前言
在前面我们搭建起来了eureka,和配置中心，基于这两者我们就能愉快的写业务代码了。这章节我们看下怎么业务服务和业务服务直接如何完成调用。
这里我们需要创建两个项目分别叫demo1-service,demo2-service。demo1-service将会调用demo2提供的服务完成一个hello world。
一个架构图如下：
依赖
当前最新的spring boot版本为2.1.7 我们将他作为我们的parent。主要是方便三方jar的版本管理和maven插件的使用。
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<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.1.7.RELEASE</version>
</parent>
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加入spring cloud的pom依赖，方便spring cloud 提供的相关jar的版本管理。这里需要将此依赖放入dependencyManagement中
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<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-dependencies</artifactId>
<version>${spring-cloud.version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>
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需要服务发现所以导入eureka。不爱用jersey，直接排除掉
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<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
<exclusions>
<exclusion>
<groupId>com.sun.jersey</groupId>
<artifactId>jersey-client</artifactId>
</exclusion>
<exclusion>
<groupId>com.sun.jersey</groupId>
<artifactId>jersey-core</artifactId>
</exclusion>
<exclusion>
<groupId>com.sun.jersey.contribs</groupId>
<artifactId>jersey-apache-client4</artifactId>
</exclusion>
</exclusions>
</dependency>
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还需要ClientLB，加入ribbon。同样排除掉jersey
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<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-ribbon</artifactId>
<exclusions>
<exclusion>
<artifactId>jersey-client</artifactId>
<groupId>com.sun.jersey</groupId>
</exclusion>
<exclusion>
<artifactId>jersey-apache-client4</artifactId>
<groupId>com.sun.jersey.contribs</groupId>
</exclusion>
</exclusions>
</dependency>
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需要方便服务调用，加入openfeign依赖。
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<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-openfeign</artifactId>
</dependency>
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加入服务追踪zipkin，sleuth。
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<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-sleuth</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-zipkin</artifactId>
</dependency>
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POM
完整pom如下
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<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.1.7.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>io.qingmu</groupId>
<artifactId>demo1-service</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>demo1-service</name>
<properties>
<java.version>1.8</java.version>
<spring-cloud.version>Greenwich.SR2</spring-cloud.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
<exclusions>
<exclusion>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-tomcat</artifactId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-undertow</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-config</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
<exclusions>
<exclusion>
<groupId>com.sun.jersey</groupId>
<artifactId>jersey-client</artifactId>
</exclusion>
<exclusion>
<groupId>com.sun.jersey</groupId>
<artifactId>jersey-core</artifactId>
</exclusion>
<exclusion>
<groupId>com.sun.jersey.contribs</groupId>
<artifactId>jersey-apache-client4</artifactId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-ribbon</artifactId>
<exclusions>
<exclusion>
<artifactId>jersey-client</artifactId>
<groupId>com.sun.jersey</groupId>
</exclusion>
<exclusion>
<artifactId>jersey-apache-client4</artifactId>
<groupId>com.sun.jersey.contribs</groupId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-openfeign</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-sleuth</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-zipkin</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
</dependencies>
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-dependencies</artifactId>
<version>${spring-cloud.version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
<plugin>
<groupId>com.spotify</groupId>
<artifactId>docker-maven-plugin</artifactId>
<configuration>
<imageName>
freemanliu/eureka:v1.0.0
</imageName>
<registryUrl></registryUrl>
<workdir>/work</workdir>
<rm>true</rm>
<env>
<TZ>Asia/Shanghai</TZ>
<JAVA_OPTS>
-XX:+UnlockExperimentalVMOptions \
-XX:+UseCGroupMemoryLimitForHeap \
-XX:MaxRAMFraction=2 \
-XX:CICompilerCount=8 \
-XX:ActiveProcessorCount=8 \
-XX:+UseG1GC \
-XX:+AggressiveOpts \
-XX:+UseFastAccessorMethods \
-XX:+UseStringDeduplication \
-XX:+UseCompressedOops \
-XX:+OptimizeStringConcat
</JAVA_OPTS>
</env>
<baseImage>freemanliu/openjre:8.212</baseImage>
<cmd>
/sbin/tini java ${JAVA_OPTS} -jar ${project.build.finalName}.jar
</cmd>
<!--是否推送image-->
<pushImage>true</pushImage>
<resources>
<resource>
<directory>${project.build.directory}</directory>
