Merge pull request #1667 from iainb/enforce-message-size

SNS - Enforce 'Message too long' exception when publishing messages

moto/sns/models.py

@@ -24,6 +24,7 @@ from .utils import make_arn_for_topic, make_arn_for_subscription
 
 DEFAULT_ACCOUNT_ID = 123456789012
 DEFAULT_PAGE_SIZE = 100
+MAXIMUM_MESSAGE_LENGTH = 262144  # 256 KiB
 
 
 class Topic(BaseModel):
@@ -327,6 +328,9 @@ class SNSBackend(BaseBackend):
             # Note that the AWS docs around length are wrong: https://github.com/spulec/moto/issues/1503
             raise ValueError('Subject must be less than 100 characters')
 
+        if len(message) > MAXIMUM_MESSAGE_LENGTH:
+            raise InvalidParameterValue("An error occurred (InvalidParameter) when calling the Publish operation: Invalid parameter: Message too long")
+
         try:
             topic = self.get_topic(arn)
             message_id = topic.publish(message, subject=subject,

tests/test_sns/test_publishing_boto3.py

@@ -10,6 +10,7 @@ import sure  # noqa
 
 import responses
 from botocore.exceptions import ClientError
+from nose.tools import assert_raises
 from moto import mock_sns, mock_sqs
 
 
@@ -308,6 +309,20 @@ def test_publish_subject():
         raise RuntimeError('Should have raised an InvalidParameter exception')
 
 
+@mock_sns
+def test_publish_message_too_long():
+    sns = boto3.resource('sns', region_name='us-east-1')
+    topic = sns.create_topic(Name='some-topic')
+
+    with assert_raises(ClientError):
+        topic.publish(
+            Message="".join(["." for i in range(0, 262145)]))
+
+    # message short enough - does not raise an error
+    topic.publish(
+        Message="".join(["." for i in range(0, 262144)]))
+
+
 def _setup_filter_policy_test(filter_policy):
     sns = boto3.resource('sns', region_name='us-east-1')
     topic = sns.create_topic(Name='some-topic')