Microservices are a software development technique where applications are broken down into smaller, self-contained services that are easier to build, maintain, and scale. Each service is responsible for a specific function and can be developed and deployed independently. This approach allows for greater flexibility and modularity in the development process.

Some key benefits of using microservices include improved scalability, as services can be scaled individually based on demand. This architecture also allows for better fault isolation, as failures in one service do not necessarily affect the entire system. Additionally, microservices promote faster deployments and updates, as changes can be made to individual services without affecting the entire application.

Key Lesson Concepts:

• Microservices are smaller, self-contained services that are easier to build and maintain.
• Each service is responsible for a specific function and can be developed and deployed independently.
• Benefits of using microservices include improved scalability, better fault isolation, and faster deployments and updates.

What We Will Build

The microservice we’ll develop will handle webhook-based notifications from external platforms, such as Google Play. These webhooks will provide subscription-related data (e.g., new subscriptions, updates, or cancellations). Our microservice will process these notifications, validate the incoming data, and forward structured events to a second service, mimicking integration with a marketing analytics platform (a mock service called AudienceGrid in our case)

Here's how it will work:

• Webhook Handling: The microservice will accept incoming POST requests with subscription events. Each event will be parsed and categorized based on its type, such as subscription starts or updates.
• Data Validation and Mapping: Before processing, the incoming data will be validated for accuracy and mapped into a unified format that the downstream service can understand.
• Forwarding and Persistence: Validated events will be forwarded to AudienceGrid’s API, with certain data persisted in a database to maintain a local record of profiles and properties.

Webhook Publishers and Subscribers: How They Work

A webhook is a way for one application (the publisher) to send real-time data to another application (the subscriber). In our project, external platforms like Google Play serve as webhook publishers that send subscription-related data (e.g., subscription started, updated, or canceled) to our microservice, which acts as the webhook subscriber.

Key Concepts:

• Publisher: This is the system that generates the webhook events. For instance, Google Play generates events like subscription start, renewal, or cancellation and sends them as HTTP POST requests to the registered webhook endpoint.
• Subscriber: This is the system that listens for these webhook events. Our Laravel microservice will serve as the subscriber, accepting these incoming HTTP POST requests on a designated endpoint.

Registering the Webhook Subscriber with the Publisher

To receive webhook events, the subscriber (our microservice) must register its endpoint (e.g., /api/webhook) with the publisher. This step typically involves:

1. Providing the Subscriber URL: You configure the webhook endpoint in the publisher's platform, specifying where events should be sent.
2. Verifying the Subscriber: Publishers often verify the subscriber's authenticity through a verification handshake, such as sending a unique token to the endpoint and requiring a response.
3. Configuring Event Types: You can often select the types of events (e.g., subscription started, canceled) you want to receive from the publisher.

How This Works in Our Project

• Webhook Handling: The microservice will expose a POST endpoint (e.g., /api/webhook) to accept incoming events. It will parse and categorize the events based on their type, such as subscription_started or subscription_updated.
• Data Validation and Mapping: After receiving an event, the microservice will validate its payload to ensure it meets the required schema. The data will then be mapped into a structured format for easier processing.
• Forwarding and Persistence: Validated events will be forwarded to our mock service, AudienceGrid, for further processing or analytics. At the same time, user profiles and properties will be stored locally for future reference.