deepsourcecorp/hermes

Open source notification APIs for the masses.

Hermes provides a single unified API for notifications.

Powerful Templating

Hermes aims to support multiple templating frameworks including:

• Mustache templates (✓)
• Go Templates
• Django Templates
• MJML

...and many more.

Support for Messaging Tools

• Slack (✓)
• Microsoft Teams
• Google Chat
• Discord

...and many more.

Support for Issue Tracking Software

• JIRA (✓)
• Linear
• Trello

...and many more.

Immediate Roadmap

• Hermes UI: Set up templates, subscribers and user notification channels
• RabbitMQ and Beanstalkd interface
• gRPC interface

hermes's Issues

Set up event bus.

Set up an event bus for sending events across domains.

Add linear and polynomial backoffs to hermes.

Linear: The base delay time is equal to the attempt count.

Polynomial Time: The base delay time is calculated as:

𝑎^e

where:

𝑎 is the number of unsuccessful attempts that have been made,
𝑒 is the exponent configured for the strategy.

Setup test coverage analyser.

Set up the DeepSource test coverage analyser for the project.

Redial on connection closure events

Go's AMQP library by design does not permit redialing on connection closures out of the box, since a new topology of exchange queue mapping needs to be generated on every reconnection. This necessitates the need for explicitly listening to connection closure events on the NotifyClose() channel to perform redials. The snippet below describes the redialing to the broker backend

for {
  conn, err := amqp.Dial("connection_string")
  notify := conn.NotifyClose(make(chan *amqp.Error)) // channel to receive error events from broker
  ch, err := conn.Channel()
  msgs, err := ch.consume(
    for {
      select { //check connection
        case err = <-notify:
        //work with error
        break // perform reconnection
        case d = <-msgs:
        // work with the message 
      }
    }
  )
}

This is a reliability problem, and as such the implementation for it should be centralized as part of the Dial() method.