adding first error handling

moto/dynamodb/responses.py

@@ -21,6 +21,9 @@ class DynamoHandler(object):
         if match:
             return match.split(".")[1]
 
+    def error(self, type_, status=400):
+        return json.dumps({'__type': type_}), dict(status=400)
+
     def dispatch(self):
         method = self.get_method_name(self.headers)
         if method:
@@ -35,7 +38,11 @@ class DynamoHandler(object):
 
     def DescribeTable(self, uri, body, headers):
         name = json.loads(body)['TableName']
-        table = dynamodb_backend.tables[name]
+        try:
+            table = dynamodb_backend.tables[name]
+        except KeyError:
+            er = 'com.amazonaws.dynamodb.v20111205#ResourceNotFoundException'
+            return self.error(er)
         return json.dumps(table.describe)
 
 

tests/test_dynamodb/test_dynamodb.py

@@ -5,6 +5,8 @@ from freezegun import freeze_time
 from moto import mock_dynamodb
 from moto.dynamodb import dynamodb_backend
 
+from boto.exception import DynamoDBResponseError
+
 
 @mock_dynamodb
 def test_list_tables():
@@ -14,6 +16,12 @@ def test_list_tables():
     assert conn.list_tables() == ['TestTable']
 
 
+@mock_dynamodb
+def test_describe_missing_table():
+    conn = boto.connect_dynamodb('the_key', 'the_secret')
+    conn.describe_table.when.called_with('messages').should.throw(DynamoDBResponseError)
+
+
 @freeze_time("2012-01-14")
 @mock_dynamodb
 def test_describe_table():