Springboot+freemaker+eureka+fegin实现多文件上传，完整demo

可能一般用fegin实现文件上传的不多，但这也算是一个文件上传方式吧，如果用到了，可以考虑借鉴一下，直接上代码好了

eureka

pom.xml

<?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>2.1.1.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.demo</groupId>
    <artifactId>fileeureka</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>fileeureka</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <java.version>1.8</java.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-server</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
            <exclusions>
                <exclusion>
                    <groupId>org.junit.vintage</groupId>
                    <artifactId>junit-vintage-engine</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
    </dependencies>
    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>Greenwich.SR1</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>
        </plugins>
    </build>

</project>

启动类

这个服务器中只有这一个类

package com.demo;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.server.EnableEurekaServer;

@SpringBootApplication
@EnableEurekaServer
public class FileEurekaApp {

    public static void main(String[] args) {
        SpringApplication.run(FileEurekaApp.class, args);
    }

}

配置

server.port=9999
spring.application.name=fileeureka

eureka.instance.hostname=127.0.0.1
eureka.instance.preferIpAddress=true
eureka.client.registerWithEureka=false
eureka.client.fetchRegistry=false
eureka.client.serviceUrl.defaultZone=http://${eureka.instance.hostname}:${server.port}/eureka/

文件服务端

pom.xml

<?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>2.1.1.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.demo</groupId>
    <artifactId>fileserver</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>fileserver</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <java.version>1.8</java.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-openfeign</artifactId>
        </dependency>
        <dependency>
            <groupId>io.github.openfeign</groupId>
            <artifactId>feign-httpclient</artifactId>
        </dependency>
        <dependency>
            <groupId>io.github.openfeign.form</groupId>
            <artifactId>feign-form</artifactId>
            <version>3.8.0</version>
        </dependency>
        <dependency>
            <groupId>io.github.openfeign.form</groupId>
            <artifactId>feign-form-spring</artifactId>
            <version>3.8.0</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/com.google.code.gson/gson -->
        <dependency>
            <groupId>com.google.code.gson</groupId>
            <artifactId>gson</artifactId>
            <version>2.8.5</version>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
            <exclusions>
                <exclusion>
                    <groupId>org.junit.vintage</groupId>
                    <artifactId>junit-vintage-engine</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
    </dependencies>
    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>Greenwich.SR1</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>

            <dependency>
                <groupId>io.projectreactor</groupId>
                <artifactId>reactor-bom</artifactId>
                <version>Dysprosium-SR25</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>
        </plugins>
    </build>

</project>

工具类

package com.demo.utils;

import com.google.gson.Gson;

public class GsonUtils<T> {

    private static final Gson gson = new Gson();


    public static <T> String object2Json(T t){
        return gson.toJson(t);
    }

    public  static <T> T jsonStr2Object(String json, Class<T> clazz){
        return gson.fromJson(json,clazz);
    }
}

启动类

package com.demo;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.client.discovery.EnableDiscoveryClient;

@SpringBootApplication
@EnableDiscoveryClient
public class FileServerApp {

    public static void main(String[] args) {
        SpringApplication.run(FileServerApp.class, args);
    }

}

文件接收处理类

package com.demo.rpc;

import com.demo.utils.GsonUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.MediaType;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import java.io.*;

@RestController
@RequestMapping("/rpc")
public class FileRpcService {
    private Logger logger = LoggerFactory.getLogger(FileRpcService.class);

    @Autowired
    private HttpServletRequest request;

