• (仿牛客社区项目)Java开发笔记7.8:将文件上传至服务器


    将文件上传至服务器

    NowCoder_37_1

    1.导入依赖

    pom.xml导包。

    		<dependency>
    			<groupId>com.qiniugroupId>
    			<artifactId>qiniu-java-sdkartifactId>
    			<version>7.2.23version>
    		dependency>
    
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    2.修改配置文件

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    配置文件添加相关配置【非必要】,与创建及网站提供的信息一一对应。

    #标识用户身份
    qiniu.key.access=aaaaaaaaaaaaaa
    #上传具体内容为内容加密
    qiniu.key.secret=bbbbbbbbbbbbbb
    
    qiniu.bucket.share.name=gerrard-community-header
    qiniu.bucket.share.url=http://xxxxxxxx.xxxx.clouddn.com
    
    qiniu.bucket.header.name=gerrard-community-share
    quniu.bucket.header.url=http://xxxxxxxx.xxxx.clouddn.com
    
    
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    3.上传头像

    3.1controller层

    UserController中添加相关字段,废弃uploadHeader,getHeader方法,修改getSettingPage方法,添加updateHeaderUrl方法。

    package com.gerrard.community.controller;
    
    import com.gerrard.community.annotation.LoginRequired;
    import com.gerrard.community.entity.User;
    import com.gerrard.community.service.FollowerService;
    import com.gerrard.community.service.LikeService;
    import com.gerrard.community.service.UserService;
    import com.gerrard.community.util.CommunityConstant;
    import com.gerrard.community.util.CommunityUtil;
    import com.gerrard.community.util.HostHolder;
    import com.qiniu.util.Auth;
    import com.qiniu.util.StringMap;
    import org.apache.commons.lang3.StringUtils;
    import org.slf4j.Logger;
    import org.slf4j.LoggerFactory;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.beans.factory.annotation.Value;
    import org.springframework.stereotype.Controller;
    import org.springframework.ui.Model;
    import org.springframework.web.bind.annotation.PathVariable;
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.bind.annotation.RequestMethod;
    import org.springframework.web.bind.annotation.ResponseBody;
    import org.springframework.web.multipart.MultipartFile;
    
    import javax.servlet.http.HttpServletResponse;
    import java.io.*;
    import java.util.Map;
    
    @Controller
    @RequestMapping("/user")
    public class UserController implements CommunityConstant {
    
    
        private static final Logger logger= LoggerFactory.getLogger(UserController.class);
    
        @Value("${community.path.upload}")
        private String uploadPath;
    
        @Value("${community.path.domain}")
        private String domain;
    
        @Value("${server.servlet.context-path}")
        private String contextPath;
    
        @Autowired
        private UserService userService;
    
        @Autowired
        private LikeService likeService;
    
        @Autowired
        private FollowerService followerService;
    
        @Autowired
        private HostHolder hostHolder;
    
    
        @Value("${qiniu.key.access}")
        private String accessKey;
    
        @Value("${qiniu.key.secret}")
        private String secretKey;
    
        @Value("${qiniu.bucket.header.name}")
        private String headerBucketName;
    
        @Value("${quniu.bucket.header.url}")  //七牛云对外暴露的图片链接,不是上传的url
        private String headerBucketUrl;
    
        @LoginRequired
        @RequestMapping(path="/setting",method = RequestMethod.GET )
        public String getSettingPage(Model model){
            //上传文件名称
            String fileName=CommunityUtil.generateUUID();
            //设置响应信息
            StringMap policy=new StringMap();
    
            //两件事,确定url(js文件里有)加配置相应规则
            //配置七牛云的响应规则
            policy.put("returnBody",CommunityUtil.getJSONString(0));
            //生成上传凭证
            Auth auth=Auth.create(accessKey,secretKey);
            String uploadToken=auth.uploadToken(headerBucketName,fileName,3600,policy);
    
            model.addAttribute("uploadToken",uploadToken);
            model.addAttribute("fileName",fileName);
    
            return "/site/setting";
    
