# Polaris Discovery example

## Example Introduction

The examples will explain how to use ```spring-cloud-starter-tencent-polaris-discovery`` in Spring Cloud project for its features.

This example is divided to two microservice, discovery-caller-service and discovery-callee-service. In these two microservices, discovery-caller-service invokes discovery-callee-service.

## Instruction

### Configuration

```src/main/resources``` and ```bootstrap.yml``` of two micro-services add the following instructions. ${ip} and ${port} are Polaris backend IP address and port number.

```yaml
spring:
  application:
    name: ${application.name}
  cloud:
    polaris:
      server-addr: ${ip}:${port}
```

### Launching Example

#### Launching Polaris Backend Service

Reference to [Polaris](https://github.com/polarismesh)

#### Launching Application

- IDEA Launching

Launching ```spring-cloud-tencent-examples/polaris-discovery-example/discovery-caller-service```'s  ``DiscoveryCallerService``` and ``spring-cloud-tencent-examples/polaris-discovery-example/discovery-callee-service```'s ```DiscoveryCalleeService``

- Maven Package Launching

Execute under ```spring-cloud-tencent-examples/polaris-discovery-example```

```sh
mvn clean package
```

Then at ```discovery-caller-service``` and ```discovery-callee-service``` find the package that generates jar, and run it

```
java -jar ${app.jar}
```

Launch application, change ${app.jar} to jar's package name

### Verify

#### Feign Invoke

Execute the following orders to invoke Feign, ```DiscoveryCalleeService``` goes bank to the sum of value1+value2

```shell
curl -L -X GET 'http://localhost:48080/discovery/service/caller/feign?value1=1&value2=2'
```

Expected return rate

```
3
```

#### RestTemplate Invoke

Execute the following orders to invoke RestTemplate, ```DiscoveryCalleeService``` goes back to string characters

```shell
curl -L -X GET 'http://localhost:48080/discovery/service/caller/rest'
```

Expected return rate

```
Discovery Service Callee
```