Merge pull request #4 from badass-techie/feature/create-payment-micro…

…service

Create payment microservice

.env.example

@@ -3,9 +3,14 @@ DISCOVERY_SERVER_HOST=discovery-server
 IDENTITY_DB_URL=jdbc:postgresql://identity-db:5432/identity
 IDENTITY_DB_USERNAME=
 IDENTITY_DB_PASSWORD=
+MPESA_BUSINESS_SHORTCODE=
+MPESA_CONSUMER_KEY=
+MPESA_CONSUMER_SECRET=
+MPESA_PASSKEY=
 ORDER_DB_URL=jdbc:postgresql://order-db:5432/order
 ORDER_DB_USERNAME=
 ORDER_DB_PASSWORD=
 PRODUCT_DB_URL=mongodb://product-db:27017/product
 RABBITMQ_BASE=amqp://rabbitmq:5672
+STRIPE_SECRET_KEY=
 ZIPKIN_BASE=http://zipkin:9411

Dockerfile

@@ -80,3 +80,26 @@ COPY --from=0 /build/Product/target/product-1.0-SNAPSHOT.jar product.jar
 
 # Run the jar file
 ENTRYPOINT ["java","-jar","product.jar"]
+
+
+# Payment
+# Use lightweight python image as base image
+FROM python:3.10-alpine AS payment
+
+# make sure all messages always reach console
+ENV PYTHONUNBUFFERED=1
+
+# prevent writing bytecode
+ENV PYTHONDONTWRITEBYTECODE=1
+
+# Copy the entire python project
+COPY Payment /Payment
+
+# Set working directory
+WORKDIR /Payment
+
+# Install dependencies
+RUN pip install -r requirements.txt
+
+# Run the python file
+ENTRYPOINT ["python", "app.py"]

Dockerfile.dev

@@ -19,3 +19,19 @@ WORKDIR /app
 
 # Build all maven modules
 RUN mvn clean install -DskipTests
+
+
+# This image is used to build the payment microservice
+FROM python:3.10-slim AS payment
+
+# make sure all messages always reach console
+ENV PYTHONUNBUFFERED=1
+
+# prevent writing bytecode
+ENV PYTHONDONTWRITEBYTECODE=1
+
+COPY Payment /app
+
+WORKDIR /app
+
+RUN pip install -r requirements.txt

Order/src/main/java/com/badasstechie/order/config/RabbitMQConfig.java

@@ -1,7 +1,7 @@
 package com.badasstechie.order.config;
 
-import org.springframework.amqp.rabbit.connection.ConnectionFactory;
 import org.springframework.amqp.core.*;
+import org.springframework.amqp.rabbit.connection.ConnectionFactory;
 import org.springframework.amqp.rabbit.core.RabbitTemplate;
 import org.springframework.amqp.support.converter.Jackson2JsonMessageConverter;
 import org.springframework.amqp.support.converter.MessageConverter;
@@ -14,15 +14,28 @@ public class RabbitMQConfig {
     @Value("${message-bus.exchange-name}")
     private String exchangeName;
 
-    @Value("${message-bus.queue-name}")
-    private String queueName;
+    @Value("${message-bus.queues.update-stock}")
+    private String updateStockQueueName;
+
+    @Value("${message-bus.queues.order-awaiting-payment}")
+    private String orderAwaitingPaymentQueueName;
 
-    @Value("${message-bus.routing-key}")
-    private String routingKey;
+    @Value("${message-bus.queues.order-payment-processed}")
+    private String orderPaymentProcessedQueueName;
+
+    @Bean
+    public Queue updateStockQueue() {
+        return new Queue(updateStockQueueName);
+    }
 
     @Bean
-    public Queue queue() {
-        return  new Queue(queueName);
+    public Queue orderAwaitingPaymentQueue() {
+        return new Queue(orderAwaitingPaymentQueueName);
+    }
+
+    @Bean
+    public Queue orderPaymentProcessedQueue() {
+        return new Queue(orderPaymentProcessedQueueName);
     }
 