        }
    
        //更新头像路径
        @RequestMapping(path = "/header/url", method = RequestMethod.POST)
        @ResponseBody
        public String updateHeaderUrl(String fileName) {
            if (StringUtils.isBlank(fileName)) {
                return CommunityUtil.getJSONString(1, "文件名不能为空!");
            }
    
            String url = headerBucketUrl + "/" + fileName;
            userService.updateHeader(hostHolder.getUser().getId(), url);
    
            return CommunityUtil.getJSONString(0);
        }
    
    
    
        //废弃
        @LoginRequired
        @RequestMapping(path="/upload",method = RequestMethod.POST)
        public String uploadHeader(MultipartFile headerImage, Model model){
            if(headerImage==null){
                model.addAttribute("error","您还没有选择图片!");
                return "/site/setting";
            }
    
            String fileName=headerImage.getOriginalFilename();
            String suffix=fileName.substring(fileName.lastIndexOf("."));
            if(StringUtils.isBlank(suffix)){
                model.addAttribute("error","文件的格式不正确");
                return "/site/setting";
            }
    
            //生成随机文件名
            fileName= CommunityUtil.generateUUID()+suffix;
    
            //确定文件的存放路径
            File dest=new File(uploadPath+"/"+fileName);
    
    
            try {
                //存储文件
                headerImage.transferTo(dest);
            } catch (IOException e) {
                logger.error("上传文件失败:"+e.getMessage());
                throw new RuntimeException("上传文件失败,服务器发生异常",e);
            }
    
            //更新当前用户的头像的路径(web访问路径)
            // http://localhost:8080/community/user/header/xxx.png
            User user=hostHolder.getUser();
            String headerUrl=domain+contextPath+"/user/header/" + fileName;
            userService.updateHeader(user.getId(),headerUrl);
    
            return "redirect:/index";
        }
    
        //废弃
        //暴露一个访问接口给外部
        @RequestMapping(path="header/{fileName}",method=RequestMethod.GET)
        public void getHeader(@PathVariable("fileName")String fileName, HttpServletResponse response){
            //服务器存放路径
            fileName=uploadPath+"/"+fileName;
            //文件后缀
            String suffix=fileName.substring(fileName.lastIndexOf("."));
            //响应图片
            response.setContentType("image/"+suffix);
    
            try (
                    FileInputStream fis = new FileInputStream(fileName);
                    OutputStream os = response.getOutputStream();
            ) {
                byte[] buffer = new byte[1024];
                int b = 0;
                while ((b = fis.read(buffer)) != -1) {
                    os.write(buffer, 0, b);
                }
            } catch (IOException e) {
                logger.error("读取头像失败: " + e.getMessage());
            }
    
        }
    
    }
    
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    3.2view层

    修改setting.html,注释上传至服务器本地的代码,添加上传到七牛云的代码;新建setting.js。

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    setting.js:

    $(function(){
        $("#uploadForm").submit(upload);
    });
    
    function upload() {
        $.ajax({
            url: "http://upload-z1.qiniup.com",  //z1为华东地区
            method: "post",
            processData: false,
            contentType: false,
            data: new FormData($("#uploadForm")[0]),
            success: function(data) {
                if(data && data.code == 0) {
                    // 更新头像访问路径
                    $.post(
                        CONTEXT_PATH + "/user/header/url",
                        {"fileName":$("input[name='key']").val()},
                        function(data) {
                            data = $.parseJSON(data);
                            if(data.code == 0) {
                                window.location.reload();
                            } else {
                                alert(data.msg);
                            }
                        }
                    );
                } else {
                    alert("上传失败!");
                }
            }
        });
        return false;
    }
    
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    (1)用户发起/setting get请求,

    生成上传文件的名称(随机字符串),设置七牛云的响应规则,生成上传至凭证,

    		model.addAttribute("uploadToken",uploadToken);
            model.addAttribute("fileName",fileName);
    
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    响应/site/setting页面。

    (2)用户点击上传按钮,先向七牛云发送ajax 异步post请求(url:http://upload-z1.qiniup.com),凭证信息也会附带上传;响应七牛云返回的提示信息【凭证信息里包含有响应规则】,上传成供则再次发送 ajax 异步post请求来更新头像的访问路径,更新成功则重新加载/site/setting页面。

