add basic awslambda get_policy

moto/awslambda/responses.py

@@ -57,6 +57,20 @@ class LambdaResponse(BaseResponse):
         else:
             raise ValueError("Cannot handle {0} request".format(request.method))
 
+    def policy(self, request, full_url, headers):
+        if request.method == 'GET':
+            return self._get_policy(request, full_url, headers)
+
+    def _get_policy(self, request, full_url, headers):
+        lambda_backend = self.get_lambda_backend(full_url)
+
+        path = request.path if hasattr(request, 'path') else request.path_url
+        function_name = path.split('/')[-2]
+        if lambda_backend.has_function(function_name):
+            return 200, {}, json.dumps(dict(Policy='test_policy'))
+        else:
+            return 404, {}, "{}"
+
     def _invoke(self, request, full_url):
         response_headers = {}
         lambda_backend = self.get_lambda_backend(full_url)

moto/awslambda/urls.py

@@ -12,5 +12,6 @@ url_paths = {
     r'{0}/(?P<api_version>[^/]+)/functions/(?P<function_name>[\w_-]+)/?$': response.function,
     r'{0}/(?P<api_version>[^/]+)/functions/(?P<function_name>[\w_-]+)/invocations/?$': response.invoke,
     r'{0}/(?P<api_version>[^/]+)/functions/(?P<function_name>[\w_-]+)/invoke-async/?$': response.invoke_async,
-    r'{0}/(?P<api_version>[^/]+)/tags/(?P<resource_arn>.+)': response.tag
+    r'{0}/(?P<api_version>[^/]+)/tags/(?P<resource_arn>.+)': response.tag,
+    r'{0}/(?P<api_version>[^/]+)/functions/(?P<function_name>[\w_-]+)/policy/?$': response.policy
 }