     @Bean
@@ -31,22 +44,42 @@ public TopicExchange exchange() {
     }
 
     @Bean
-    public Binding binding(Queue queue, TopicExchange exchange) {
-        return BindingBuilder
-                .bind(queue)
-                .to(exchange)
-                .with(routingKey);
+    public Binding updateStockBinding(Queue updateStockQueue, TopicExchange exchange) {
+        return BindingBuilder.bind(updateStockQueue).to(exchange).with(updateStockQueueName);
     }
 
     @Bean
-    public MessageConverter messageConverter() {
-        return  new Jackson2JsonMessageConverter();
+    public Binding orderAwaitingPaymentBinding(Queue orderAwaitingPaymentQueue, TopicExchange exchange) {
+        return BindingBuilder.bind(orderAwaitingPaymentQueue).to(exchange).with(orderAwaitingPaymentQueueName);
+    }
+
+    @Bean
+    public Binding orderPaymentProcessedBinding(Queue orderPaymentProcessedQueue, TopicExchange exchange) {
+        return BindingBuilder.bind(orderPaymentProcessedQueue).to(exchange).with(orderPaymentProcessedQueueName);
     }
 
     @Bean
-    public AmqpTemplate template(ConnectionFactory connectionFactory) {
+    public MessageConverter messageConverter() {
+        return new Jackson2JsonMessageConverter();
+    }
+
+    @Bean AmqpTemplate updateStockTemplate(ConnectionFactory connectionFactory) {
+        return createTemplate(connectionFactory, updateStockQueueName);
+    }
+
+    @Bean AmqpTemplate orderAwaitingPaymentTemplate(ConnectionFactory connectionFactory) {
+        return createTemplate(connectionFactory, orderAwaitingPaymentQueueName);
+    }
+
+    @Bean AmqpTemplate orderPaymentProcessedTemplate(ConnectionFactory connectionFactory) {
+        return createTemplate(connectionFactory, orderPaymentProcessedQueueName);
+    }
+
+    private AmqpTemplate createTemplate(ConnectionFactory connectionFactory, String routingKey) {
         RabbitTemplate template = new RabbitTemplate(connectionFactory);
+        template.setExchange(exchangeName);
+        template.setRoutingKey(routingKey);
         template.setMessageConverter(messageConverter());
-        return  template;
+        return template;
     }
-}
+}

Order/src/main/java/com/badasstechie/order/dto/OrderPaymentRequest.java

@@ -0,0 +1,23 @@
+package com.badasstechie.order.dto;
+
+import java.math.BigDecimal;
+import java.util.Map;
+
+/**
+ * This is a record class that represents an order payment request to be sent to the payment microservice via the message bus and then to the payment gateway.
+ *
+ * @param orderId The order ID.
+ * @param orderNumber The order number.
+ * @param amount Total amount to be paid for in the smallest unit of the currency.
+ * @param currency The currency in which the payment is made.
+ * @param paymentMethod Exactly one of 'stripe', 'paypal', or 'mpesa'.
+ * @param payerDetails A map of payer details. The keys are the names of the fields required by the payment gateway such as 'cardNumber', 'cvc', 'expiryMonth', 'expiryYear', and 'phoneNumber'.
+ */
+public record OrderPaymentRequest(
+        Long orderId,
+        String orderNumber,
+        BigDecimal amount,
+        String currency,
+        String paymentMethod,
+        Map<String, String> payerDetails
+) {}

Order/src/main/java/com/badasstechie/order/dto/OrderPaymentResponse.java

@@ -0,0 +1,15 @@
+package com.badasstechie.order.dto;
+
+import java.math.BigDecimal;
+import java.util.Map;
+
+public record OrderPaymentResponse(
+        Long orderId,
+        String orderNumber,
+        BigDecimal amount,
+        String currency,
+        String paymentMethod,
+        Map<String, String> payerDetails,
+        PaymentResult resultStatus,
+        String resultMessage
+) {}

