Refactor update creation api

This merge request does the following:

• Raise DRF errors rather than returning response to take advantage of the DRF exception handling mechanism
• Create serialisers for PUT request to simplify the code
• Improve validation checks in several places
• Fixes several issues in DRF infrastructure uses
• Fixes JSON fields handling
• Remove routes that do no fully qualify objects
• Implement a custom DRF exception handler that will allow to log errors
• Improve testing
• Improve permission management

beat/web/databases/serializers.py

@@ -25,6 +25,8 @@
 #                                                                             #
 ###############################################################################
 
+from django.conf import settings
+
 from rest_framework import serializers
 
 from ..common.serializers import VersionableSerializer
@@ -104,6 +106,12 @@ class DatabaseCreationSerializer(serializers.ModelSerializer):
         ]
         beat_core_class = beat.core.database.Database
 
+    def validate_declaration(self, declaration):
+        obj = self.Meta.beat_core_class(prefix=settings.PREFIX, data=declaration)
+        if not obj.valid:
+            raise serializers.ValidationError(obj.errors)
+        return declaration
+
     def validate(self, data):
         user = self.context.get("user")
         name = self.Meta.model.sanitize_name(data["name"])