Register service with Consul using Consul API

There are many ways to register a service with Consul such as using a configuration file, using Consul API, … In this tutorial, I will guide you how to use Consul API to register a service with Consul!

First, I will create a simple service with Spring Boot with Spring Web dependency:

expose a simple endpoint like “/hello”:

package com.huongdanjava.consul;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

@SpringBootApplication
@RestController
public class ConsulServiceRegisterServiceExampleApplication {

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

  @GetMapping("/hello")
  public String hello() {
    return "Hello from Huong Dan Java";
  }

}

package com.huongdanjava.consul;

import org.springframework.boot.SpringApplication;

import org.springframework.boot.autoconfigure.SpringBootApplication;

import org.springframework.web.bind.annotation.GetMapping;

import org.springframework.web.bind.annotation.RestController;

@SpringBootApplication

@RestController

public class ConsulServiceRegisterServiceExampleApplication {

public static void main(String[] args) {

SpringApplication.run(ConsulServiceRegisterServiceExampleApplication.class, args);

}

@GetMapping("/hello")

public String hello() {

return "Hello from Huong Dan Java";

}

Run this Spring Boot application and request to http://localhost:8080/hello, you will see the following result:

Now, let’s register this service with Consul!

To register a service with Consul, you can use the Register Service API at https://developer.hashicorp.com/consul/api-docs/agent/service#register-service. Basically, you can request with the PUT method to Consul’s address http://localhost:8500/v1/agent/service/register with data in the request body, for my example, as follows:

{
    "Name": "huongdanjava-service",
    "Address": "host.docker.internal",
    "Port": 8080
}

{

"Name": "huongdanjava-service",

"Address": "host.docker.internal",

"Port": 8080

}

Name is the name of the service
Address is the hostname of the service. Here, I ran Consul using Docker Compose, and my service is running on the host machine, so as you can see, the address information will be host.docker.internal.
Port is the port where the service is running

For my example, I only declare some basic information as above. Depending on the case, please see more data requests that Consul supports in the link above!

The result when I run the above request with Postman is as follows: