Move ValidationError messages to a dictionary that can be accessed from PinForm.clean

pinry/pins/forms.py

@@ -7,6 +7,13 @@ class PinForm(forms.ModelForm):
     url = forms.CharField(required=False)
     image = forms.ImageField(label='or Upload', required=False)
 
+    _errors = {
+        'not_image': 'Requested URL is not an image file. Only images are currently supported.',
+        'pinned': 'URL has already been pinned!',
+        'protocol': 'Currently only support HTTP and HTTPS protocols, please be sure you include this in the URL.',
+        'nothing': 'Need either a URL or Upload',
+    }
+
     class Meta:
         model = Pin
         fields = ['url', 'image', 'description', 'tags']
@@ -20,26 +27,18 @@ class PinForm(forms.ModelForm):
         if url:
             image_file_types = ['png', 'gif', 'jpeg', 'jpg']
             if not url.split('.')[-1].lower() in image_file_types:
-                raise forms.ValidationError("Requested URL is not an image file. "
-                                            "Only images are currently supported.")
-            try:
-                Pin.objects.get(url=url)
-                raise forms.ValidationError("URL has already been pinned!")
-            except Pin.DoesNotExist:
-                pass
+                raise forms.ValidationError(self._errors['not_image'])
             protocol = url.split(':')[0]
             if protocol not in ['http', 'https']:
-                raise forms.ValidationError("Currently only support HTTP and "
-                                            "HTTPS protocols, please be sure "
-                                            "you include this in the URL.")
+                raise forms.ValidationError(self._errors['protocol'])
             try:
                 Pin.objects.get(url=url)
-                raise forms.ValidationError("URL has already been pinned!")
+                raise forms.ValidationError(self._errors['pinned'])
             except Pin.DoesNotExist:
                 pass
         elif image:
             pass
         else:
-            raise forms.ValidationError("Need either a URL or Upload.")
+            raise forms.ValidationError(self._errors['nothing'])
 
         return cleaned_data