checkoutservice

Checkout Service

The checkout service gets called when the user confirms the checkout request. This service represents an intermediate coordination service between several services. The PlaceOrder remote function will be called upon the checkout request. It will call the Cart Service to get the products of the cart in the user's account. Then it will match those products with Catalog Service and call the Currency Service to convert the prices to the user's preferred currency. Then it calls Shipping Service to get the shipping quote and it converts the shipping cost to the user's preferred currency using the Currency Service. Then the service calculates the total cost and calls the Payment Service so it would be charged from the card and it returns a transaction id. Then we ship the order using the Shipping Service then clear the cart of the user using the Cart Service. Finally, we send an email with all the details to the user's email using Email Service and return the order summary to the caller.

configurable string cartHost = "localhost";

service "CheckoutService" on new grpc:Listener(9094) {
    final CartServiceClient cartClient;
    ...

    function init() returns error? {
        self.cartClient = check new ("http://" + cartHost + ":9092");
        ...
    }

    remote function PlaceOrder(stubs:PlaceOrderRequest request) returns stubs:PlaceOrderResponse|grpc:Error|error {
        ...
    }
    
    ...
}