@FeignClient 實現簡便http請求封裝方式

Posted on by

@FeignClient實現http請求封裝

我們一般在代碼中調用http請求時，都是封裝瞭http調用類，底層自己定義請求頭，在寫的時候，也是需要對返回的值進行json解析，很不方便。

  • name：name屬性會作為微服務的名稱，用於服務發現
  • url：host的意思，不用加http://前綴
  • decode404：當發生http 404錯誤時，如果該字段位true，會調用decoder進行解碼，否則拋出FeignException

使用流程

(1)創建接口類(FeignApi)，來統一規范需要調用的第三方接口

@FeignClient(name = "aaa", url = "localhost:8080", decode404 = true)
public interface FeignApi {
    /**
     * http請求
     */
    @PostMapping("/api/xxxx/baiduaaa")
    ResponseResult<ResponseVo> getSomeMoneyForYourSelfAAA(@RequestBody AAAParam param);
    
    /**
     * 模仿上面寫的Get方式請求
     */
    @GetMapping("/api/xxxx/baidubbb")
    ResponseResult<ResponseVo> getSomeMoneyForYourSelfBBB(@RequestBody AAAParam param);
}

(2)在啟動類加上註解，會去掃包註冊Bean

@EnableFeignClients(basePackages = {"com.aaa"})

(3)業務代碼調用處：

ResponseResult<ResponseVo> response = pmsFeignApi.getSomeMoneyForYourSelfAAA(param);

將http請求封裝為FeignClient

1.配置攔截器

import java.io.IOException;
import java.io.InterruptedIOException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import okhttp3.Interceptor;
import okhttp3.Request;
import okhttp3.Response;
public class OkHttpRetryInterceptor implements Interceptor {undefined
    private static final Logger LOGGER = LoggerFactory.getLogger(OkHttpRetryInterceptor.class);
    /**
     * 最大重試次數
     */
    private int                 executionCount;
    /**
     * 重試的間隔
     */
    private long                retryInterval;
    OkHttpRetryInterceptor(Builder builder) {undefined
        this.executionCount = builder.executionCount;
        this.retryInterval = builder.retryInterval;
    }
    @Override
    public Response intercept(Chain chain) throws IOException {undefined
        Request request = chain.request();
        Response response = doRequest(chain, request);
        int retryNum = 0;
        while ((response == null || !response.isSuccessful()) && retryNum <= executionCount) {undefined
            LOGGER.info("intercept Request is not successful - {}", retryNum);
            final long nextInterval = getRetryInterval();
            try {undefined
                LOGGER.info("Wait for {}", nextInterval);
                Thread.sleep(nextInterval);
            } catch (final InterruptedException e) {undefined
                Thread.currentThread().interrupt();
                throw new InterruptedIOException();
            }
            retryNum++;
            // retry the request
            response = doRequest(chain, request);
        }
        return response;
    }
    private Response doRequest(Chain chain, Request request) {undefined
        Response response = null;
        try {undefined
            response = chain.proceed(request);
        } catch (Exception e) {undefined
        }
        return response;
    }
    /**
     * retry間隔時間
     */
    public long getRetryInterval() {undefined
        return this.retryInterval;
    }
    public static final class Builder {undefined
        private int  executionCount;
        private long retryInterval;
        public Builder() {undefined
            executionCount = 3;
            retryInterval = 1000;
        }
        public Builder executionCount(int executionCount) {undefined
            this.executionCount = executionCount;
            return this;
        }
        public Builder retryInterval(long retryInterval) {undefined
            this.retryInterval = retryInterval;
            return this;
        }
        public OkHttpRetryInterceptor build() {undefined
            return new OkHttpRetryInterceptor(this);
        }
    }
}

