m-thirumal/spring-cloud-gateway

Spring cloud gateway with Rate Limiter (Redis) [Service denial], Circuit Breaker (Resilience4J), Load balancing, encryption and decryption, etc.

spring-cloud-gateway

Features:

• Rate Limiter
• Circuit Breaker
• Encryption and Decryption of request and response body
• Google Re-Captcha validation at gateway for all microservices
• TLS/SSL

Prerequisite - To Run the following projects to get the proper result

1. Eureka Server
2. Eureka Client 1 / MicroServices 1
3. Eureka Client 2 / MicroServices 2
4. Redis

To Create jar

mvn clean package -DskipTests=true

Run as jar from terminal

java -jar target/spring-cloud-gateway-0.0.1-SNAPSHOT.jar

Routing and Load balancer

Encryption & Decryption

Encryption of request body and response body is implemented in global filter and in route 2.

f.filter(encryptDecryptFilter.apply(new EncryptDecryptFilter.Config()))

Rate Limiter

i.e Service Denial

Redis is used for rate limiter, which is used for protecting application from API throttling (Service Denial)

Circuit Breaker

Circuit Breaker has three states Closed State, Open State, Half Open State. The image below shows how the flow from one state to another changes.

1. The Circuit Breaker will be in the Closed state when everything is running as expected when failure starts coming it waits until the set threshold limit is reached then goes to Open state.

2. While in Open states no calls will be going to failing remote service until certain wait time, then it goes to Half-Open state, in this stage reduced amount of calls goes to remote service to make sure the calls are successful, IF the calls are responding as expected it will go to Closed state or it goes back to Open state avoiding calls to failing remote service.

Google Recaptcha

Google Recaptcha can be verified at gateway instead of verifying it in each microservices. Avoid code duplication

TLS/SSL

To Enable SSL, add the following properties in the yml file and add the certificate in .p12 format

server:
  port: 9095
  ssl: 
    enabled: true
    key-store: classpath:keystore.p12
    key-store-password: thirumal
    key-store-type: PKCS12
    key-alias: gateway
  compression:
    enabled: true

Get free SSL certificate from Let's Encrypt

To Generate the .p12 from .pem use the following commands

openssl pkcs12 -export -in fullchain1.pem -inkey privkey1.pem -out keystore.p12 -name gateway -CAfile chain1.pem -caname root