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Each message will have a "one-click unsubscribe" footer, facilitating update of the recipient's notification settings to suppress email delivery.
Leveraging the Synapse
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Messaging System
Synapse has an existing system for sending messages, described here: Messaging services. This service requires the client to upload the body of an email to an S3 file, then create a message object referencing the file and containing other metadata (from, to, subject). We will leverage this by adding a component which receives emails and converts them to web requests. The service we have investigated for this purpose is http://www.cloudmailin.com/. CloudMailIn has an option to format requests as JSON, http://docs.cloudmailin.com/http_post_formats/json/
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