Adding validation to Models. Needs docs.

application/Config/Services.php

@@ -513,6 +513,25 @@ class Services
 
 	//--------------------------------------------------------------------
 
+    /**
+     * The Validation class provides tools for validating input data.
+     */
+    public static function validation(Validation $config = null, $getShared = true)
+    {
+        if ($getShared)
+        {
+            return self::getSharedInstance('validation', $config);
+        }
+
+        if (is_null($config))
+        {
+            $config = new Validation();
+        }
+
+        return new \CodeIgniter\Validation\Validation($config);
+    }
+
+    //--------------------------------------------------------------------
 
 	//--------------------------------------------------------------------
 	// Utility Methods - DO NOT EDIT

system/Model.php

@@ -37,9 +37,9 @@
  */
 
 use CodeIgniter\Pager\Pager;
+use CodeIgniter\Validation\ValidationInterface;
 use Config\App;
 use Config\Database;
-//use Config\Services;
 use CodeIgniter\Config\BaseConfig;
 use CodeIgniter\Database\BaseBuilder;
 use CodeIgniter\Database\BaseConnection;
@@ -191,6 +191,38 @@ class Model
 	 */
 	protected $builder;
 
+    /**
+     * Rules used to validate data in insert, update, and save methods.
+     * The array must match the format of data passed to the Validation
+     * library.
+     *
+     * @var array
+     */
+    protected $validationRules = [];
+
+    /**
+     * Contains any custom error messages to be
+     * used during data validation.
+     *
+     * @var array|null
+     */
+    protected $validationMessages = null;
+
+    /**
+     * Skip the model's validation. Used in conjunction with skipValidation()
+     * to skip data validation for any future calls.
+     *
+     * @var bool
+     */
+    protected $skipValidation = false;
+
+    /**
+     * Our validator instance.
+     *
+     * @var \CodeIgniter\Validation\ValidationInterface
+     */
+    protected $validation;
+
 	//--------------------------------------------------------------------
 
 	/**
@@ -199,7 +231,7 @@ class Model
 	 * @param ConnectionInterface $db
 	 * @param BaseConfig $config        Config/App()
 	 */
-	public function __construct(ConnectionInterface &$db = null, BaseConfig $config = null)
+	public function __construct(ConnectionInterface &$db = null, BaseConfig $config = null, ValidationInterface $validation = null)
 	{
 		if ($db instanceof ConnectionInterface)
 		{
@@ -220,6 +252,12 @@ class Model
 
 		$this->tempReturnType     = $this->returnType;
 		$this->tempUseSoftDeletes = $this->useSoftDeletes;
+
+        if (is_null($validation))
+        {
+            $validation = \Config\Services::validation();
+        }
+        $this->validation = $validation;
 	}
 
 	//--------------------------------------------------------------------
@@ -532,6 +570,15 @@ class Model
 	 */
 	public function insert($data)
 	{
+	    // Validate data before saving.
+	    if ($this->skipValidation === false)
+        {
+            if ($this->validate($data) === false)
+            {
+                return false;
+            }
+        }
+
 		// Must be called first so we don't
 		// strip out created_at values.
 		$data = $this->doProtectFields($data);
@@ -569,6 +616,15 @@ class Model
 	 */
 	public function update($id, $data)
 	{
+	    // Validate data before saving.
+        if ($this->skipValidation === false)
+        {
+            if ($this->validate($data) === false)
+            {
+                return false;
+            }
+        }
+
 		// Must be called first so we don't
 		// strip out updated_at values.
 		$data = $this->doProtectFields($data);
@@ -953,6 +1009,95 @@ class Model
 