<include>${project.build.finalName}.jar</include>
</resource>
</resources>
<serverId>docker-hub</serverId>
</configuration>
<executions>
<execution>
<phase>package</phase>
<goals>
<goal>build</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
</project>
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bootstrap.yml
这里配置一下eureka服务的地址，config-service会自动服务发现，不需要配置地址。
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spring:
cloud:
config:
label: master
failFast: true
discovery:
enabled: true
serviceId: config-service
eureka:
client:
serviceUrl:
defaultZone: ${EUREKA_SERVER:http://172.224.4.7:8761/eureka/}
instance:
# 使用ip注册。
prefer-ip-address: true
lease-renewal-interval-in-seconds: 10
lease-expiration-duration-in-seconds: 20
instance-id: ${spring.application.name}:${server.port}@${random.long(1000000,9999999)}
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application.yml
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server:
undertow:
worker-threads: 50
io-threads: 2
# demo1 port 8100. demo2 8101
port: 8100
compression:
enabled: true
mime-types: application/json,application/javascript,text/plain,application/x-javascript,text/css,application/xml
min-response-size: 4096
spring:
sleuth:
web:
client:
enabled: true
sampler:
# 配置采集率1.0表示100%，0.1表示10%
probability: ${SAMPLER_PROBABILITY:1.0}
application:
# demo1-service,demo2-service
name: demo1-service
http:
encoding:
charset: UTF-8
enabled: true
force: true
zipkin:
# 配置zipkin服务地址
base-url: ${ZIPKIN:http://10.96.0.13:9411/}
logging:
logPath: /var/log/${spring.application.name}
level:
com.netflix.discovery.shared.resolver.aws: ERROR
management:
endpoints:
web:
exposure:
include: "*"
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在config git上添加配置文件
我们需要在config的git仓库添加如下两个配置文件。方便我们从config-service获取到配置信息。
- demo1-service-default.properties
demo1Value=hello
- demo1-service-default.properties
demo2Value=world
Demo1-service
Demo1Resource
这里我们先编写demo1的资源API,这是一个十分简单的接口，当启动时，config-client活从远程的config-service获取到配置demo1Value的值，并注入进来，在访问/hello时，我们将返回给浏览器"hello"
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package io.qingmu.demo1;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;
@RestController
public class Demo1Resource {
@Value("${demo1Value}")
private String demo1Value;
@GetMapping("hello")
public String hello() {
return demo1Value;
}
}
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编写启动类Demo1ServiceApplication.
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package io.qingmu.demo1;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
import org.springframework.cloud.openfeign.EnableFeignClients;
@SpringBootApplication
@EnableDiscoveryClient
public class Demo1ServiceApplication {
public static void main(String[] args) {
SpringApplication.run(Demo1ServiceApplication.class, args);
}
}
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然后我们启动demo1-service。使用curl访问我们业务接口，会看到我们的
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$ curl http://localhost:8100/hello
hello
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Demo2-service
demo2的resource和demo1相差不多，这里不多说。
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package io.qingmu.demo2service;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;
@RestController
public class Demo2Resource {
@Value("${demo2Value}")
private String demo2Value;
@GetMapping("world")
public String hello() {
return demo2Value;
}
}
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编写启动类
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package io.qingmu.demo2service;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;
@SpringBootApplication
@EnableDiscoveryClient
public class Demo2ServiceApplication {
public static void main(String[] args) {
SpringApplication.run(Demo2ServiceApplication.class, args);
}
}
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启动成功后。我们使用curl访问demo2的服务
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$ curl http://localhost:8101/world
world
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这样我们就完成了demo1-service和demo2-service的基本编写。接下来我们来看下demo1需要调demo2应该怎么处理。
Feign Client 服务调服务。
首先我们在demo1中编写一个demo2的接口，并给接口加上@FeignClient注解，表示这是一个内部服务，注解的括号中我们填入服务名即可。
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package io.qingmu.demo1;
import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.web.bind.annotation.GetMapping;
@FeignClient("demo2-service")
public interface Demo2Client {
@GetMapping("/world")
String world();
}
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然后我们在Demo1Resource中注入该client。并改写hello方法。
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@RestController
public class Demo1Resource {
@Autowired
private Demo2Client demo2Client;
@Value("${demo1Value}")
private String demo1Value;
@GetMapping("hello")
public String hello() {
return demo1Value + " " + demo2Client.world();
}
}
