使用CakePHP的Auth组件登录时出错

Question

I've integrated Cake's Auth component into my app. It mostly seems to work ok but I quite often get an error when logging in looking something like this:

Error: Call to undefined method Security::getDataSource()
File: C:\xampp\htdocs\ips-mvc\lib\Cake\Model\Datasource\DboSource.php
Line: 1063

Any idea what this means?

For the record, I do have a model in my app called Security. I wasn't aware of any reserved model names in Cake but is there a chance my Security mdoel is conflicting with a Cake component? This error can still occur when the Security model is not used although it is quite sporadic in its appearance - sometimes refreshing the page will make everything work fine.

Any ideas?

Answer 1

The error is caused by passing a component instance to a method expecting a model instance, and are easily avoidable by not creating model classes with the same name as a component in use.

Models and Components cannot have the same name

The problem is not related to duplicate class names as Models do not have a class name suffix, yet components do.

However, for example, in a controller the following syntax:

$this->{$alias}

Is used to access both a component (class name {$alias}Component) or a model (class name $alias).

As such, having a model with the same name as a component makes one or the other inaccessible.

Cache Poisoning

However the problem doesn't stop there. Objects are stored in the class registry using an alias as the key:

For example, in Model:

 ClassRegistry::addObject($this->alias, $this);

If the same alias is used (Security model, SecurityComponent) - the object occupying the key "Security" is simply the first one to get added to the registry - all subsequent requests for "Security" will return that object.

Depending on cache expiration and whether the model and component are used in the same request - determines how often errors such as the one in the question appear and whether they are "random" or reproducible.