Better error messaging for dynamodb table gets for range key tables without range keys used. cc #28

moto/dynamodb/models.py

@@ -101,6 +101,10 @@ class Table(object):
         self.created_at = datetime.datetime.now()
         self.items = defaultdict(dict)
 
+    @property
+    def has_range_key(self):
+        return self.range_key_attr is not None
+
     @property
     def describe(self):
         results = {
@@ -122,7 +126,7 @@ class Table(object):
                 "TableSizeBytes": 0,
             }
         }
-        if self.range_key_attr:
+        if self.has_range_key:
             results["Table"]["KeySchema"]["RangeKeyElement"] = {
                 "AttributeName": self.range_key_attr,
                 "AttributeType": self.range_key_type
@@ -132,7 +136,7 @@ class Table(object):
     def __len__(self):
         count = 0
         for key, value in self.items.iteritems():
-            if self.range_key_attr:
+            if self.has_range_key:
                 count += len(value)
             else:
                 count += 1
@@ -143,7 +147,7 @@ class Table(object):
 
     def put_item(self, item_attrs):
         hash_value = DynamoType(item_attrs.get(self.hash_key_attr))
-        if self.range_key_attr:
+        if self.has_range_key:
             range_value = DynamoType(item_attrs.get(self.range_key_attr))
         else:
             range_value = None
@@ -157,6 +161,8 @@ class Table(object):
         return item
 
     def get_item(self, hash_key, range_key):
+        if self.has_range_key and not range_key:
+            raise ValueError("Table has a range key, but no range key was passed into get_item")
         try:
             if range_key:
                 return self.items[hash_key][range_key]

moto/dynamodb/responses.py

@@ -188,12 +188,17 @@ class DynamoHandler(BaseResponse):
         hash_key = key['HashKeyElement']
         range_key = key.get('RangeKeyElement')
         attrs_to_get = self.body.get('AttributesToGet')
-        item = dynamodb_backend.get_item(name, hash_key, range_key)
+        try:
+            item = dynamodb_backend.get_item(name, hash_key, range_key)
+        except ValueError:
+            er = 'com.amazon.coral.validate#ValidationException'
+            return self.error(er, status=400)
         if item:
             item_dict = item.describe_attrs(attrs_to_get)
             item_dict['ConsumedCapacityUnits'] = 0.5
             return dynamo_json_dump(item_dict)
         else:
+            # Item not found
             er = 'com.amazonaws.dynamodb.v20111205#ResourceNotFoundException'
             return self.error(er, status=404)