stakater-nordmart-gateway

Overview

A Spring Cloud Gateway application that aggregates API calls to backend services by providing a condensed REST API for front-end

Spring Cloud Gateway

There are 2 approaches for defining routing, doing it in code or defining it in application.yaml/application.properties. We went with having everything in configuration file. A sample configuration would look something like this

routes:
- id: catalogService
  uri: http://localhost:8080
  predicates:
  - Path=/api/products/**

1. id: Unique id of route
2. uri: Hostname/path where api is running. Eg, http://localhost:8080 or http://catalog.nordmart-dev-apps.svc.cluster.local:8080
3. predicates: Condition on which routing will take place to uri/route. Eg, /api/products/** this will redirect all requests containing /api/products/ URI. Summary: http://gateway-svc:8080/api/products/get-products will be redirected to http://localhost:8080/api/products/get-products

Configurations

Environment variables can be provided to configure the gateway.

Service configurations

• CUSTOMER_API_HOST - Customer service API host.
• CUSTOMER_API_PORT - Customer service API port.
• CATALOG_API_HOST - Catalog service API host.
• CATALOG_API_PORT - Catalog service API port.
• INVENTORY_API_HOST - Inventory service API host.
• INVENTORY_API_PORT - Inventory service API port.
• CART_API_HOST - Cart service API host.
• CART_API_PORT - Cart service API port.
• HTTP_PORT - Port of the gateway service.

Dependencies

It requires following things to be installed:

• Java: ^8.0
• Spring boot 2.2.2.RELEASE
• Maven

Deployment strategy

Local deployment

To run the application locally use the command given below:

mvn spring-boot:run

Docker

To deploy app inside a docker container

• Create a network if it doesn't already exist by executing

  docker network create --driver bridge nordmart-apps

• Build jar file of the app by executing

  mvn clean package

• Next build the image using

  docker build -t gateway .

• Finally run the image by executing

  docker run -d --name gateway --network nordmart-apps -p 8083:8080 -e CART_API_HOST=cart -e CART_API_PORT=8082 -e CATALOG_API_HOST=catalog -e CATALOG_API_PORT=8080 -e INVENTORY_API_HOST=inventory -e INVENTORY_API_PORT=8081 -e PRODUCT_SEARCH_API_HOST=search -e PRODUCT_SEARCH_API_PORT=8084 -e CUSTOMER_API_HOST=customer -e CUSTOMER_API_PORT=8085 -e HTTP_PORT=8080 gateway

Helm Charts

Pre-requisites

Helm operator needs to to be running inside the cluster. Helm operator is deployed by Stakater Global Stack, deployment guidelines are provided in this link

Helm chart deployment

To create helm release of this application using the command given below:

kubectl apply -f helm-release.yaml -n