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由于我们注入了feignclient，我们需要声明式的启用Feign组件，在启动类上添加注解@EnableFeignClients。
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@SpringBootApplication
@EnableDiscoveryClient
@EnableFeignClients
public class Demo1ServiceApplication {
public static void main(String[] args) {
SpringApplication.run(Demo1ServiceApplication.class, args);
}
}
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然后我们再次启动Demo1Service。
部分启动日志如下：
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2019-08-23 15:46:57.135 INFO [demo1-service,,,] 3710 --- [ main] org.xnio : XNIO version 3.3.8.Final
2019-08-23 15:46:57.148 INFO [demo1-service,,,] 3710 --- [ main] org.xnio.nio : XNIO NIO Implementation Version 3.3.8.Final
2019-08-23 15:46:57.151 INFO [demo1-service,,,] 3710 --- [nfoReplicator-0] com.netflix.discovery.DiscoveryClient : DiscoveryClient_DEMO1-SERVICE/demo1-service:8100@6670754 - registration status: 204
2019-08-23 15:46:57.230 INFO [demo1-service,,,] 3710 --- [ main] o.s.b.w.e.u.UndertowServletWebServer : Undertow started on port(s) 8100 (http) with context path ''
2019-08-23 15:46:57.230 INFO [demo1-service,,,] 3710 --- [ main] .s.c.n.e.s.EurekaAutoServiceRegistration : Updating port to 8100
2019-08-23 15:46:57.233 INFO [demo1-service,,,] 3710 --- [ main] io.qingmu.demo1.Demo1ServiceApplication : Started Demo1ServiceApplication in 5.057 seconds (JVM running for 5.77)
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再次访问demo1
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$ curl http://localhost:8100/hello
hello world
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Feign Get 传递对象
在使用feignclient时，默认是不允许http get 方法传递对象参数的，只能传递基本类型，但是我们实际业务中是需要get并传递对象进行业务功能的，比如说QueryModel查询对象。我们先来试验下，能不能传递。
首先我们定义一个模型就叫DemoQueryModel
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package io.qingmu.demo1;
import lombok.*;
@Setter
@Getter
@AllArgsConstructor
@NoArgsConstructor
@Builder
public class DemoQueryModel {
private String nameEQ;
}
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并在demo2-service中添加新的资源api,world2，这个方法将接受一个Query模型，并新构建一个返回出去。
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@GetMapping("world2")
public DemoQueryModel hello2(DemoQueryModel demo) {
return DemoQueryModel.builder().nameEQ(demo.getNameEQ()).build();
}
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写好了demo2-service之后我们接下来改造demo1-service。
我们将这个资源clent添加到Demo2Client中。
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@GetMapping("world2")
DemoQueryModel hello2(DemoQueryModel demo);
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在Demo1Resource，也新增一个资源叫hello2
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@GetMapping("hello2")
public DemoQueryModel hello2() {
return demo2Client.hello2(DemoQueryModel.builder().nameEQ("world").build());
}
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我们期待demo1，demo2，然后返回demo1提供的hello2资源。
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freemandeMacBook-Pro:demo1-service freeman$ curl -i http://localhost:8100/hello2
HTTP/1.1 500 Internal Server Error
Connection: keep-alive
Transfer-Encoding: chunked
Content-Type: application/json;charset=UTF-8
Date: Tue, 27 Aug 2019 04:36:17 GMT
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可以看到如下的结果，Feign抛出了405，MethodNotAllowed异常，感觉很奇怪。
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{
"timestamp":"2019-08-26T20:36:17.638+0000"
,"status":500
,"error":"Internal Server Error","message":"Request processing failed; nested exception is feign.FeignException$MethodNotAllowed: status 405 reading Demo2Client#hello2(DemoQueryModel)"
,"path":"/hello2"
}
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我们在看demo2这边的。控制台日志中记录了一条很奇怪的异常。它居然说Request method 'POST' not supported，可是我们明明发的是Get请求呀。
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1584 --- [ XNIO-1 task-3] .w.s.m.s.DefaultHandlerExceptionResolver : Resolved [org.springframework.web.HttpRequestMethodNotSupportedException: Request method 'POST' not supported]
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Feign Get请求自动变成了POST？
一路火花带闪电，debug下来，走到了sun.net.www.protocol.http.HttpURLConnection类中。
你问我为啥为啥会走到这个类，聊这个之前我们先看下feign实现桥接了几种后端httpclient具体实现。由于他们都是开源项目，我们可以直接通过代码直接看。
首先我们打开FeignAutoConfiguration这个类，这是配置feign的核心类。通过这个类我们可以知道，feign桥接了ApacheHttpClient，OkHttp。
这里我们没有导入ApacheHttpClient的maven依赖，所以这里不会被激活。
在看OkHttp，同样的道理，我们也没有导入OkHttp的maven依赖，这里依然不会被激活。
如果你也跟着我去看了这个类。你会发现这里都走完了，没有看到其他的实现啊。邪门了！！ 我们的http调用到底是咋个发起的呢？！！
怀着心有不甘，我点进了feign.Client中，发现了一片新天地，没错这里看到了我们想看到的。HttpURLConnection。
但是问题由来了，他是在哪里激活的呢？经过一番找寻。我找到了DefaultFeignLoadBalancedConfiguration，给他打上断，走你~~。果然走到这里来，当发现ApacheHttpClient和OkHttp都不能使用时，feign留了后手，直接用jdk自带的HttpURLConnection发起请求。
那这又和我们的疑问Get请求变成Post有啥关系呢？看到下面的截取自HttpURLConnection的代码就清楚了。这里居然把我们的GET请求换成了POST。我没太想明白为啥要这样做？历史原因？？
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private synchronized OutputStream getOutputStream0() throws IOException {
// ...
