Play Framework: automatic validation of controller methods applied?

Question

I have some issue with validation of parameters passed to a controller method.

Following the suggestion from the tutorial, I am using the same controller method for "save" and "create new" of an entity. See example in http://www.playframework.org/documentation/1.2.4/guide9

So, my controller method looks like:

public static void saveEntity(long l, Long itemId,  
  @Required(message="error.shouldspecifyname") String name, 
  @Required(message="error.shouldspecifycategory")  String category)

If 'itemId' is not part of the data sent via an HTTP request - it is supposed to be set to 'null'.

Unfortunately, it seems like "Play" is automatically adding a validation error on the "missing" parameter.

When looking into the validation errors' list, every time 'itemId' is 'null' - I am getting an error Incorrect value for field itemId

Is it a documented behavior? Any way to override it, or "get rid" of the error.

I am handling the errors simply using redirection, like:

if(validation.hasErrors() ) 
{

            validation.keep();
            showSomePage();         
}

So the errors are displayed "out of the context" they get generated. This is the reason the "automatic" error bothers me.

Thanks for any hint.

Alexander Ponomarenko Alexander Ponomarenko · Accepted Answer · 2012-03-04T23:31:28

Most likely it fails to validate itemId because it's declared as Long, are you sure you have "Long" there ant not just "long"? We are using validation with controllers every where and it works with @Required and passed "null" to "Long" values.

Worst case you can remove error from validation object based on "itemId" key, also if you're using controller to save model object, you might want to use:

public static void saveEntity(@Required @Valid MyEntity entity) {
if(validation.hasErrors() ) {
  validation.keep();
  showSomePage();         
}
entity.save();
}

It will automaticly hook your changes inside existing entity if you pass ID from page with:

<input type="hidden" name="myEntity.id" value="${myEntity.id}">

Play Framework: automatic validation of controller methods applied?

1 Answers