Order/src/main/java/com/badasstechie/order/dto/OrderRequest.java

@@ -1,8 +1,11 @@
 package com.badasstechie.order.dto;
 
 import java.util.List;
+import java.util.Map;
 
 public record OrderRequest(
     List<OrderItemDto> items,
-    String deliveryAddress
+    String deliveryAddress,
+    String paymentMethod,
+    Map<String, String> payerDetails
 ){}

Order/src/main/java/com/badasstechie/order/dto/PaymentResult.java

@@ -0,0 +1,6 @@
+package com.badasstechie.order.dto;
+
+public enum PaymentResult {
+    SUCCESS,
+    FAILED
+}

Order/src/main/java/com/badasstechie/order/model/OrderStatus.java

@@ -1,7 +1,7 @@
 package com.badasstechie.order.model;
 
 public enum OrderStatus {
-    CREATED,
+    AWAITING_PAYMENT,
     SHIPPING,
     COMPLETED,
     CANCELLED

Order/src/main/java/com/badasstechie/order/service/OrderService.java

@@ -1,9 +1,6 @@
 package com.badasstechie.order.service;
 
-import com.badasstechie.order.dto.OrderItemDto;
-import com.badasstechie.order.dto.OrderRequest;
-import com.badasstechie.order.dto.OrderResponse;
-import com.badasstechie.order.dto.ProductStockDto;
+import com.badasstechie.order.dto.*;
 import com.badasstechie.order.model.Order;
 import com.badasstechie.order.model.OrderItem;
 import com.badasstechie.order.model.OrderStatus;
@@ -12,37 +9,37 @@
 import com.badasstechie.product.grpc.ProductStocksRequest;
 import com.badasstechie.product.grpc.ProductStocksResponse;
 import io.github.resilience4j.circuitbreaker.annotation.CircuitBreaker;
+import lombok.extern.slf4j.Slf4j;
 import net.devh.boot.grpc.client.inject.GrpcClient;
-import org.springframework.amqp.rabbit.core.RabbitTemplate;
+import org.springframework.amqp.core.AmqpTemplate;
+import org.springframework.amqp.rabbit.annotation.RabbitListener;
 import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.beans.factory.annotation.Value;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.ResponseEntity;
 import org.springframework.stereotype.Service;
 
 import java.math.BigDecimal;
 import java.time.Instant;
-import java.util.List;
-import java.util.UUID;
+import java.util.*;
 
 @Service
+@Slf4j
 public class OrderService {
     private final OrderRepository orderRepository;
-    private final RabbitTemplate rabbitTemplate;
+    private final AmqpTemplate updateStockTemplate, orderAwaitingPaymentTemplate;
 
     @GrpcClient("product-grpc-service")
     private ProductGrpcServiceGrpc.ProductGrpcServiceBlockingStub productGrpcService;
 
-    @Value("${message-bus.exchange-name}")
-    private String messageBusExchangeName;
-
-    @Value("${message-bus.routing-key}")
-    private String messageBusRoutingKey;
+    private final Map<String, List<String>> paymentRequirements = new HashMap<>();
 
     @Autowired
-    public OrderService(OrderRepository orderRepository, RabbitTemplate rabbitTemplate) {
+    public OrderService(OrderRepository orderRepository, AmqpTemplate updateStockTemplate, AmqpTemplate orderAwaitingPaymentTemplate) {
         this.orderRepository = orderRepository;
-        this.rabbitTemplate = rabbitTemplate;
+        this.updateStockTemplate = updateStockTemplate;
+        this.orderAwaitingPaymentTemplate = orderAwaitingPaymentTemplate;
+        paymentRequirements.put("stripe", List.of("cardToken"));
+        paymentRequirements.put("mpesa", List.of("phoneNumber"));
     }
 
     private OrderResponse mapOrderToResponse(Order order) {
@@ -82,6 +79,18 @@ private OrderItemDto mapOrderItemToDto(OrderItem orderItem) {
     }
 
     public ResponseEntity<OrderResponse> placeOrder(OrderRequest orderRequest, Long userId) {
+        // validate the payment details
+        String paymentMethod = orderRequest.paymentMethod();
+        if (!paymentRequirements.containsKey(paymentMethod)) {
+            throw new RuntimeException("Unknown payment method");
+        }
+
+        List<String> requiredFields = paymentRequirements.get(paymentMethod);
+        for (String field : requiredFields) {
+            if (!orderRequest.payerDetails().containsKey(field))
+                throw new RuntimeException(field + " not found but required for " + paymentMethod + " payment");
+        }
+
         List<ProductStockDto> stocks = getProductStocks(orderRequest.items().stream().map(OrderItemDto::productId).toList());
 
