relationships so easily was too appealing for me to wait. So, sorry if I'm stealing some of your thunder Michael :red:


<b>DataMapper</b>

DataMapper is an Object Relational Mapper written in PHP for CodeIgniter. It is designed to map your Database tables into easy to work with objects, fully aware of the relationships between each other.

<b>Features</b>
* Everything is an object!
* Easy to setup, easy to use.
* Custom Validation on object properties.
* Lazy Loading (related objects are only loaded upon access).
* Relations and their integrity are automatically managed for you.
* One to One, One to Many, and Many to Many relations fully supported.

I went to a lot of trouble designing this and have even gone so far as to fully document it with a dedicated User Guide!

DataMapper Source Files
DataMapper User Guide

Enjoy :-)

#2
[eluser]wiredesignz[/eluser]
Wow man, you've done an awesome job there, documentation and all.

Excellent work. Wink

#3
[eluser]Jamie Rumbelow[/eluser]
Well done!

Great library, and well documented. Keep up the good work Wink

#4
[eluser]stensi[/eluser]
Thanks guys :-)

In case people were wanting to see some examples in the thread instead, here's a simple one.

First, we'll setup a few DataMapper models:

<b>User model</b>
Code:
&lt;?php

class User extends DataMapper {

    var $has_many = array('book' => 'books');
    var $has_one = array('country' => 'countries');

    var $validation = array(
        array(
            'field' => 'username',
            'label' => 'Username',
            'rules' => array('required', 'trim', 'unique', 'alpha_dash', 'min_length' => 3, 'max_length' => 20),
        ),
        array(
            'field' => 'password',
            'label' => 'Password',
            'rules' => array('required', 'trim', 'unique', 'min_length' => 6, 'encrypt'),
        ),
        array(
            'field' => 'confirm_password',
            'label' => 'Confirm Password',
            'rules' => array('encrypt', 'matches' => 'password'),
        ),
        array(
            'field' => 'email',
            'label' => 'Email Address',
            'rules' => array('required', 'trim', 'valid_email')
        )
    );

    function User()
    {
        parent::DataMapper();
    }

    function login()
    {
        // Create a temporary user object
        $u = new User();

        // Get this users stored record via their username
        $u->where('username', $this->username)->get();

        // Give this user their stored salt
        $this->salt = $u->salt;

        // Validate and get this user by their property values,
        // this will see the 'encrypt' validation run, encrypting the password with the salt
        $this->validate()->get();

        // If the username and encrypted password matched a record in the database,
        // this user object would be fully populated, complete with their ID.

        // If there was no matching record, this user would be completely cleared so their id would be empty.
        if (empty($this->id))
        {
            // Login failed, so set a custom error message
            $this->error_message('login', 'Username or password invalid');

            return FALSE;
        }
        else
        {
            // Login succeeded
            return TRUE;
        }
    }

    // Validation prepping function to encrypt passwords
    // If you look at the $validation array, you will see the password field will use this function
    function _encrypt($field)
    {
        // Don't encrypt an empty string
        if (!empty($this->{$field}))
        {
            // Generate a random salt if empty
            if (empty($this->salt))
            {
                $this->salt = md5(uniqid(rand(), true));
            }

            $this->{$field} = sha1($this->salt . $this->{$field});
        }
    }
}

/* End of file user.php */
/* Location: ./application/models/user.php */


<b>Country model</b>
Code:
&lt;?php

class Country extends DataMapper {

    var $table = "countries";

    var $has_many = array("user" => "users");

    var $validation = array(
        array(
            'field' => 'name',
            'label' => 'Country',
            'rules' => array('required', 'trim', 'unique', 'alpha_dash', 'min_length' => 1, 'max_length' => 50),
        )

    function Country()
    {
        parent::DataMapper();
    }
}

/* End of file country.php */
/* Location: ./application/models/country.php */


<b>Book model</b>
Code:
&lt;?php

class Book extends DataMapper {

    var $has_many = array("user" => "users");

    var $validation = array(
        array(
            'field' => 'title',
            'label' => 'Title',
            'rules' => array('required', 'trim', 'unique', 'alpha_dash', 'min_length' => 1, 'max_length' => 50),
        ),
        array(
            'field' => 'description',
            'label' => 'Description',
            'rules' => array('required', 'trim', 'alpha_slash_dot', 'min_length' => 10, 'max_length' => 200),
        ),
        array(
            'field' => 'year',
            'label' => 'Year',
            'rules' => array('required', 'trim', 'numeric', 'exact_length' => 4),
        )
    );

    function Book()
    {
        parent::DataMapper();
    }
}

/* End of file book.php */
/* Location: ./application/models/book.php */

<b>UPDATE</b>

Updated to reflect version 1.3.

