Notifications service

A repository with a service for managing notifications to users. This repository is part of Microservice Reference Framework.

Project structure

Service architecture

---
title: "Layers of the notifications service"
---
classDiagram
    class transport["Transport layer"]
    click transport href "https://github.com/MichalMoudry/mrf-workflow-service/tree/main/transport" "Go to transport layer package"
    class service["Service layer"]
    class database["Persistance layer"]
    transport <-- service
    service <-- database

    note for transport "validates requests\nparses request content\ncontains HTTP middleware\nrequest & response contracts"
    note for service "contains business logic\nhandles commiting transactions\nhandles rolling back of transactions\n..."
    note for database "contains migrations\ncontains SQL queries\ncontains repositories\nhelps with DB transaction\n..."

Diagram catalog:

• Transport layer - Is a layer responsible to handling incoming HTTP requests. This means having functionality for unmarshalling request bodies, validating request data or validating JSON Web Tokens (JWTs).
• Service layer - This layer contains all the business logic of this service. This can include constructing all the queries in a database transaction, publishing event to a message queue or realizing calculations on a set of data.
• Persistance layer - This layer is only responsible for dealing with a database. This includes sending SQL queries to a database and retrieving responses, opening a connection to the database or providing functions for starting or commiting transactions.

Deployment

This section contains information about notifications service's deployment process and environment.

Deployment process

This sub-section describes the deployment process of this service.

---
title: "Deployment of the notifications service"
---
graph TB
    start(GitHub Action trigger)
    start -- Workflow is\nmanually triggered --> manual_deploy
    start -- New tag\nis created --> version_deploy
    manual_deploy{{Manual deployment}}
    version_deploy{{New version}}

    container_registery(Container\nregistery)
    manual_deploy -- Container image is\ncreated from the\napp's source code --> container_registery
    version_deploy -- Container image is\ncreated from the\napp's source code --> container_registery

    azure(Azure Container Apps)
    container_registery -- App's instance\nis created from\nthe image --> azure

    db_migration(Database migration)
    azure --> |Database scheme\nis migrated| db_migration

Diagram catalog:

• GitHub Action trigger - Starting point of the deployment process is a GitHub action for deploying the notifications service. This action is triggered manually or when a new version/tag is created.
• Manual deployment - An event that represents a manual deployment of the notifications service.
• New version - An event representing an automatic deployment of the notifications service. This event is triggered when a new version/tag has been created.
• Container registry - A registry for storing container images.
  • Examples: Docker hub or Azure Container Registry.
• Azure Container Apps - A cloud environment where this service is being hosted/deployed. This environment has Dapr as a serverless service.
• Database migration - There is a mechanism for migrating database scheme to a new version. This service uses so called init container to migrate the database.

Used technologies

Used patterns

User libraries