if (!this.doOutput) {
throw new ProtocolException("cannot write to a URLConnection if doOutput=false - call setDoOutput(true)");
} else {
if (this.method.equals("GET")) {
this.method = "POST";
}
// ...
}
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激活OKHTTP
好那么找到问题根源了，是后端实现的锅，我可更换一下后端实现换成OkHttp。
在maven中加入一下依赖，分别是okttp，feign-okhttp的桥接（即提供类feign.okhttp.OkHttpClient）实现。
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<dependency>
<groupId>com.squareup.okhttp3</groupId>
<artifactId>okhttp</artifactId>
<version>4.1.0</version>
</dependency>
<dependency>
<groupId>io.github.openfeign</groupId>
<artifactId>feign-okhttp</artifactId>
<version>10.3.0</version>
</dependency>
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紧接着需要在application中配置激活okhttp作为feign的后端实现。
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feign:
okhttp:
enabled: true
httpclient:
enabled: false
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此时我们在发起请求访问资源
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freemandeMacBook-Pro:demo1-service freeman$ curl -i http://localhost:8100/hello2
HTTP/1.1 500 Internal Server Error
Connection: keep-alive
Transfer-Encoding: chunked
Content-Type: application/json;charset=UTF-8
Date: Tue, 27 Aug 2019 08:07:40 GMT
{"timestamp":"2019-08-27T08:07:40.639+0000","status":500,"error":"Internal Server Error","message":"Request processing failed; nested exception is java.lang.RuntimeException: com.netflix.client.ClientException: Number of retries on next server exceeded max 1 retries, while making a call for: 192.168.0.66:8101","path":"/hello2"}
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现在访问抛出的异常错误是 Number of retries on next server exceeded max 1 retries, while making a call for: 192.168.0.66:810
这个从字面意思看上去就是异常了在重试，最好还是失败了。我们可以先禁用ribbon的重试。配置如下：
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ribbon:
okhttp:
enabled: true
MaxAutoRetries: 0
MaxAutoRetriesNextServer: 0
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禁用之后我们在发起，
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freemandeMacBook-Pro:demo1-service freeman$ curl -i http://localhost:8100/hello2
HTTP/1.1 500 Internal Server Error
Connection: keep-alive
Transfer-Encoding: chunked
Content-Type: application/json;charset=UTF-8
Date: Tue, 27 Aug 2019 08:12:09 GMT
{"timestamp":"2019-08-27T08:12:09.936+0000","status":500,"error":"Internal Server Error","message":"Request processing failed; nested exception is java.lang.RuntimeException: com.netflix.client.ClientException","path":"/hello2"}
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这次我们从返回的json中无法看到有用信息了，直接看控制台日志信息。这次换了个后端，虽然还是抛出异常，但是已经没有把我们的GET请求变成POST了。看异常很明显的意思是就是把我们的DemoQueryModel当成body了，然而get方法不允许传递body。这个难搞了。
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......
Caused by: java.lang.IllegalArgumentException: method GET must not have a request body.
at okhttp3.Request$Builder.method(Request.kt:258) ~[okhttp-4.1.0.jar:na]
at feign.okhttp.OkHttpClient.toOkHttpRequest(OkHttpClient.java:88) ~[feign-okhttp-10.3.0.jar:na]
at feign.okhttp.OkHttpClient.execute(OkHttpClient.java:166) ~[feign-okhttp-10.3.0.jar:na]
......