#5
[eluser]stensi[/eluser]
And now the good part where you get to use your tables as objects.

<b>Example controller</b>
Code:
&lt;?php

class Users extends Controller {

    function Users()
    {
        parent::Controller();
    }

    function index()
    {
        // Let's create a user
        $u = new User();
        $u->username = 'Fred Smith';
        $u->password = 'apples';
        $u->email = [email protected]';

        // And save them to the database (validation rules will run)
        if ($u->save())
        {
            // User object now has an ID
            echo 'ID: ' . $u->id . '<br />';
            echo 'Username: ' . $u->username . '<br />';
            echo 'Email: ' . $u->email . '<br />';

            // Not that we'd normally show the password, but when we do, you'll see it has been automatically encrypted
            // since the User model is setup with an encrypt rule in the $validation array for the password field
            echo 'Password: ' . $u->password . '<br />';
        }
        else
        {
            // If validation fails, we can show the error for each property
            echo $u->error->username;
            echo $u->error->password;
            echo $u->error->email;

            // or we can loop through the error's all list
            foreach ($u->error->all as $error)
            {
                echo $error;
            }

            // or we can just show all errors in one string!
            echo $u->error->string;

            // Each individual error is automatically wrapped with an error_prefix and error_suffix, which you can change (default: <p>error message</p>)
        }

        // Let's now get the first 5 books from our database
        $b = new Book();
        $b->limit(5)->get();

        // Let's look at the first book
        echo 'ID: ' . $b->id . '<br />';
        echo 'Name: ' . $b->title . '<br />';
        echo 'Description: ' . $b->description . '<br />';
        echo 'Year: ' . $b->year . '<br />';

        // Now let's look through all of them
        foreach ($b->all as $book)
        {
            echo 'ID: ' . $book->id . '<br />';
            echo 'Name: ' . $book->title . '<br />';
            echo 'Description: ' . $book->description . '<br />';
            echo 'Year: ' . $book->year . '<br />';
            echo '<br />';
        }

        // Let's relate the user to these books
        $u->save($b->all);

        // Yes, it's as simple as that! You can add relations in several ways, even different types of relations at the same time

        // Get the Country with an ID of 10
        $c = new Country();
        $c->where('id', 10)->get();

        // Get all Books from the year 2000
        $b = new Book();
        $b->where('year', 2000)->get();

        // Relate the user to them
        $u->save(array($c, $b->all));

        // Now let's access those relations from the user

        // First we'll get all related books
        $u->book->get();

        // You can just show the first related book
        echo 'ID: ' . $u->book->id . '<br />';
        echo 'Name: ' . $u->book->title . '<br />';
        echo 'Description: ' . $u->book->description . '<br />';
        echo 'Year: ' . $u->book->year . '<br />';

        // Or if you're expecting more than one, which we are, loop through all the books!
        foreach ($u->book->all as $book)
        {
            echo 'ID: ' . $book->id . '<br />';
            echo 'Name: ' . $book->title . '<br />';
            echo 'Description: ' . $book->description . '<br />';
            echo 'Year: ' . $book->year . '<br />';
            echo '<br />';

            // And there's no need to stop there,
            // we can see what other users are related to each book! (and you can chain the get() call if you don't want to do it on its own, before the loop)
            foreach ($book->user->get()->all as $user)
            {
                // Show user if it's not the original user as we want to show him the other users
                if ($user->id != $u->id)
                {
                    echo 'User ' . $user->username . ' also likes this book<br >';
                }
            }
        }

        // We know there was only one country so we'll access the first record rather than loop through $u->country->all

        // Get related country
        $u->country->get();

        echo 'User is from Country: ' . $u->country->name . '<br />';

        // One of the great things about related records is that they're only loaded when you access them!

        // Lets say the user no longer likes the first book from his year 2000 list, removing that relation is as easy as adding one!

