germix/fields-formatter

Format fields of objects

dev-master 2020-12-21 11:58 UTC

GPL-3.0-or-later

README

Installation

composer require germix/fields-formatter

How to use

Suppose we have two classes called Post and Comment that implement FieldsFormatterEntity

The Post class:

class Post implements FieldsFormatterEntity
{
    private $id;
    private $user;
    private $title;
    private $status;
    private $content;
    private $comments;

    public function __construct()
    {
        $this->id = 1;
        $this->user = "John";
        $this->title = 'My post';
        $this->status = 'publish';
        $this->content = 'My post content';
        $this->comments = [
            new Comment(1, 'Peter', 'Comment 1'),
            new Comment(2, 'Louis', 'Comment 2'),
            new Comment(3, 'Richard', 'Comment 3'),
        ];
    }

    public function getId()
    {
        return $this->id;
    }

    public function getUser()
    {
        return $this->user;
    }

    public function getTitle()
    {
        return $this->title;
    }

    public function getStatus()
    {
        return $this->status;
    }

    public function getContent()
    {
        return $this->content;
    }

    public function getComments()
    {
        return $this->comments;
    }

    public function formatField($formatter, $field, $subfields, &$valid, $data)
    {
        switch($field)
        {
            case 'id':              return $this->getId();
            case 'user':            return $this->getUser();
            case 'title':           return $this->getTitle();
            case 'status':          return $this->getStatus();
            case 'content':         return $this->getContent();
            case 'comments':        return $formatter->format($this->getComments(), $subfields);
        }
        $valid = false; return null;
    }

    public function defaultFormatterFields()
    {
        return
            [ 'id'
            , 'user'
            , 'title'
            , 'status'
            , 'content'
            , 'comments'
        ];
    }
}

The Comment class:

class Comment implements FieldsFormatterEntity
{
    private $id;
    private $user;
    private $message;

    public function __construct($id, $user, $message)
    {
        $this->id = $id;
        $this->user = $user;
        $this->message = $message;
    }

    public function getId()
    {
        return $this->id;
    }

    public function getUser()
    {
        return $this->user;
    }

    public function getMessage()
    {
        return $this->message;
    }

    public function formatField($formatter, $field, $subfields, &$valid, $data)
    {
        switch($field)
        {
            case 'id':              return $this->getId();
            case 'user':            return $this->getUser();
            case 'message':         return $this->getMessage();
        }
        $valid = false; return null;
    }

    public function defaultFormatterFields()
    {
        return
            [ 'id'
            , 'user'
            , 'message'
        ];
    }
}

Suppose we have a Post object called $post, so we can format its like this

$post = new Post();
$formatter = new FieldsFormatted();
$result = $formatter->formatter($post, null);
var_dump($result);

In this case, the $post will be formatted with the defaults fields, and we will get the following result

array(6) {
    ["id"]=>
    int(1)
    ["user"]=>
    string(4) "John"
    ["title"]=>
    string(7) "My post"
    ["status"]=>
    string(7) "publish"
    ["content"]=>
    string(15) "My post content"
    ["comments"]=>
    array(3) {
        [0]=>
        array(3) {
            ["id"]=>
            int(1)
            ["user"]=>
            string(5) "Peter"
            ["message"]=>
            string(9) "Comment 1"
        }
        [1]=>
        array(3) {
            ["id"]=>
            int(2)
            ["user"]=>
            string(5) "Louis"
            ["message"]=>
            string(9) "Comment 2"
        }
        [2]=>
        array(3) {
            ["id"]=>
            int(3)
            ["user"]=>
            string(7) "Richard"
            ["message"]=>
            string(9) "Comment 3"
        }
    }
}

If we want to format some specific fields, we can use a string with comma separated fields

$result = $formatter->formatter($post, 'id,title,comments{message}');

Or using an array of fields ...

$result = $formatter->formatter($post, ['id', 'title', [ 'comments', [ 'message'] ]]);

In the same last two cases, we will obtain the following result

array(3) {
    ["id"]=>
    int(1)
    ["title"]=>
    string(7) "My post"
    ["comments"]=>
    array(3) {
        [0]=>
        array(1) {
            ["message"]=>
            string(9) "Comment 1"
        }
        [1]=>
        array(1) {
            ["message"]=>
            string(9) "Comment 2"
        }
        [2]=>
        array(1) {
            ["message"]=>
            string(9) "Comment 3"
        }
    }
}

Finally, we can encode the result as json.

echo json_encode($result, JSON_PRETTY_PRINT);

And we will get something like the following

{
    "id": 1,
    "user": "John",
    "title": "My post",
    "status": "publish",
    "content": "My post content",
    "comments": [
        {
            "id": 1,
            "user": "Peter",
            "message": "Comment 1"
        },
        {
            "id": 2,
            "user": "Louis",
            "message": "Comment 2"
        },
        {
            "id": 3,
            "user": "Richard",
            "message": "Comment 3"
        }
    ]
}