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@SpringQueryMap
在spring cloud 2.1.x 以上的版本，提供了一个新的注解@SpringQueryMap，使用这个注解呢，我们就可以传递了。接着我们把代码修改一下，在参数前添加一个注解。
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@GetMapping("world2")
DemoQueryModel hello2(@SpringQueryMap DemoQueryModel demo);
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再次请求，可以发现我们成功了。
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freemandeMacBook-Pro:demo1-service freeman$ curl -i http://localhost:8100/hello2
HTTP/1.1 200 OK
Connection: keep-alive
Transfer-Encoding: chunked
Content-Type: application/json;charset=UTF-8
Date: Tue, 27 Aug 2019 08:47:54 GMT
{"nameEQ":"world"}
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为啥加了一个注解就行了呢？为什么？？其实也很简单，既然不支持body传递，那么我们只需要些个拦截器，将body解析为url传参即可。
我们接下来简单的跟一下源码。
首先是注解处理器QueryMapParameterProcessor，一下代码截取自该类，这个注解处理器会在容器启动的时候对带有@SpringQueryMap参数注解的方法进行处理。
可以看到metadata.queryMapIndex() == null这句判断表示它只会处理参数中第一个@SpringQueryMap注解，其余的不会进行处理。紧接着把带有注解的参数的索引下标存了起来。
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@Override
public class QueryMapParameterProcessor implements AnnotatedParameterProcessor {
private static final Class<SpringQueryMap> ANNOTATION = SpringQueryMap.class;
@Override
public Class<? extends Annotation> getAnnotationType() {
return ANNOTATION;
}
@Override
public boolean processArgument(AnnotatedParameterContext context,
Annotation annotation, Method method) {
int paramIndex = context.getParameterIndex();
MethodMetadata metadata = context.getMethodMetadata();
if (metadata.queryMapIndex() == null) {
metadata.queryMapIndex(paramIndex);
metadata.queryMapEncoded(SpringQueryMap.class.cast(annotation).encoded());
}
return true;
}
}
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看完了解析部分，在看些具体使用的地方ReflectiveFeign，在这个类中有个方法是create,在225的位置，就用上了我们注解处理器设置好的元信息。
下面代码十分好懂：
- 首先是判断是否需要处理querymap。
- 然后通过下标获取到需要特殊处理的对象。
- 将对象转换外map
- 拼接追加map到url中。
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public RequestTemplate create(Object[] argv) {
...
if (metadata.queryMapIndex() != null) {
// add query map parameters after initial resolve so that they take
// precedence over any predefined values
Object value = argv[metadata.queryMapIndex()];
//将对象转换为map
Map<String, Object> queryMap = toQueryMap(value);
//拼接解析完成的对象为URL参数
template = addQueryMapQueryParameters(queryMap, template);
}
...
}
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我们通过一个小实验来看下，我们现在deme2-service中打一个断点。然后不放行，等到几秒之后，查看demo1-service抛出的异常信息。timeout executing GET http://demo2-service/world2?nameEQ=world 可以看到我们的模型被转换成了K=V参数。
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freemandeMacBook-Pro:demo1-service freeman$ curl -i http://localhost:8100/hello2
HTTP/1.1 500 Internal Server Error
Connection: keep-alive
Transfer-Encoding: chunked
Content-Type: application/json;charset=UTF-8
Date: Tue, 27 Aug 2019 08:45:05 GMT
{"timestamp":"2019-08-27T08:45:05.800+0000","status":500,"error":"Internal Server Error","message":"Request processing failed; nested exception is feign.RetryableException: timeout executing GET http://demo2-service/world2?nameEQ=world","path":"/hello2"}
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激活ApacheHttpClient
当然如果你更喜欢ApacheHttpClient，你就需要加入如下配置了
maven依赖，即提供feign.httpclient.ApacheHttpClient
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<dependency>
<groupId>io.github.openfeign</groupId>
<artifactId>feign-httpclient</artifactId>
<version>10.3.0</version>
</dependency>
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yaml文件
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feign:
okhttp:
enabled: false
httpclient:
enabled: true
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如果使用ApacheHttpClient的话不会抛出像OkHttp那样的错误，当然也不能正常处理，也是需要加上@SpringQueryMap注解，才能正常工作。
部署到kubernetes
在demo1-service，demo2-service分别执行打包命令
