SpringCloud 整合 Python - Flask
前言
该篇文章分享如何将Python Web服务融入到Spring Cloud微服务体系中，并调用其服务，Python Web框架用的是Flask
方案
Sidecar+ Flask，在这里，我们会使用Sidecar将Python接口注册到SpringCloud中，将Python接口当作Java接口进行调用（通过SpringCloud去调用Sidecar，然后通过Sidecar去转发我们的程序请求）
Sidecar是SpringCloud提供的一个可将第三方的rest接口集成到SpringCloud中的工具
Python服务
manage.py
import json
from flask import Flask, Response, request, make_response, jsonify
app = Flask(__name__)
@app.route("/health")
def health():
result = {'status': 'UP'}
return Response(json.dumps(result), mimetype='application/json')
@app.route("/getUser")
def getUser():
result = {'username': 'python', 'password': 'python'}
return Response(json.dumps(result), mimetype='application/json')
@app.errorhandler(404)
def not_found(error):
return make_response(jsonify({'error': 'Not found'}), 404)
if __name__ == "__main__":
app.run(host="0.0.0.0", port=3000)
大致说下上述代码，Python服务监听3000端口，health方法用于给Sidecar提供健康接口，用于实时向Sidecar提供自己的健康状态，getUser是Python向外界提供的服务
- 运行方式
python manage.py runserver
sidecar-server工程
- 添加依赖
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-eureka</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-netflix-sidecar</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
SidecarApplication.java
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.sidecar.EnableSidecar;
@EnableSidecar
@SpringBootApplication
public class SidecarApplication {
public static void main(String[] args) {
SpringApplication.run(SidecarApplication.class, args);
}
}
application.yml
spring:
profiles:
active: "dev"
application:
name: demo-sidecar
sidecar:
port: 3000
health-uri: http://localhost:${sidecar.port}/health
ribbon:
ConnectTimeout: 50000
ReadTimeout: 50000
hystrix:
command:
default:
execution:
isolation:
thread:
timeoutInMilliseconds: 10000
server:
port: 8326
eureka:
client:
healthcheck:
enabled: true
service-url:
defaultZone: http://${registry.host:localhost}:${registry.port:8761}/eureka/
registry:
host: localhost
port: 31091
大致说下上述代码，main方法要使用@EnableSidecar注解，sidecar port代表监听Python运行的端口，server port代表Sidecar运行的端口，spring application name代表Sidecar的服务名，sidecar health-uri是Python健康接口，指向python的健康服务
服务调用 - consumer-server工程
调用方式一 : RestTemplate
ConsumerApplication.java
import org.springframework.boot.SpringApplication;
import org.springframework.cloud.client.SpringCloudApplication;
import org.springframework.cloud.client.loadbalancer.LoadBalanced;
import org.springframework.context.annotation.Bean;
import org.springframework.web.client.RestTemplate;
@SpringCloudApplication
public class ConsumerApplication {
@Bean
@LoadBalanced
RestTemplate restTemplate() {
return new RestTemplate();
}
public static void main(String[] args) {
SpringApplication.run(ConsumerApplication.class, args);
}
}
application.yml
spring:
profiles:
active: "dev"
application:
name: consumer-server
server:
port: 8325
eureka:
client:
healthcheck:
enabled: true
service-url:
defaultZone: http://${registry.host:localhost}:${registry.port:8761}/eureka/
---
spring:
profiles: dev
registry:
host: localhost
port: 31091
RestTemplateController.java
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;
@RestController
public class RestTemplateController {
@Autowired
private RestTemplate restTemplate;
@RequestMapping("/java-user")
public String JavaUser() {
return "{'username': 'java', 'password': 'java'}" ;
}
@RequestMapping("/python-user")
public String PythonUser() {
return restTemplate.getForEntity("http://sidecar-server/getUser", String.class).getBody();
// return restTemplate.getForEntity("http://localhost:3000/getUser", String.class).getBody();
}
}
- 这里做下说明，
@LoadBalanced用于开启负载均衡，在这里有两种调用方式，使用和不使用@LoadBalanced - 使用
@LoadBalanced注解后，RestTemplate可以直接调用服务名
@Bean
@LoadBalanced
RestTemplate restTemplate() {
return new RestTemplate();
}
++++++++++++++++++++++++++++++
return restTemplate.getForEntity("http://sidecar-server/getUser", String.class).getBody();
- 不使用
@LoadBalanced注解，RestTemplate调用的就是固定的IP+PORT
@Bean
// @LoadBalanced
RestTemplate restTemplate() {
return new RestTemplate();
}
++++++++++++++++++++++++++++++
return restTemplate.getForEntity("http://localhost:3000/getUser", String.class).getBody();
- 服务的启动顺序：
Python服务，注册中心，sidecar-server工程，consumer-server工程 - 运行结果
调用方式二: Feign
SidecarController.java
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;
import com.coisini.consumer.client.SidecarAPIClient;
@RestController
public class SidecarController {
private SidecarAPIClient sidecarAPIClient;
@Autowired
public SidecarController(SidecarAPIClient sidecarAPIClient) {
this.sidecarAPIClient = sidecarAPIClient;
}
@GetMapping("/getUser")
public Object getUser() {
return this.sidecarAPIClient.getUser();
}
}
SidecarAPIClient.java
import com.coisini.consumer.config.FeignConfigure;
import org.springframework.cloud.netflix.feign.FeignClient;
import org.springframework.web.bind.annotation.GetMapping;
@FeignClient(name="sidecar-server", configuration = FeignConfigure.class)
public interface SidecarAPIClient {
@GetMapping("/getUser")
Object getUser();
}
FeignConfigure.java
import feign.Logger;
import feign.codec.Encoder;
import feign.form.spring.SpringFormEncoder;
import org.springframework.beans.factory.ObjectFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.autoconfigure.web.HttpMessageConverters;
import org.springframework.cloud.netflix.feign.EnableFeignClients;
import org.springframework.cloud.netflix.feign.support.SpringEncoder;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
@Configuration
@EnableFeignClients(basePackages = "com.coisini")
public class FeignConfigure {
@Bean
Logger.Level feignLoggerLevel() {
return Logger.Level.FULL;
}
@Autowired
private ObjectFactory<HttpMessageConverters> messageConverters;
@Bean
public Encoder feignFormEncoder() {
return new SpringFormEncoder(new SpringEncoder(messageConverters));
}
}
- 服务的启动顺序：
Python服务，注册中心，sidecar-server工程，consumer-server工程 - 调用结果
至此，已完成微服务调用Python Web服务
Sidecar总结
Sidecar是一个用于监听非JVM应用程序(可以是Python或者Node或者Php等等)的一个工具，通过Sidecar可以实现Java和第三方应用程序的双向交互- 第三方应用程序必须要实现一个接口，实时向
Sidecar报告自己的状态，告诉Sidecar自己还在运行着。 Sidecar应用程序必须和第三方应用程序运行在同一台电脑上，也就是说他们之间是localhost，不能是IP访问
Demo下载
GitHub：SpringCloud 使用Sidecar整合Python Flask
Gitee：SpringCloud 使用Sidecar整合Python Flask
参考博客
SpringCloud 整合Python 感谢大佬
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