    @RequestMapping(value = "uploadFile", method = RequestMethod.POST, consumes = MediaType.MULTIPART_FORM_DATA_VALUE, produces = {MediaType.APPLICATION_JSON_UTF8_VALUE})
    public String uploadFile(@RequestParam("file") MultipartFile[] files) {

        logger.info("file size: {}", files==null ?0:files.length);
        for(MultipartFile file: files){
            BufferedReader reader = null;
            try {
                reader = new BufferedReader(new InputStreamReader(file.getInputStream()));
                String line = null;
                StringBuilder sb = new StringBuilder();
                while((line = reader.readLine())!=null){
                    sb.append(line);
                    line = null;
                }

                logger.info("fileName: {}, fileContent: {}", file.getOriginalFilename(), sb.toString());
            } catch (IOException e) {
                throw new RuntimeException(e);
            }finally {
                if(reader!=null){
                    try {
                        reader.close();
                    } catch (IOException e) {
                        throw new RuntimeException(e);
                    }
                }
            }
        }

        try {
            // 用于测试，如果不知道接收用什么文件名，可以打印出来
            logger.info("********** parts: {}", GsonUtils.object2Json(request.getParts()));
        } catch (IOException e) {
            throw new RuntimeException(e);
        } catch (ServletException e) {
            throw new RuntimeException(e);
        }

        return "success";
    }
}

配置

server.port=8888
spring.application.name=fileserver

eureka.client.serviceUrl.defaultZone=http://127.0.0.1:9999/eureka/
eureka.instance.prefer-ip-address=true

文件上传客户端

pom.xml

<?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>2.1.1.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.demo</groupId>
    <artifactId>fileclient</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>fileclient</name>
    <description>Demo project for Spring Boot</description>

    <properties>
        <java.version>1.8</java.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </dependency>
        <dependency>
            <groupId>com.google.code.gson</groupId>
            <artifactId>gson</artifactId>
        </dependency>
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-lang3</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-freemarker</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-starter-openfeign</artifactId>
        </dependency>
        <dependency>
            <groupId>io.github.openfeign</groupId>
            <artifactId>feign-httpclient</artifactId>
        </dependency>
        <dependency>
            <groupId>io.github.openfeign.form</groupId>
            <artifactId>feign-form</artifactId>
            <version>3.8.0</version>
        </dependency>
        <dependency>
            <groupId>io.github.openfeign.form</groupId>
            <artifactId>feign-form-spring</artifactId>
            <version>3.8.0</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
            <exclusions>
                <exclusion>
                    <groupId>org.junit.vintage</groupId>
                    <artifactId>junit-vintage-engine</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
    </dependencies>
    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.springframework.cloud</groupId>
                <artifactId>spring-cloud-dependencies</artifactId>
                <version>Greenwich.SR1</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>
        </plugins>
    </build>

</project>

页面

src/mian/resources/templates/index.ftl

<!DOCTYPE html>
<html>
    <head>
        <title>Home page</title>
        <meta charset="UTF-8">
        <meta name="viewport" content="width=device-width, initial-scale=1.0">
    </head>

    <body>
        <form action="/upload" method = "post", enctype="multipart/form-data">
            <!-- <input type="input" name="title"/> <br/>-->
            <input type="file" name="file"/> <br/>
            <input type="file" name="file"/> <br/>
            <input type="submit" name="submit"/>
        </form>
    </body>

</html>

启动类

package com.demo;

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
@EnableFeignClients
@EnableDiscoveryClient
public class FileClientApp {

    public static void main(String[] args) {
        SpringApplication.run(FileClientApp.class, args);
    }

}

 

接收前端传递的文件控制器

package com.demo.freemaker.controller;

import com.demo.freemaker.feign.FileFeignClient;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.MediaType;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.multipart.MultipartFile;

@Controller
public class TController {
    @Autowired
    private FileFeignClient fileFeignClient;

    @RequestMapping("/")
    public String toIndex(){
        return "index";
    }

    @ResponseBody
    @RequestMapping(value = "/upload", method = RequestMethod.POST, consumes = MediaType.MULTIPART_FORM_DATA_VALUE, produces = {MediaType.APPLICATION_JSON_UTF8_VALUE})
    public void upload(@RequestParam("file") MultipartFile[] file){
        fileFeignClient.uploadFile(file);
    }
}

fegin文件上传接口

package com.demo.freemaker.feign;

import com.demo.freemaker.config.FeignMultiPartFileConfig;
import org.springframework.cloud.openfeign.FeignClient;
import org.springframework.http.MediaType;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestPart;
import org.springframework.web.multipart.MultipartFile;

