grocery-delivery-service

Introduction

This repository holds a distributed microservice application for a grocery delivery service that includes the following applications:

1. grocery-delivery-frontend

   • An Angular SPA application

2. GroceryDeliveryAPI

   • .NET 6 API that interacts with the front end application with the following endpoints:
     • GET api/products/{categoryId}
       • Retrieves grocery products from PostgresSQL database by a given category
     • GET api/categories
       • Retrieves all the available categories from the PostgresSQL database
     • GET api/orders
       • Retrieves all the orders that a client has placed
     • POST api/orders
       • Submits a pending grocery delivery through the system and returns an order number

3. Order Confirmation Consumer

   • .NET 6 Background Service Kafka Consumer application that reads from a Kafka Topic for Pending Orders that were placed and sends a confirmation message to the client via a SignalR connection.

4. Grocery Delivery Consumer

   • .NET 6 Background Service Kafka Consumer application that reads from a Kafka Topic for Pending Orders that were placed and calls the Pending Orders gRPC service to schedule a pending order for delivery.

5. Pending Orders Service

   • .NET 6 gRPC service that takes a pending order and inserts it into the database.

6. Delivery Scheduler Consumer

   • .NET 6 Kafka Consumer application that reads messages from a Debezium PostgresSQL Kafka Topic for all the orders that are scheduled for delivery and sets a flag in the database marking an order as delivered.

Architecture:

flowchart LR;
    request <----> products;
    request <----> categories;
    request <----> getOrders;
    request <----> submitOrder;
    products <----> database;
    categories <----> database;
    getOrders <----> database;
    submitOrder --> pendingOrdersTopic;
    pendingOrdersTopic --> kafkaconsumer;
    pendingOrdersTopic --> orderConfirmationConsumer;
    kafkaconsumer <----> pendingOrdersGrpc;
    pendingOrdersGrpc -->|Insert Pending Order| database;
    orderConfirmationConsumer --> request;
    database --> KafkaConnector;
    KafkaConnector --> deliveredOrdersTopic;
    deliveredOrdersTopic --> DeliverySchedulerConsumer;
    DeliverySchedulerConsumer --> database;

    database[(Database)];
    pendingOrdersTopic{Pending Orders Kafka Topic};
    deliveredOrdersTopic{Delivered Orders Kafka Topic};

    subgraph Angular Client;
    request;
    end;
    subgraph GroceryDeliveryAPI;
    products(GET: api/products);
    categories(GET: api/categories);
    getOrders(GET: api/orders);
    submitOrder(POST: api/orders);
    end;
    subgraph GroceryDeliveryConsumer;
    kafkaconsumer(kafka consumer);
    end;
    subgraph PendingOrdersService;
    pendingOrdersGrpc(Pending Orders gRPC Service);
    end;
    subgraph OrderConfirmationConsumer;
    orderConfirmationConsumer(Order Confirmation Kafka Consumer);
    end;
    subgraph KafkaConnector;
    end;
    subgraph DeliverySchedulerConsumer;
    end;

How to Run

Backend

1. With Docker running, navigate to the root folder (grocery-deliver-service) where the docker-compose.yml file is located.
2. Run the following command in the terminal to spin up the backend:

   docker-compose up -d --build
   

Frontend

1. From a terminal, navigate to the following folder grocery-delivery-frontend
2. You must have Angular CLI installed. If you do not, run the following npm command to download it:

   npm install -g @angular/cli
   

3. From within the grocery-delivery-frontent directory, run the following command:

   ng serve -o