IdentityInterface

API reference › yii › web › IdentityInterface

interface	`yii\web\IdentityInterface`
Since	2.0
Source	`framework/web/IdentityInterface.php`

IdentityInterface is the interface that should be implemented by a class providing identity information.

This interface can typically be implemented by a user model class. For example, the following code shows how to implement this interface by a User ActiveRecord class:

class User extends ActiveRecord implements IdentityInterface
{
    public static function findIdentity($id)
    {
        return static::findOne($id);
    }

    public static function findIdentityByAccessToken($token, $type = null)
    {
        return static::findOne(['access_token' => $token]);
    }

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

    public function getAuthKey()
    {
        return $this->authKey;
    }

    public function validateAuthKey($authKey)
    {
        return $this->authKey === $authKey;
    }
}

In some situations not all of these methods are required to be implemented. For example, if your application is a pure stateless RESTful application, you would only need to implement findIdentityByAccessToken() and getId() while leaving all other methods with an empty body. Or if your application uses session only authentication, you would need to implement all the methods except findIdentityByAccessToken().

Methods

Method	Description	Defined by
`findIdentity()` static abstract	Finds an identity by the given ID.	`IdentityInterface`
`findIdentityByAccessToken()` static abstract	Finds an identity by the given token.	`IdentityInterface`
`getAuthKey()` abstract	Returns a key that can be used to check the validity of a given identity ID.	`IdentityInterface`
`getId()` abstract	Returns an ID that can uniquely identify a user identity.	`IdentityInterface`
`validateAuthKey()` abstract	Validates the given auth key.	`IdentityInterface`

Method details

findIdentity()

abstract public static function findIdentity(string|int $id): yii\web\IdentityInterface|null

Finds an identity by the given ID.

Parameters

Parameter	Type	Description
`$id`	`string\|int`	The ID to be looked for

Returns

IdentityInterface|null: The identity object that matches the given ID. Null should be returned if such an identity cannot be found or the identity is not in an active state (disabled, deleted, etc.)

findIdentityByAccessToken()

abstract public static function findIdentityByAccessToken(mixed $token, mixed $type = null): yii\web\IdentityInterface|null

Finds an identity by the given token.

Parameters

Parameter	Type	Description
`$token`	`mixed`	The token to be looked for
`$type`	`mixed`	The type of the token. The value of this parameter depends on the implementation. For example, `HttpBearerAuth` will set this parameter to be `yii\filters\auth\HttpBearerAuth`.

Returns

IdentityInterface|null: The identity object that matches the given token. Null should be returned if such an identity cannot be found or the identity is not in an active state (disabled, deleted, etc.)

getAuthKey()

abstract public function getAuthKey(): string|null

Returns a key that can be used to check the validity of a given identity ID.

The key should be unique for each individual user, and should be persistent so that it can be used to check the validity of the user identity.

The space of such keys should be big enough to defeat potential identity attacks.

The returned key is used to validate session and auto-login (if User::$enableAutoLogin is enabled).

Make sure to invalidate earlier issued authKeys when you implement force user logout, password change and other scenarios, that require forceful access revocation for old sessions.

Returns

string|null: A key that is used to check the validity of a given identity ID.

See also

validateAuthKey()

getId()

abstract public function getId(): string|int

Returns an ID that can uniquely identify a user identity.

Returns

string|int: An ID that uniquely identifies a user identity.

validateAuthKey()

abstract public function validateAuthKey(string $authKey): bool|null

Validates the given auth key.

Parameters

Parameter	Type	Description
`$authKey`	`string`	The given auth key

Returns

bool|null: Whether the given auth key is valid.

See also

getAuthKey()