Serverless App Engine:Build service gateways

Step 1: Create the Maven project

Create a Maven project named spring-cloud-gateway-nacos and add the following to pom.xml:

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>2.1.4.RELEASE</version>
    <relativePath/>
</parent>

<dependencies>
    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-gateway</artifactId>
    </dependency>
    <dependency>
        <groupId>com.alibaba.cloud</groupId>
        <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
        <version>2.1.1.RELEASE</version>
    </dependency>
</dependencies>

<dependencyManagement>
    <dependencies>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-dependencies</artifactId>
            <version>Greenwich.SR1</version>
            <type>pom</type>
            <scope>import</scope>
        </dependency>
    </dependencies>
</dependencyManagement>

<build>
    <plugins>
        <plugin>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-maven-plugin</artifactId>
        </plugin>
    </plugins>
</build>

Step 2: Create the startup class

Create a class named GatewayApplication:

@SpringBootApplication
@EnableDiscoveryClient
public class GatewayApplication {
    public static void main(String[] args) {
        SpringApplication.run(GatewayApplication.class, args);
    }
}

Step 3: Configure the gateway

Add the following to application.yaml. The routes section defines how the gateway forwards requests: all requests prefixed with /provider1/ are routed to the service-provider backend, with the /provider1 prefix stripped before forwarding.

Replace 127.0.0.1:8848 with your Nacos Server address if it runs on a different host.

server:
  port: 18012

spring:
  application:
    name: spring-cloud-gateway-nacos
  cloud:
    gateway:
      routes:
        - id: service-provider
          uri: lb://service-provider          # Route to service-provider via load balancing
          predicates:
            - Path=/provider1/**
          filters:
            - StripPrefix=1                   # Strip the /provider1 prefix before forwarding
    nacos:
      discovery:
        server-addr: 127.0.0.1:8848

Step 4: Create a service provider

The gateway needs a backend service to forward requests to. For a complete example, see Migrate Spring Cloud applications to SAE.

A minimal service provider looks like this:

@SpringBootApplication
@EnableDiscoveryClient
public class ProviderApplication {

    public static void main(String[] args) {
        SpringApplication.run(ProviderApplication.class, args);
    }

    @RestController
    public class EchoController {
        @RequestMapping(value = "/echo/{string}", method = RequestMethod.GET)
        public String echo(@PathVariable String string) {
            return string;
        }
    }
}

Verify the gateway

Local verification

Start both the gateway and the service provider, then send a test request:

curl http://127.0.0.1:18012/provider1/echo/hello

Expected output:

hello

The gateway strips the /provider1 prefix and forwards /echo/hello to the service-provider backend.

To confirm the gateway registered with Nacos, log in to the Nacos console at http://127.0.0.1:8848/nacos (default credentials: nacos/nacos). Go to Service Management > Services and verify that spring-cloud-gateway-nacos appears in the list. You can also view detailed service information by clicking Details.

Verify in SAE

Deploy the application to SAE. SAE automatically updates the Nacos connection details—IP address, service port, namespace, AccessKey ID, AccessKey secret, and context path. No additional configuration is needed. Your existing local Nacos settings can be retained or removed.

Step 1: Create the Maven project

Create a Maven project named spring-cloud-zuul-nacos and add the following to pom.xml:

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>2.1.4.RELEASE</version>
    <relativePath/>
</parent>

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-webflux</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-netflix-zuul</artifactId>
    </dependency>
    <dependency>
        <groupId>com.alibaba.cloud</groupId>
        <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
        <version>2.1.1.RELEASE</version>
    </dependency>
</dependencies>

<dependencyManagement>
    <dependencies>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-dependencies</artifactId>
            <version>Greenwich.SR1</version>
            <type>pom</type>
            <scope>import</scope>
        </dependency>
    </dependencies>
</dependencyManagement>

<build>
    <plugins>
        <plugin>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-maven-plugin</artifactId>
        </plugin>
    </plugins>
</build>

Step 2: Create the startup class

Create a class named ZuulApplication:

@SpringBootApplication
@EnableZuulProxy
@EnableDiscoveryClient
public class ZuulApplication {
    public static void main(String[] args) {
        SpringApplication.run(ZuulApplication.class, args);
    }
}

Step 3: Configure the gateway

Add the following to application.properties. The zuul.routes entries define routing rules: requests prefixed with /provider1/ are forwarded to the service-provider backend service.

Replace 127.0.0.1:8848 with your Nacos Server address if it runs on a different host.

spring.application.name=spring-cloud-zuul-nacos
server.port=18022

spring.cloud.nacos.discovery.server-addr=127.0.0.1:8848

zuul.routes.opensource-provider1.path=/provider1/**
zuul.routes.opensource-provider1.serviceId=service-provider

Step 4: Create a service provider

Use the same service provider as the Spring Cloud Gateway example. For details, see Migrate Spring Cloud applications to SAE.

Verify the gateway

Local verification

Start both the Zuul gateway and the service provider, then send a test request:

curl http://127.0.0.1:18022/provider1/echo/hello

Expected output:

hello

To confirm the gateway registered with Nacos, log in to the Nacos console at http://127.0.0.1:8848/nacos (default credentials: nacos/nacos). Go to Service Management > Services and verify that spring-cloud-zuul-nacos appears in the list. You can also view detailed service information by clicking Details.

Verify in SAE

Deploy the application to SAE. SAE automatically updates the Nacos connection details—IP address, service port, namespace, AccessKey ID, AccessKey secret, and context path. No additional configuration is needed. For deployment steps, see Migrate Spring Cloud applications to SAE.