 	//--------------------------------------------------------------------
 
+    /**
+     * Grabs the last error(s) that occurred. If data was validated,
+     * it will first check for errors there, otherwise will try to
+     * grab the last error from the Database connection.
+     *
+     * @param bool $forceDB   Always grab the db error, not validation
+     *
+     * @return array|null
+     */
+    public function errors(bool $forceDB = false)
+    {
+        // Do we have validation errors?
+        if ($forceDB === false && $this->skipValidation === false)
+        {
+            $errors = $this->validation->getErrors();
+
+            if (! empty($errors))
+            {
+                return $errors;
+            }
+        }
+
+        // Still here? Grab the database-specific error, if any.
+        $error = $this->db->getError();
+
+        return $error['message'] ?? null;
+    }
+
+    //--------------------------------------------------------------------
+
+    //--------------------------------------------------------------------
+    // Validation
+    //--------------------------------------------------------------------
+
+    /**
+     * Set the value of the skipValidation flag.
+     *
+     * @param bool $skip
+     *
+     * @return $this
+     */
+    public function skipValidation(bool $skip = true)
+    {
+        $this->skipValidation = $skip;
+
+        return $this;
+    }
+
+    //--------------------------------------------------------------------
+
+    /**
+     * Validate the data against the validation rules (or the validation group)
+     * specified in the class property, $validationRules.
+     *
+     * @param array $data
+     *
+     * @return bool
+     */
+    public function validate($data): bool
+    {
+        if ($this->skipValidation === true || empty($this->validationRules))
+        {
+            return true;
+        }
+
+        // Query Builder works with objects as well as arrays,
+        // but validation requires array, so cast away.
+        if (is_object($data))
+        {
+            $data = (array)$data;
+        }
+
+        // ValidationRules can be either a string, which is the group name,
+        // or an array of rules.
+        if (is_string($this->validationRules))
+        {
+            $valid = $this->validation->run($data, $this->validationRules);
+        }
+        else
+        {
+            $this->validation->setRules($this->validationRules, $this->validationMessages);
+            $valid = $this->validation->run($data);
+        }
+
+        return (bool)$valid;
+    }
+
+    //--------------------------------------------------------------------
+
 
 	//--------------------------------------------------------------------
 	// Magic

tests/_support/Models/ValidModel.php

@@ -0,0 +1,27 @@
+<?php namespace Tests\Support\Models;
+
+use CodeIgniter\Model;
+
+class ValidModel extends Model
+{
+	protected $table = 'job';
+
+	protected $returnType = 'object';
+
+	protected $useSoftDeletes = false;
+
+	protected $dateFormat = 'integer';
+
+    protected $allowedFields = ['name', 'description'];
+
+    protected $validationRules = [
+        'name' => 'required|min_length[3]'
+    ];
+
+    protected $validationMessages = [
+        'name' => [
+            'required' => 'You forgot to name the baby.',
+            'min_length' => 'Too short, man!'
+        ]
+    ];
+}

tests/system/Database/Live/ModelTest.php

@@ -3,6 +3,7 @@
 use CodeIgniter\Model;
 use Tests\Support\Models\JobModel;
 use Tests\Support\Models\UserModel;
+use Tests\Support\Models\ValidModel;
 
 /**
  * @group DatabaseLive
@@ -260,7 +261,7 @@ class ModelTest extends \CIDatabaseTestCase
 		$data = new \stdClass();
 		$data->name = 'Magician';
 		$data->description = 'Makes peoples things dissappear.';
-		
+
 		$model->protect(false)->save($data);
 
 		$this->seeInDatabase('job', ['name' => 'Magician']);
@@ -443,5 +444,35 @@ class ModelTest extends \CIDatabaseTestCase
 
 	//--------------------------------------------------------------------
 
+    public function testValidationBasics()
+    {
+        $model = new ValidModel($this->db);
+
+        $data = [
+            'description' => 'some great marketing stuff'
+        ];
+
+        $this->assertFalse($model->insert($data));
+
+        $errors = $model->errors();
+
+        $this->assertEquals('You forgot to name the baby.', $errors['name']);
+    }
+
+    //--------------------------------------------------------------------
+
+    public function testSkipValidation()
+    {
+        $model = new ValidModel($this->db);
+
+        $data = [
+            'name' => '2',
+            'description' => 'some great marketing stuff'
+        ];
+
+        $this->assertTrue(is_numeric($model->skipValidation(true)->insert($data)));
+    }
+
+    //--------------------------------------------------------------------
 
 }