2.註入feignClient bean

import java.util.concurrent.TimeUnit;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.boot.autoconfigure.AutoConfigureBefore;
import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
import org.springframework.cloud.netflix.feign.FeignAutoConfiguration;
import org.springframework.cloud.netflix.feign.ribbon.CachingSpringLoadBalancerFactory;
import org.springframework.cloud.netflix.feign.ribbon.LoadBalancerFeignClient;
import org.springframework.cloud.netflix.ribbon.SpringClientFactory;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import feign.Client;
import feign.Feign;
import feign.ribbon.RibbonClient;
import okhttp3.ConnectionPool;
import okhttp3.OkHttpClient;
@Configuration
@ConditionalOnMissingBean({ OkHttpClient.class, Client.class })
@ConditionalOnClass(Feign.class)
@AutoConfigureBefore(FeignAutoConfiguration.class)
public class FeignClientConfig {undefined
    @Value("${feign.invoke.http.connectTimeoutMillis:3000}")
    private int connectTimeoutMillis;
    @Value("${feign.invoke.http.readTimeoutMillis:10000}")
    private int readTimeoutMillis;
    @Value("${feign.invoke.http.retryExecutionCount:3}")
    private int retryExecutionCount;
    @Value("${feign.invoke.http.retryInterval:1000}")
    private int retryInterval;
    public FeignClientConfig() {undefined
    }
    @Bean
    @ConditionalOnMissingBean({ OkHttpClient.class })
    public OkHttpClient okHttpClient() {undefined
        OkHttpRetryInterceptor okHttpRetryInterceptor = new OkHttpRetryInterceptor.Builder().executionCount(retryExecutionCount)
                                                                                            .retryInterval(retryInterval)
                                                                                            .build();
        return new OkHttpClient.Builder().retryOnConnectionFailure(true)
                                         .addInterceptor(okHttpRetryInterceptor)
                                         .connectionPool(new ConnectionPool())
                                         .connectTimeout(connectTimeoutMillis, TimeUnit.MILLISECONDS)
                                         .readTimeout(readTimeoutMillis, TimeUnit.MILLISECONDS)
                                         .build();
    }
    @Bean
    @ConditionalOnMissingBean({ Client.class })
    public Client feignClient(CachingSpringLoadBalancerFactory cachingFactory, SpringClientFactory clientFactory) {undefined
        if (cachingFactory == null) {undefined
            RibbonClient.Builder builder = RibbonClient.builder();
            builder.delegate(new feign.okhttp.OkHttpClient(this.okHttpClient()));
            return builder.build();
        } else {undefined
            return new LoadBalancerFeignClient(new feign.okhttp.OkHttpClient(this.okHttpClient()), cachingFactory,
                                               clientFactory);
        }
    }
}

3.配置pom引用

 <dependency>
 <groupId>io.github.openfeign</groupId>
 <artifactId>feign-ribbon</artifactId>
 <version>9.0.0</version>
 </dependency>

4.寫feignClient

@FeignClient(name = "xxxApi", url = "${xxx.url}")
public interface xxxClient {
     @RequestMapping(method = RequestMethod.POST)
     public String createLink(@RequestHeader(name = "accessKey", defaultValue = "xx") String accessKey,
         @RequestHeader(name = "accessSecret") String accessSecret, @RequestBody String linkConfig);
}

5.寫熔斷器

    @Autowired
    private xxxClient xxClient;
    @HystrixCommand(commandKey = "xxxLink", fallbackMethod = "xxxError", commandProperties = { @HystrixProperty(name = "requestCache.enabled", value = "true"),
                                                                                                                           @HystrixProperty(name = "execution.isolation.thread.timeoutInMilliseconds", value = "5000") })
    public String xxLink(String accessKey, String accessSecret, String linkConfig) {
        LOG.info("[xxLink]  LinkConfig is {}", linkConfig);
        String resp = xxxClient.createLink(accessKey, accessSecret, linkConfig);
        LOG.info("[xxxLink] response : {}", resp);
        return resp;
    }

以上為個人經驗，希望能給大傢一個參考，也希望大傢多多支持WalkonNet。

推薦閱讀：