title: DRF - Giving feedback to developer regarding bad inputs using django-filters
body: <p>I'm developing a REST API with django rest framework but I'm not finding a way of validating the inputs from the request with django-filters. </p>
  
  <p>For example, say I have the model:</p>
  
  <pre><code>class Event(models.Model):
      timestamp = models.DateTimeField(help_text="Time it was created")
      is_important = models.BooleanField(help_text="If the event is important")
  </code></pre>
  
  <p>And I have the filter: </p>
  
  <pre><code>class EventFilter(filters.FilterSet):
      important = filters.BooleanFilter(name='is_important')
      since = filters.IsoDateTimeFilter(name='timestamp', lookup_type='gt')
  
      class Meta:
          model = Event
  </code></pre>
  
  <p>If, in my request, I insert a bad date like <strong>{url}/?since=2016-02-31T00:00Z</strong> or <strong>{url}/?since=yesterday</strong>, instead of receiving feedback about what is wrong with the request, the API will just returns a list without any results. This doesn't indicate that the developer made a bad request, it could just mean that there are no events under those terms. </p>
  
  <p>The inverse happens with booleans, if in my request I send <strong>{url}/?is_important=maybe</strong>, it will return all the results without any filtering. </p>
  
  <p>So, my question is: Does DRF have a way of validating these kind of inputs and return a meaningful response to the developer? Thank you. </p>