What is Amazon Simple Notification Service (Amazon SNS)
Amazon Simple Notification Service (Amazon SNS) is a web service that coordinates and manages the delivery or sending of messages to subscribing endpoints or clients. Supported endpoints: Lambda, SQS, HTTP/S, Email, SMS.
How Amazon SNS Works
How Amazon SNS Works
How Amazon SNS Works. Source: docs.aws.amazon.dom
Security
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You can enable server-side encryption (SSE) for a topic to protect its data.
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All requests to topics with SSE enabled must use HTTPS and Signature Version 4.
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Use VPC endpoint to keep messages secure and within AWS network (i.e messages do not traverse the internet)
VPC endpoint for SNS
VPC endpoint for SNS
VPC endpoint for SNS. Source: docs.aws.amazon.com/sns
Message Delivery Status
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Whether message was delivered to endpoint
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Determine how long it took from publication till SNS sent message to endpoint
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Identify response by the endpoint
Amazon SNS provides support to log the delivery status of notification messages sent to topics with the following Amazon SNS endpoints:
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Application
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HTTP
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Lambda
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SQS
Message Filtering
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By default, an Amazon SNS topic subscriber receives every message published to the topic. To receive a subset of the messages, a subscriber must assign a filter policy to the topic subscription.
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Filter policy - A simple JSON object containing attributes that define which messages the subscriber receives.
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A subscription filter policy allows you to specify attribute names and assign a list of values to each attribute name. When Amazon SNS evaluates message attributes against the subscription filter policy, it ignores message attributes that aren’t specified in the policy.
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Additions or changes to a subscription filter policy require up to 15 minutes to fully take effect.
Large Payloads
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Amazon SNS and Amazon SQS let you send and receive large payloads (from 64 to 256 kilobytes in size).
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To send large payloads, you must use an AWS SDK that supports Signature Version 4.
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To avoid having Amazon SQS and HTTP/S endpoints process the JSON formatting of messages, Amazon SNS also allows raw message delivery
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When you enable raw message delivery for an Amazon SQS endpoint, any Amazon SNS metadata is stripped from the published message and the message is sent as is.
Monitoring and Logging
AWS X-Ray- You can use X-Ray with Amazon SNS to trace and analyze the
messages that travel through your application.
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CloudTrail- captures API calls for Amazon SNS as events. -
CloudWatch- integrates with Amazon SNS. For example, you can set an alarm to send you an email notification if a specified threshold is met for an Amazon SNS metric, such as NumberOfNotificationsFailed.
General Notes
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A dead-letter queue is an Amazon SQS queue that an Amazon SNS subscription can target for messages that can’t be delivered to subscribers successfully.
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10- The maximum number of attributes a message can have.