        // This will remove the users relation to the first record in the $b object (supplying $b->all would remove relations to all books in the books current all list)
        $u->delete($b);

        // You can delete multiple relations of different types in the same way you can save them

        // Now that we're done with the user, let's delete him
        $u->delete();

        // When you delete the user, you delete all his relations with other objects. DataMapper does all the tidying up for you :)
    }

    // Continued below...

<b>UPDATE</b>

Updated to reflect version 1.3.

#6
[eluser]stensi[/eluser]
Code:
// Continued from above...

     function register()
    {
        // Create user object
        $u = new User();

        // Put user supplied data into user object
        // (no need to validate the post variables in the controller,
        // if you've set your DataMapper models up with validation rules)
        $u->username = $this->input->post('username');
        $u->password = $this->input->post('password');
        $u->confirm_password = $this->input->post('confirm_password');
        $u->email = $this->input->post('email');

        // Attempt to save the user into the database
        if ($u->save())
        {
            echo '<p>You have successfully registered</p>';
        }
        else
        {
            // Show all error messages
            echo '<p>' . $u->error->string . '</p>';
        }
    }

    function login()
    {
        // Create user object
        $u = new User();

        // Put user supplied data into user object
        // (no need to validate the post variables in the controller,
        // if you've set your DataMapper models up with validation rules)
        $u->username = $this->input->post('username');
        $u->password = $this->input->post('password');

        // Attempt to log user in with the data they supplied, using the login function setup in the User model
        // You might want to have a quick look at that login function up the top of this page to see how it authenticates the user
        if ($u->login())
        {
            echo '<p>Welcome ' . $u->username . '!</p>';
            echo '<p>You have successfully logged in so now we know that your email is ' . $u->email . '.</p>';
        }
        else
        {
            // Show the custom login error message
            echo '<p>' . $u->error->login . '</p>';
        }
    }
}

/* End of file login.php */
/* Location: ./application/controllers/login.php */

In case people are wondering when the DataMapper models are actually loaded, I'll explain.

To set it up is simply a matter of adding the main DataMapper model file to your model autoload array:
Code:
$autoload['model'] = array('datamapper');

That's it. All your models that extend DataMapper are automatically loaded by it when you create or access them, which is why there's no need to fill up your Controller's constructor with bunches of <b>$this->load->model('Object');</b> lines. DataMapper is smart enough to load them for you, as you ask for them.

<b>UPDATE</b>

Updated to reflect version 1.3.

#7
[eluser]Colin Williams[/eluser]
Wonderful stuff.

#8
[eluser]andyr[/eluser]
Great work stensi,

I am going to have a play with this now

The only thing that worries me is domain object knowing about the data mapper, in this case through inheritance. The domain object should not strictly know the data mapper and act as a layer that separates the in-memory objects from the database, which allows the transfer data between the two, while isolating them from each other.

For example,

http://www.martinfowler.com/eaaCatalog/dataMapper.html

I cant help but feel that the code examples above still feel like active record, as the data access logic is in the domain object and the object is open to carry both data and behaviour.

http://www.martinfowler.com/eaaCatalog/a...ecord.html

This is probably the just side effect of using inheritance between the domain object and data mapper, and not composition in order to keep things simple.

But anyhows, a mix between active record and data mapper is interesting.

#9
[eluser]stensi[/eluser]
Thanks andyr. I hear what you're saying about the separation and yes, the Domain Object knowing about the DataMapper is simply a side effect of the inheritance. That's where the straying from the pattern ends.

Strictly speaking I should have separated things to have a DomainObject class and the DataMapper class but for simplicity's sake, and ease of use and implementation, I felt doing it the way I did resulted in the same functionality the DataMapper pattern provides, but with much less code than would otherwise have been required.

So yes, it still sticks to the DataMapper pattern, just a little loosely in that regard.

Hope you find it useful Smile

#10
[eluser]steelaz[/eluser]
From your user guide I understand find() basically accepts "where" parameter, what we would use as $this->db->where(). Is there a way to pass "limit" or "sort" parameters?


Digg   Delicious   Reddit   Facebook   Twitter   StumbleUpon  


Users browsing this thread:
1 Guest(s)


  Theme © 2014 iAndrew  
Powered By MyBB, © 2002-2017 MyBB Group.