@FeignClient(name="FILESERVER", contextId = "myFileFeign", configuration = FeignMultiPartFileConfig.class)
public interface FileFeignClient {

    @RequestMapping(value="/rpc/uploadFile", method = RequestMethod.POST, consumes = MediaType.MULTIPART_FORM_DATA_VALUE, produces = {MediaType.APPLICATION_JSON_UTF8_VALUE})
    String uploadFile(@RequestPart(value="files", required = false )MultipartFile[] files);
}

文件上传自定义配置

package com.demo.freemaker.config;

import feign.RequestTemplate;
import feign.codec.EncodeException;
import feign.codec.Encoder;
import feign.form.ContentType;
import feign.form.FormEncoder;
import feign.form.MultipartFormContentProcessor;
import feign.form.spring.SpringManyMultipartFilesWriter;
import feign.form.spring.SpringSingleMultipartFileWriter;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.ObjectFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.autoconfigure.http.HttpMessageConverters;
import org.springframework.cloud.openfeign.support.SpringEncoder;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.multipart.MultipartFile;

import java.lang.reflect.Type;
import java.util.*;

@Configuration
public class FeignMultiPartFileConfig {

    @Autowired
    private ObjectFactory<HttpMessageConverters> messageConverters;

    @Bean
    public Encoder feignFormEncoder() {
        return new CustomEncoder(new SpringEncoder(messageConverters));
    }

    class CustomEncoder extends FormEncoder {
        private Logger logger = LoggerFactory.getLogger(CustomEncoder.class);
        public CustomEncoder(Encoder encoder) {
            super(encoder);
            MultipartFormContentProcessor processor = (MultipartFormContentProcessor) getContentProcessor(ContentType.MULTIPART);
            processor.addFirstWriter(new SpringSingleMultipartFileWriter());
            processor.addFirstWriter(new SpringManyMultipartFilesWriter());
        }

        @Override
        public void encode(Object object, Type bodyType, RequestTemplate template) throws EncodeException {
            processMultipartFile(object, bodyType, template);
        }

        private void processMultipartFile(Object object, Type bodyType, RequestTemplate template) {
            if (bodyType != null && bodyType.equals(MultipartFile.class)) {
                MultipartFile file = (MultipartFile) object;
                Map<String, Object> stringObjectMap = Collections.singletonMap(file.getName(), object);
                super.encode(stringObjectMap, MAP_STRING_WILDCARD, template);
            } else if (bodyType != null && bodyType.equals(MultipartFile[].class)) {
                MultipartFile[] file = (MultipartFile[]) object;
                if (file != null) {
                    Map<String, Object> stringObjectMap = Collections.singletonMap(file.length == 0 ? "" : file[0].getName(), object);
                    // file[0].getName(): file, stringObjectMap: {file=[Lorg.springframework.web.multipart.MultipartFile;@750c26f5},
                    // 这里可能是导致服务端必须以file名称接收文件数组的原因
                    super.encode(stringObjectMap, MAP_STRING_WILDCARD, template);
                }
            } else {
                super.encode(object, bodyType, template);
            }

        }
    }
}

配置文件

server.port=8080
eureka.client.serviceUrl.defaultZone=http://127.0.0.1:9999/eureka/
eureka.instance.prefer-ip-address=true
## 非必须
spring.main.allow-bean-definition-overriding=true

运行结果

 

 到此，全部结束，但这里需要注意：

1、feign客户端上传的文件，使用requestparam定义的名称在文件接收服务端不一定有用（本例中，fegin客户端使用的files上传文件，文件服务端只能用file接收，不能用files，files接收不到文件），文件接收服务端接收的为文件的名称，从测试结果看，该名称与前端传递过来的name相同，如果不确定名称，可以通过打印request.getParts()中的内容来确定