AWS X-Ray client mock. (#1255)

* X-Ray Client SDK patched

Fixes #1250

* Fixed flake8

* Fixed some issues

* Fixed flake8

* Fixed more typos

* Fixed python2 string

* Fixed aws-sdk patch order

* Added more test cases to test the patching

moto/dynamodb2/responses.py

@@ -4,7 +4,7 @@ import six
 import re
 
 from moto.core.responses import BaseResponse
-from moto.core.utils import camelcase_to_underscores
+from moto.core.utils import camelcase_to_underscores, amzn_request_id
 from .models import dynamodb_backend2, dynamo_json_dump
 
 
@@ -24,6 +24,7 @@ class DynamoHandler(BaseResponse):
     def error(self, type_, message, status=400):
         return status, self.response_headers, dynamo_json_dump({'__type': type_, 'message': message})
 
+    @amzn_request_id
     def call_action(self):
         self.body = json.loads(self.body or '{}')
         endpoint = self.get_endpoint_name(self.headers)
@@ -56,6 +57,7 @@ class DynamoHandler(BaseResponse):
         response = {"TableNames": tables}
         if limit and len(all_tables) > start + limit:
             response["LastEvaluatedTableName"] = tables[-1]
+
         return dynamo_json_dump(response)
 
     def create_table(self):