使用最新的版本，按照教程制作demo遇到的一些问题

环境：
- JDK版本：17.0.1 2021-10-19 LTS
- SpringBoot版本：2.6.6
- retrofit-spring-boot-starter版本：2.2.21
- sentinel-core版本：1.8.3
出现的几个问题：
1. 在定义外部接口调用中，注释RetrofitClient的 **path** 参数好像并没有作用
例如我的代码：

```
@RetrofitClient(baseUrl = "${third.a.baseUrl}",  path = "/api/a" , poolName = "a", fallbackFactory = ThirdAApiFallbackFactory.class)
@Intercept(handler = TimestampInterceptor.class, include = {"/api/**"}, exclude = {"/api/a/exclude"})
@Degrade(count = 1, degradeStrategy = DegradeStrategy.EXCEPTION_RATIO)
public interface ThirdAApi {

@GET("/include")
    Msg<Person> get(@Query("id") Long id);

@POST("/exclude")
    Msg<String> add(@Body Person person);

@GET("/degrade")
    Msg<String> degrade();
}
```
当我调用 **get** 、 **add** 、 **degrade** 时，按照正常的逻辑来讲，应该是调用第三方的 **/api/a/include** 、 **/api/a/exclude** 、 **/api/a/degrade** 这三个接口，但是实际上通过日志可以看到调用的是 **/include** 、 **/exclude** 和 **/degrade** ，这个path在这里没有发挥它的作用

2. 无论是fallbackFactory还是fallback都没有在demo中正确运行，首先说 **fallback** ， **fallback的参数是一个实现了API接口的类，并且为spring的bean** ，当我这样做了之后，spring在启动的时候直接就失败了，原因是接口的实现有多个，我的demo代码如下：
pom配置：

```
<dependency>
   <groupId>com.github.lianjiatech</groupId>
   <artifactId>retrofit-spring-boot-starter</artifactId>
   <version>2.2.21</version>
</dependency>
<dependency>
   <groupId>com.alibaba.csp</groupId>
   <artifactId>sentinel-core</artifactId>
   <version>1.8.3</version>
</dependency>
```
application.yml中的配置：

```
retrofit:
  degrade:
    # 是否启用熔断降级
    enable: true
    # 熔断降级实现方式 目前只有 sentinel
    degrade-type: sentinel
    # 熔断资源名称解析器
    resource-name-parser: com.github.lianjiatech.retrofit.spring.boot.degrade.DefaultResourceNameParser
```
API接口申明：

```
@RetrofitClient(baseUrl = "${third.b.baseUrl}", fallback = ThirdBApiFallback.class, poolName = "b")
@Sign(accessKey = "testAccessKey", secretKey = "testSecretKey", include = {"/api/**"}, exclude = {"/api/b/exclude/**"})
@Degrade(count = 3, degradeStrategy = DegradeStrategy.EXCEPTION_RATIO)
public interface ThirdBApi {

@GET("/api/b/include")
    Msg<Person> get(@Query("id") Long id);

@DELETE("/api/b/exclude/{id}")
    Msg<String> del(@Path("id") Long id);
}
```
API接口熔断降级的实现类：

```
@Component
public class ThirdBApiFallback implements ThirdBApi {
    @Override
    public Msg<Person> get(Long id) {
        Msg<Person> msg = new Msg<>();
        msg.setCode(-100);
        msg.setMsg("连接错误");
        return msg;
    }

@Override
    public Msg<String> del(Long id) {
        Msg<String> msg = new Msg<>();
        msg.setCode(-100);
        msg.setMsg("连接错误");
        return msg;
    }
}
```
demo启动日志：

```
Caused by: org.springframework.beans.factory.NoUniqueBeanDefinitionException: No qualifying bean of type 'com.example.retrofitdemo.api.ThirdBApi' available: expected single matching bean but found 2: thirdBApiFallback,thirdBApi
```

其次再说 **fallbackFactory** ，pom.xml和applicaiton.yml中的配置和上面一样，启动不会报错，但是熔断没有降级，demo代码如下
接口API：

```
@RetrofitClient(baseUrl = "${third.a.baseUrl}", poolName = "a", fallbackFactory = ThirdAApiFallbackFactory.class)
@Intercept(handler = TimestampInterceptor.class, include = {"/api/**"}, exclude = {"/api/a/exclude"})
@Degrade(count = 1, degradeStrategy = DegradeStrategy.EXCEPTION_RATIO)
public interface ThirdAApi {

@GET("/api/a/include")
    Msg<Person> get(@Query("id") Long id);

@POST("/api/a/exclude")
    Msg<String> add(@Body Person person);

@GET("/api/a/degrade")
    Msg<String> degrade();
}
```

fallbackFactory:

```
@Slf4j
@Component
public class ThirdAApiFallbackFactory implements FallbackFactory<ThirdAApi> {
    @Override
    public ThirdAApi create(Throwable cause) {
        log.error("接口A熔断:{} - {}", cause.getMessage(), cause);
        return new ThirdAApi() {
            @Override
            public Msg<Person> get(Long id) {
                return msg();
            }

@Override
            public Msg<String> add(Person person) {
                return msg();
            }

@Override
            public Msg<String> degrade() {
                return msg();
            }

public <T> Msg<T> msg() {
                Msg<T> msg = new Msg<>();
                msg.setCode(-2);
                msg.setMsg("服务降级处理");
                return msg;
            }
        };
    }
}
```
在这里，ThirdAApi申明的degrade这个接口在第三方是没有这个接口的，也就是说第三方是没有/api/a/degrade这个API，但是我这里申明了，只是为了测试熔断降级功能，调用之后发现并没有走到熔断降级方法中，调用日志如下：

```
Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is com.github.lianjiatech.retrofit.spring.boot.exception.RetrofitException: invalid Response! request=Request{method=GET, url=http://127.0.0.1:8080/api/a/degrade, tags={class retrofit2.Invocation=com.example.retrofitdemo.api.ThirdAApi.degrade() []}}, response=Response{protocol=http/1.1, code=404, message=, url=http://127.0.0.1:8080/api/a/degrade?timestamp=1649302719168}, body={"timestamp":"2022-04-07T03:38:39.563+00:00","status":404,"error":"Not Found","path":"/api/a/degrade"}] with root cause
```
调用接口返回：

```
{
    "timestamp": "2022-04-07T03:38:39.574+00:00",
    "status": 500,
    "error": "Internal Server Error",
    "path": "/call/aDegrade"
}
```

希望作者能看到并指点下到底是我什么地方配置的有问题，我相信这个功能应该是完整的并且是没有问题的

lianjiatech/retrofit-spring-boot-starter

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