         // throw exception if length of stocks and order items are not equal
@@ -100,18 +109,32 @@ public ResponseEntity<OrderResponse> placeOrder(OrderRequest orderRequest, Long
                         .userId(userId)
                         .orderNumber(UUID.randomUUID().toString())
                         .items(orderRequest.items().stream().map(this::mapDtoToOrderItem).toList())
-                        .status(OrderStatus.CREATED)
+                        .status(OrderStatus.AWAITING_PAYMENT)
                         .deliveryAddress(orderRequest.deliveryAddress())
                         .created(Instant.now())
                         .build()
         );
 
-        // publish message to message bus with the product ids and quantities
+        // publish message to message bus for payment to be processed
+        OrderPaymentRequest paymentRequest = new OrderPaymentRequest(
+                order.getId(),
+                order.getOrderNumber(),
+                order.getItems().stream().reduce(
+                        BigDecimal.ZERO,
+                        (subtotal, orderItem) -> subtotal.add(orderItem.getUnitPrice().multiply(BigDecimal.valueOf(orderItem.getQuantity()))),
+                        BigDecimal::add
+                ),
+                "KES",
+                orderRequest.paymentMethod(),
+                orderRequest.payerDetails()
+        );
+        orderAwaitingPaymentTemplate.convertAndSend(paymentRequest);
+
+        // publish message to message bus for stock to be updated
         List<ProductStockDto> productsOrdered = order.getItems().stream()
                 .map(item -> new ProductStockDto(item.getProductId(), item.getQuantity()))
                 .toList();
-
-        rabbitTemplate.convertAndSend(messageBusExchangeName, messageBusRoutingKey, productsOrdered);
+        updateStockTemplate.convertAndSend(productsOrdered);
 
         return new ResponseEntity<>(mapOrderToResponse(order), HttpStatus.CREATED);
     }
@@ -127,6 +150,23 @@ public List<ProductStockDto> getProductStocks(List<String> ids) {
                 .toList();
     }
 
+    // update order status after payment has been processed
+    @RabbitListener(queues = "${message-bus.queues.order-payment-processed}")
+    public void updateOrderStatus(OrderPaymentResponse paymentResponse) {
+        Order order = orderRepository.findById(paymentResponse.orderId())
+                .orElseThrow(() -> new RuntimeException("Order not found"));
+
+        if (paymentResponse.resultStatus() == PaymentResult.SUCCESS) {
+            order.setStatus(OrderStatus.SHIPPING);
+            orderRepository.save(order);
+        } else if (paymentResponse.resultStatus() == PaymentResult.FAILED) {
+            order.setStatus(OrderStatus.CANCELLED);
+            orderRepository.save(order);
+        }
+
+        log.info("Payment processed for order number {}. Result: {}", paymentResponse.orderNumber(), paymentResponse.resultMessage());
+    }
+
     public OrderResponse getOrder(Long id) {
         return orderRepository.findById(id)
                 .map(this::mapOrderToResponse)

Order/src/main/resources/application.yml

@@ -84,9 +84,11 @@ resilience4j:
 
 # custom properties for our message bus
 message-bus:
-  exchange-name: 'eshoponsteroids'  # name of the exchange
-  queue-name: 'new-order' # name of the queue
-  routing-key: 'new-order'  # used to route messages from the exchange to the specified queue
+  exchange-name: 'eshoponsteroids'
+  queues:
+    update-stock: 'update-stock'
+    order-awaiting-payment: 'order-awaiting-payment'
+    order-payment-processed: 'order-payment-processed'
 
 springdoc:
   api-docs: