使用feign對接微信支付v3

feign不只能夠用來進行服務間的通訊，還能夠用來對接第三方api接口。

先來個示例

就像寫controller同樣向微信發送請求。幫你把簽名之類的工做全給作了。

/** * 微信app支付feign * * @author yanghx */
@Component
@FeignClient(url = "https://api.mch.weixin.qq.com", name = "wechatAppPayFeign", configuration = WechatAppPayFeignConfig.class)
public interface WechatAppPayFeign {


    /** * 發起預支付 * * @param params 預支付參數 * @return 預支付返回信息 */
    @PostMapping("/v3/pay/transactions/app")
    WechatAppPrepayResult prepay(WechatAppPrepayParams params);


    /** * 微信支付訂單號查詢.根據微信的訂單id * * @param transactionId 微信支付訂單號 * @param mchId 商戶id * @return o */
    @GetMapping("/v3/pay/transactions/id/{transaction_id}")
    WechatAppQueryResult queryForWechatOrderId(@PathVariable(name = "transaction_id") String transactionId, @RequestParam(name = "mchid") String mchId);


    /** * 微信支付訂單號查詢.根據商戶的訂單號 * * @param outTradeNo 商戶訂單號 * @param mchId 商戶id * @return o */
    @GetMapping("/v3/pay/transactions/out-trade-no/{out_trade_no}")
    WechatAppQueryResult queryForOutTradeNo(@PathVariable(name = "out_trade_no") String outTradeNo, @RequestParam(name = "mchid") String mchId);


    /** * 取消訂單 * * @param outTradeNo 商戶訂單號 * @param params 參數 * @return o */
    @PostMapping("/v3/pay/transactions/out-trade-no/{out_trade_no}/close")
    feign.Response close(@PathVariable(name = "out_trade_no") String outTradeNo, @RequestBody WechatAppPayCloseParams params);


    @GetMapping("/v3/certificates")
    @Headers({ "Accept: application/json" })
    public Object certificates();
}
複製代碼

用到的技術點

wechatpay-apache-httpclient

微信支付Api v3 提供的http client 擴展，實現了請求籤名的生成和應答簽名的驗證。

spring-cloud-starter-openfeign

<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-openfeign</artifactId>
    <version>2.2.3.RELEASE</version>
</dependency>
<dependency>
    <groupId>io.github.openfeign</groupId>
    <artifactId>feign-httpclient</artifactId>
    <version>10.1.0</version>
    <scope>compile</scope>
</dependency>
複製代碼

這裏用到了feign和feign-httpclient。

feign默認採用reastTemplate進行網路請求，可是也支持採用httpclient,OKhttp進行替換。這裏就是經過將wechatpay-apache-httpclient提供的httpclient實例注入到feign中來進行整合的

feign和wechatpay-apache-httpclient的整合

首先看下feign的代碼(實際上是spring-cloud-starter-openfeign提供的整合代碼)

/* * Copyright 2013-2020 the original author or authors. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * https://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */

package org.springframework.cloud.openfeign;

import java.util.ArrayList;
import java.util.List;
import java.util.Timer;
import java.util.TimerTask;
import java.util.concurrent.TimeUnit;

import javax.annotation.PreDestroy;

import feign.Client;
import feign.Feign;
import feign.httpclient.ApacheHttpClient;
import feign.okhttp.OkHttpClient;
import okhttp3.ConnectionPool;
import org.apache.http.client.HttpClient;
import org.apache.http.client.config.RequestConfig;
import org.apache.http.config.RegistryBuilder;
import org.apache.http.conn.HttpClientConnectionManager;
import org.apache.http.impl.client.CloseableHttpClient;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingClass;
import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
import org.springframework.boot.context.properties.EnableConfigurationProperties;
import org.springframework.cloud.client.actuator.HasFeatures;
import org.springframework.cloud.commons.httpclient.ApacheHttpClientConnectionManagerFactory;
import org.springframework.cloud.commons.httpclient.ApacheHttpClientFactory;
import org.springframework.cloud.commons.httpclient.OkHttpClientConnectionPoolFactory;
import org.springframework.cloud.commons.httpclient.OkHttpClientFactory;
import org.springframework.cloud.openfeign.support.DefaultGzipDecoderConfiguration;
import org.springframework.cloud.openfeign.support.FeignHttpClientProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Import;

/** * @author Spencer Gibb * @author Julien Roy */
@Configuration(proxyBeanMethods = false)
@ConditionalOnClass(Feign.class)
@EnableConfigurationProperties({ FeignClientProperties.class, FeignHttpClientProperties.class })
@Import(DefaultGzipDecoderConfiguration.class)
public class FeignAutoConfiguration {

   @Autowired(required = false)
   private List<FeignClientSpecification> configurations = new ArrayList<>();

   @Bean
   public HasFeatures feignFeature() {
      return HasFeatures.namedFeature("Feign", Feign.class);
   }

   @Bean
   public FeignContext feignContext() {
      FeignContext context = new FeignContext();
      context.setConfigurations(this.configurations);
      return context;
   }

   @Configuration(proxyBeanMethods = false)
   @ConditionalOnClass(name = "feign.hystrix.HystrixFeign")
   protected static class HystrixFeignTargeterConfiguration {

      @Bean
      @ConditionalOnMissingBean
      public Targeter feignTargeter() {
         return new HystrixTargeter();
      }

   }

   @Configuration(proxyBeanMethods = false)
   @ConditionalOnMissingClass("feign.hystrix.HystrixFeign")
   protected static class DefaultFeignTargeterConfiguration {

      @Bean
      @ConditionalOnMissingBean
      public Targeter feignTargeter() {
         return new DefaultTargeter();
      }

   }

   // the following configuration is for alternate feign clients if
   // ribbon is not on the class path.
   // see corresponding configurations in FeignRibbonClientAutoConfiguration
   // for load balanced ribbon clients.
   @Configuration(proxyBeanMethods = false)
   @ConditionalOnClass(ApacheHttpClient.class)
   @ConditionalOnMissingClass("com.netflix.loadbalancer.ILoadBalancer")
   @ConditionalOnMissingBean(CloseableHttpClient.class)
   @ConditionalOnProperty(value = "feign.httpclient.enabled", matchIfMissing = true)
   protected static class HttpClientFeignConfiguration {

      private final Timer connectionManagerTimer = new Timer(
            "FeignApacheHttpClientConfiguration.connectionManagerTimer", true);

      @Autowired(required = false)
      private RegistryBuilder registryBuilder;

      private CloseableHttpClient httpClient;

      @Bean
      @ConditionalOnMissingBean(HttpClientConnectionManager.class)
      public HttpClientConnectionManager connectionManager( ApacheHttpClientConnectionManagerFactory connectionManagerFactory, FeignHttpClientProperties httpClientProperties) {
         final HttpClientConnectionManager connectionManager = connectionManagerFactory
               .newConnectionManager(httpClientProperties.isDisableSslValidation(),
                     httpClientProperties.getMaxConnections(),
                     httpClientProperties.getMaxConnectionsPerRoute(),
                     httpClientProperties.getTimeToLive(),
                     httpClientProperties.getTimeToLiveUnit(),
                     this.registryBuilder);
         this.connectionManagerTimer.schedule(new TimerTask() {
            @Override
            public void run() {
               connectionManager.closeExpiredConnections();
            }
         }, 30000, httpClientProperties.getConnectionTimerRepeat());
         return connectionManager;
      }

      @Bean
      public CloseableHttpClient httpClient(ApacheHttpClientFactory httpClientFactory, HttpClientConnectionManager httpClientConnectionManager, FeignHttpClientProperties httpClientProperties) {
         RequestConfig defaultRequestConfig = RequestConfig.custom()
               .setConnectTimeout(httpClientProperties.getConnectionTimeout())
               .setRedirectsEnabled(httpClientProperties.isFollowRedirects())
               .build();
         this.httpClient = httpClientFactory.createBuilder()
               .setConnectionManager(httpClientConnectionManager)
               .setDefaultRequestConfig(defaultRequestConfig).build();
         return this.httpClient;
      }

      @Bean
      @ConditionalOnMissingBean(Client.class)
      public Client feignClient(HttpClient httpClient) {
         return new ApacheHttpClient(httpClient);
      }

      @PreDestroy
      public void destroy() throws Exception {
         this.connectionManagerTimer.cancel();
         if (this.httpClient != null) {
            this.httpClient.close();
         }
      }

   }

   @Configuration(proxyBeanMethods = false)
   @ConditionalOnClass(OkHttpClient.class)
   @ConditionalOnMissingClass("com.netflix.loadbalancer.ILoadBalancer")
   @ConditionalOnMissingBean(okhttp3.OkHttpClient.class)
   @ConditionalOnProperty("feign.okhttp.enabled")
   protected static class OkHttpFeignConfiguration {

      private okhttp3.OkHttpClient okHttpClient;

      @Bean
      @ConditionalOnMissingBean(ConnectionPool.class)
      public ConnectionPool httpClientConnectionPool( FeignHttpClientProperties httpClientProperties, OkHttpClientConnectionPoolFactory connectionPoolFactory) {
         Integer maxTotalConnections = httpClientProperties.getMaxConnections();
         Long timeToLive = httpClientProperties.getTimeToLive();
         TimeUnit ttlUnit = httpClientProperties.getTimeToLiveUnit();
         return connectionPoolFactory.create(maxTotalConnections, timeToLive, ttlUnit);
      }

      @Bean
      public okhttp3.OkHttpClient client(OkHttpClientFactory httpClientFactory, ConnectionPool connectionPool, FeignHttpClientProperties httpClientProperties) {
         Boolean followRedirects = httpClientProperties.isFollowRedirects();
         Integer connectTimeout = httpClientProperties.getConnectionTimeout();
         Boolean disableSslValidation = httpClientProperties.isDisableSslValidation();
         this.okHttpClient = httpClientFactory.createBuilder(disableSslValidation)
               .connectTimeout(connectTimeout, TimeUnit.MILLISECONDS)
               .followRedirects(followRedirects).connectionPool(connectionPool)
               .build();
         return this.okHttpClient;
      }

      @PreDestroy
      public void destroy() {
         if (this.okHttpClient != null) {
            this.okHttpClient.dispatcher().executorService().shutdown();
            this.okHttpClient.connectionPool().evictAll();
         }
      }

      @Bean
      @ConditionalOnMissingBean(Client.class)
      public Client feignClient(okhttp3.OkHttpClient client) {
         return new OkHttpClient(client);
      }

   }

}
複製代碼

咱們要作的就是重寫httpClient和feignClient這兩個bean。 這樣項目啓動時就會以httpclient進行feign請求了。 而後咱們再根據微信wechatpay-apache-httpclient提供的文檔進行支付信息配置就能夠了。 這樣子再進行支付相關請求時，httpclient就會自動接口認證和簽名了。

package cn.yanghx.pay.feign;



/** * 微信app支付feign配置 * * @author yanghx */
public class WechatAppPayFeignConfig {

 
    @Resource
    private PayProperties payProperties;

    @Bean
    public CloseableHttpClient httpClient() {
        WechatAppPayProperties wechatAppPayProperties = payProperties.getWechat().getApp();

        if (wechatAppPayProperties.isEmpty()) {
            throw new WechatAppPayException("須要配置app支付相關配置");
        }

        String mchId = wechatAppPayProperties.getMchId();
        String mchSerialNo = wechatAppPayProperties.getMchSerialNo();
        String apiV3Key = wechatAppPayProperties.getApiV3Key();
        String privateKey = wechatAppPayProperties.getPrivateKey();
        PrivateKey merchantPrivateKey = PemUtil.loadPrivateKey(
                new ByteArrayInputStream(privateKey.getBytes(StandardCharsets.UTF_8)));
        //不須要傳入微信支付證書了
        AutoUpdateCertificatesVerifier verifier = new AutoUpdateCertificatesVerifier(
                new WechatPay2Credentials(mchId, new PrivateKeySigner(mchSerialNo, merchantPrivateKey)),
                apiV3Key.getBytes(StandardCharsets.UTF_8));
        //微信提供的簽名工具
        WechatPayHttpClientBuilder builder = WechatPayHttpClientBuilder.create()
                .withMerchant(mchId, mchSerialNo, merchantPrivateKey)
                .withValidator(new WechatPay2Validator(verifier));
// 經過WechatPayHttpClientBuilder構造的HttpClient，會自動的處理簽名和驗籤，並進行證書自動更新
        return builder.build();
    }

    /** * 這兩個bean的做用是。將feign的請求地址換成httpclient。 而後本身提供httpClient 。 並設置攔截器 * * @param httpClient client * @return client */
    @Bean
    public Client feignClient(HttpClient httpClient) {
        return new ApacheHttpClient(httpClient);
    }
}
}
複製代碼

結語

採用feign接入wechatpay-apache-httpclient實際上是一種比較麻煩的作法，須要處理幾個框架的兼容問題。 優勢就是用了feign以後，寫第三方接口方便了，再也不像之前是一堆字符串，而後簽名之類的代碼都是寫在一塊兒的，改起來也方便。

demo項目展現

說明：

• 這只是一個demo項目，是我從項目代碼中抽出來的。目前只實現了微信app支付相關接口，若是有其它支付要對接，須要本身寫(搞懂模式後，寫起來很快的)。
• 再有就是實際開發中，建議採用starter的形式引用。咱們項目也是封裝的starter，只是拿來作demo就把一些代碼複製出來了。
• 這種作法只是一個快速開發的方式。若是項目中用到支付很頻繁，建議採用一些成熟的支付庫。

源碼地址

gitee.com/yanghx_git/…

配置信息說明

pay:
  config:
    wechat:
      app:
        appId: xxx
        # 商戶id
        mchId: xxx
        # 商戶證書序列號
        mchSerialNo: xxxx
        # api密鑰
        apiV3Key: xxxx
        #回調地址
        notifyUrl: http://xxx/callback
        # 商戶私鑰。apiclient_key.pem中的文本
        privateKey: "-----BEGIN PRIVATE KEY-----   -----END PRIVATE KEY-----"
複製代碼