add validation for StartingPosition when Stream is specified

samtranslator/model/eventsources/pull.py

@@ -52,6 +52,10 @@ def to_cloudformation(self, **kwargs):
         if not self.Stream and not self.Queue:
             raise InvalidEventException(
                 self.relative_id, "No Queue (for SQS) or Stream (for Kinesis or DynamoDB) provided.")
+
+        if self.Stream and not self.StartingPosition:
+            raise InvalidEventException(
+                self.relative_id, "StartingPosition is required for Kinesis and DynamoDB.")
 
         lambda_eventsourcemapping.FunctionName = function_name_or_arn
         lambda_eventsourcemapping.EventSourceArn = self.Stream or self.Queue

tests/translator/input/error_missing_startingposition.yaml

@@ -0,0 +1,13 @@
+Resources:
+  KinesisFunction:
+      Type: 'AWS::Serverless::Function'
+      Properties:
+        CodeUri: s3://sam-demo-bucket/streams.zip
+        Handler: stream.kinesis_handler
+        Runtime: python2.7
+        Events:
+          MyKinesisStream:
+            Type: Kinesis
+            Properties:
+              Stream: arn:aws:kinesis:us-west-2:012345678901:stream/my-stream
+              BatchSize: 100

tests/translator/output/error_missing_startingposition.json

@@ -0,0 +1,6 @@
+{
+  "errors": [{
+    "errorMessage": "Resource with id [KinesisFunction] is invalid. Event with id [MyKinesisStream] is invalid. StartingPosition is required for Kinesis and DynamoDB."
+  }],
+  "errorMessage": "Invalid Serverless Application Specification document. Number of errors found: 1. Resource with id [KinesisFunction] is invalid. Event with id [MyKinesisStream] is invalid. StartingPosition is required for Kinesis and DynamoDB."
+}

tests/translator/test_translator.py

@@ -158,6 +158,7 @@ def test_transform_success(self, testcase, partition_with_region):
     'error_function_with_invalid_deployment_preference_hook_property',
     'error_invalid_logical_id',
     'error_missing_queue',
+    'error_missing_startingposition',
     'error_missing_stream',
     'error_multiple_resource_errors',
     'error_s3_not_in_template',