Validating Input Data with the CodeIgniter PHP Framework - Review: the complete source code of the generic model class

Before I proceed to implement a method within the generic model class that performs customized validation on the data used for inserting and updating database records, I’m going to list the model’s entire source code. This way, you’ll be able to recall more quickly how it was defined in the previous article of the series.

Having clarified that point, here’s the complete signature of the “AbstractModel” class, which now has the ability to perform CRUD operations against a specified database table. Have a look at it:

abstract class MY_Model extends Model

{

protected $table = ''; // table associated to the model

protected $fields = array(); // fields of table associated to the model

protected $id = NULL; // value of the primary key of the table associated to the model

protected $data = array(); // model input data

protected $insertID = NULL; // insertion ID

protected $numRows = NULL; // number of rows returned by SELECTS

protected $validation = array(); // model validation rules

protected $errors = array(); // model errors

/**

* Constructor

*

* @access protected

*/

protected function __construct()

{

parent::Model();

// get CI super object as a model property

$this->ci =& get_instance();

}

/**

* Sets associated table data for the model

*

* @author Alejandro Gervasio

* @return void

* @access public

*/

public function setTableData($table = 'default')

{

if ($this->db->table_exists($table))

{

$this->table = $table;

$this->fields = $this->db->field_names($this->table);

}

}

/**

* Sets value of primary key of the associated table for the model

*

* @author Alejandro Gervasio

* @param integer

* @return void

* @access public

*/

public function setID($id)

{

$this->id = is_integer($id) AND $id > 0 ? $id : 1;

}

/**

* Gets value of primary key of the associated table for the model

*

* @author Alejandro Gervasio

* @return integer

* @access public

*/

public function getID()

{

return $this->id;

}

/** Sets input data for the model

*

* @author Alejandro Gervasio

* @param array

* @return void

* @access public

*/

public function setData($data)

{

if ( is_array($data) AND count($data) > 0)

{

foreach ($data as $key => $value)

{

if (array_search($key, $this->fields) === FALSE)

{

unset($data[$key]);

}

}

$this->data = $data;

}

}

/**

* Sets validation rules for model data

*

* @author Alejandro Gervasio

* @param array

* @return void

* @access public

*/

public function setValidation($validation)

{

if ( is_array($validation) AND count($validation) > 0)

{

foreach ($validation as $field => $rule)

{

if (array_search($field, $this->fields) === FALSE)

{

unset($validation[$key]);

}

}

$this->validation = $validation;

}

}

/**

* Returns a result set with specified fields according to given conditions.

*

* @author Alejandro Gervasio

* @return query result on success - Boolean FALSE on failure

* @access public

*/

public function fetch($fields = '*', $where = NULL, $order = 'id ASC', $limit = NULL, $offset = 0, $join = NULL)

{

if ($fields != '*')

{

$this->db->select($fields);

}

if ($this->id != NULL)

{

$this->db->where('id', $this->id);

}

elseif($where != NULL)

{

$this->db->where($where);

}

if ($order != 'id ASC')

{

$this->db->orderby($order);

}

if ($limit != NULL)

{

$this->db->limit($limit, $offset);

}

if( $join != NULL)

{

$this->db->join($join);

}

$query = $this->db->get($this->table);

$this->numRows = $query->num_rows();

if ($this->numRows > 0)

{

return ($this->numRows > 1 ) ? $query->result() : $query->row();

}

$this->errors[] ='No rows were returned by the query.';

return FALSE;

}

/** Saves model data into associated table (validation rules are applied to input data)

*

*

* @author Alejandro Gervasio

* @return integer on success - Boolean FALSE on failure

* @access public

*/

public function save()

{

if ($this->data == NULL)

{

$this->errors[] = 'Error saving row.';

return FALSE;

}

// validate input data

if( !$this->validate())

{

return FALSE;

}

// Insert new row if ID was not set in the model

if ($this->id == NULL)

{

$this->db->insert($this->table, $this->data);

$this->insertID = $this->db->insert_id();

return $this->insertID;

}

// Otherwise update existing row

else

{

$this->db->where('id', $this->id)->update($this->table, $this->data);

return $this->db->affectedRows;

}

}

/** Deletes model data from associated table (validation rules are applied to input data)

*

*

* @author Alejandro Gervasio

* @return Boolean TRUE on success - Boolean FALSE on failure

* @access public

*/

public function delete()

{

if ($this->id == NULL)

{

$this->errors[] = 'Error deleting row.';

return FALSE;

}

$this->db->where('id', $this->id)->delete($this->table);

return TRUE;

}

}

As you’ll possibly recall after analyzing the source code above, at this point the model is capable of retrieving, inserting, updating and deleting database records by means of the respective “fetch(),” “save()” and “delete()” methods, which admittedly are pretty intuitive. Nonetheless, as you may have noticed, the “save()” method checks the validity of its incoming data via another protected function, not surprisingly called “validate().”

You're probably wondering how this method looks. Well, it’s hasn’t been defined yet, but don’t worry; in the following section, I’m going to show you its implementation, thus dissipating any doubts that you may have regarding its functionality.

Thus, to learn how the private “validate()” method will be coded, click on the link that appears below and read the following segment.

Next: Adding validation capabilities to the generic model class >>
 

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