部署demo2
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apiVersion: v1
kind: Service
metadata:
name: demo2-service
namespace: default
labels:
app: demo2-service
spec:
ports:
- port: 8101
name: tcp
selector:
app: demo2-service
---
apiVersion: apps/v1
kind: Deployment
metadata:
name: demo2-service
namespace: default
spec:
revisionHistoryLimit: 10
strategy:
type: RollingUpdate
rollingUpdate:
maxUnavailable: 25%
maxSurge: 25%
replicas: 1
selector:
matchLabels:
app: demo2-service
template:
metadata:
labels:
app: demo2-service
spec:
affinity:
podAntiAffinity:
preferredDuringSchedulingIgnoredDuringExecution:
- podAffinityTerm:
topologyKey: kubernetes.io/hostname
labelSelector:
matchExpressions:
- key: app
operator: In
values:
- demo2-service
weight: 1
containers:
- name: demo2-service
image: freemanliu/demo2-service:v1.0.0
imagePullPolicy: Always
lifecycle:
preStop:
httpGet:
port: 8101
path: /spring/shutdown
livenessProbe:
httpGet:
path: /actuator/health
port: 8101
periodSeconds: 5
timeoutSeconds: 10
successThreshold: 1
failureThreshold: 5
readinessProbe:
httpGet:
path: /actuator/health
port: 8101
periodSeconds: 5
timeoutSeconds: 10
successThreshold: 1
failureThreshold: 5
resources:
requests:
memory: 1Gi
limits:
memory: 1Gi
ports:
- containerPort: 8101
env:
- name: EUREKA_SERVER
value: "http://eureka-0.eureka:8761/eureka/,http://eureka-1.eureka:8761/eureka/,http://eureka-2.eureka:8761/eureka/"
- name: SAMPLER_PROBABILITY
value: "1.0"
- name: ZIPKIN
value: "http://10.96.0.13:9411/"
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部署
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kubectl apply -f demo2-service.yaml
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部署demo1
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---
apiVersion: v1
kind: Service
metadata:
name: demo1-service
namespace: default
labels:
app: demo1-service
spec:
ports:
- port: 8100
name: tcp
selector:
app: demo1-service
---
apiVersion: apps/v1
kind: Deployment
metadata:
name: demo1-service
namespace: default
spec:
revisionHistoryLimit: 10
strategy:
type: RollingUpdate
rollingUpdate:
maxUnavailable: 25%
maxSurge: 25%
replicas: 1
selector:
matchLabels:
app: demo1-service
template:
metadata:
labels:
app: demo1-service
spec:
affinity:
podAntiAffinity:
preferredDuringSchedulingIgnoredDuringExecution:
- podAffinityTerm:
topologyKey: kubernetes.io/hostname
labelSelector:
matchExpressions:
- key: app
operator: In
values:
- demo1-service
weight: 1
containers:
- name: demo1-service
image: freemanliu/demo1-service:v1.0.0
imagePullPolicy: Always
lifecycle:
preStop:
httpGet:
port: 8100
path: /spring/shutdown
livenessProbe:
httpGet:
path: /actuator/health
port: 8100
periodSeconds: 5
timeoutSeconds: 10
successThreshold: 1
failureThreshold: 5
readinessProbe:
httpGet:
path: /actuator/health
port: 8100
periodSeconds: 5
timeoutSeconds: 10
successThreshold: 1
failureThreshold: 5
resources:
requests:
memory: 1Gi
limits:
memory: 1Gi
ports:
- containerPort: 8100
env:
- name: EUREKA_SERVER
value: "http://eureka-0.eureka:8761/eureka/,http://eureka-1.eureka:8761/eureka/,http://eureka-2.eureka:8761/eureka/"
- name: SAMPLER_PROBABILITY
value: "1.0"
- name: ZIPKIN
value: "http://10.96.0.13:9411/"
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部署
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kubectl apply -f demo1-service.yaml
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查看状态
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freemandeMacBook-Pro$ kubectl get pods -owide | grep demo
demo1-service-7fbd969f45-fzs9q 1/1 Running 0 3m52s 172.224.5.53 node3 <none> <none>
demo2-service-fcf59b8c7-z5znb 1/1 Running 0 14m 172.224.7.39 node6 <none> <none>
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使用浏览器访问demo1-service，可以看到成功了。
Github