A message blaster hosted by FiftyFiftyOneArizona
This is an in-house solution built by our webmaster to handle message blasts (mass messaging people with updates).
It is built allowing support for multiple channels so that other groups could have their own set of subscribers. It also seamlessly supports an arbitrary amount of transport methods. Currently, this system only supports Signal but it can be expanded to seamlessly include SMS and others.
About This System
This section contains information about various data structures the system uses. Please reference the source code as linked for each term if you want a more precise explanation. It is designed to have as few moving parts as possible and have stable, reliable behavior during power loss & interruptions.
A rough UML class diagram showing each object running on the system
Red boxes are data structures, the blue box is a Go interface, and the black boxes are more class-like objects.
Represents a “topic” (or similar) that users can subscribe to.
Represents a Channel-Subscriber pair.
Represents a string of text sent to a channel.
Provides a simple interface on top of one end transport system (Signal, SMS, etc.)
Handles caching finalized outgoing messages in order to enforce a rate limit on top of the Postman interface.
Effectively a map between a string and a Box. It abstracts away each individual box object into a string that each Subscriber holds.
Takes incoming messages and responds to them. It is what the users interact with when subscribing, unsubscribing, etc.
Handles ensuring that if one part of a blast is sent, all of it is sent. This object handles the main algorithm for ensuring consistent behavior.
Provides an interface on top of a persistent database to store subscriptions.
Used by the Bot to enforce what channels users are allowed to subscribe to.
Used by the Bot to enforce what subscribers (which users) are allowed to send blasts on which channels.