    更新头像的访问路径:更新数据库中的头像url地址(格式遵循七牛云的规范),返回成功code:0 JSON字符串。

    4.服务器直传

    4.1controller层

    ShareController类中修改share方法,废掉getShareImage方法。

    package com.gerrard.community.controller;
    
    import com.gerrard.community.entity.Event;
    import com.gerrard.community.event.EventProducer;
    import com.gerrard.community.util.CommunityConstant;
    import com.gerrard.community.util.CommunityUtil;
    import org.apache.commons.lang3.StringUtils;
    import org.slf4j.Logger;
    import org.slf4j.LoggerFactory;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.beans.factory.annotation.Value;
    import org.springframework.stereotype.Controller;
    import org.springframework.web.bind.annotation.PathVariable;
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.bind.annotation.RequestMethod;
    import org.springframework.web.bind.annotation.ResponseBody;
    
    import javax.servlet.http.HttpServletResponse;
    import java.io.File;
    import java.io.FileInputStream;
    import java.io.IOException;
    import java.io.OutputStream;
    import java.util.HashMap;
    import java.util.Map;
    @Controller
    public class ShareController implements CommunityConstant {
    
        private static final Logger logger= LoggerFactory.getLogger(ShareController.class);
    
    
        @Value("${community.path.domain}")
        private String domain;
    
        @Value("${server.servlet.context-path}")
        private String contextPath;
    
        @Value("${wk.image.storage}")
        private String wkImageStorage;
    
        @Value("${qiniu.bucket.share.url}")
        private String shareBucketUrl;
    
        @Autowired
        private EventProducer eventProducer;
    
        @RequestMapping(path="/share",method= RequestMethod.GET)
        @ResponseBody
        public String share(String htmlUrl){
            //文件名
            String fileName= CommunityUtil.generateUUID();
    
            //异步生成长图
            Event event=new Event()
                    .setTopic(TOPIC_SHARE)
                    .setData("htmlUrl",htmlUrl)
                    .setData("fileName",fileName)
                    .setData("suffix",".png");
    
            eventProducer.fireEvent(event);
    
            //返回访问路径
            Map<String,Object> map=new HashMap<>();
    //        map.put("shareUrl",domain+contextPath+"/share/image/"+fileName);
            map.put("shareUrl",shareBucketUrl+"/"+fileName);
    
            return  CommunityUtil.getJSONString(0,null,map);
    
        }
    
        //废弃
        //获取长图
        @RequestMapping(path="/share/image/{fileName}",method = RequestMethod.GET)
        public void getShareImage(@PathVariable("fileName")String fileName, HttpServletResponse response){
            if(StringUtils.isBlank(fileName)){
                throw new IllegalArgumentException("文件名不能为空!");
            }
    
            response.setContentType("image/png");
    
            File file=new File(wkImageStorage+"/"+fileName+".png");
    
            try {
                OutputStream os = response.getOutputStream();
                FileInputStream fis = new FileInputStream(file);
                byte[] buffer = new byte[1024];
                int b = 0;
                while ((b = fis.read(buffer)) != -1) {
                    os.write(buffer, 0, b);
                }
            } catch (IOException e) {
                logger.error("获取长图失败: " + e.getMessage());
            }
        }
    
    
    }
    
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    EventConsumer类中对handleShareMessage方法进行重构。

    package com.gerrard.community.event;
    
    import com.alibaba.fastjson.JSON;
    import com.alibaba.fastjson.JSONObject;
    import com.gerrard.community.entity.DiscussPost;
    import com.gerrard.community.entity.Event;
    import com.gerrard.community.entity.Message;
    import com.gerrard.community.service.DiscussPostService;
    import com.gerrard.community.service.ElasticsearchService;
    import com.gerrard.community.service.MessageService;
    import com.gerrard.community.util.CommunityConstant;
    import com.gerrard.community.util.CommunityUtil;
    import com.qiniu.common.QiniuException;
    import com.qiniu.common.Zone;
    import com.qiniu.http.Response;
    import com.qiniu.storage.Configuration;
    import com.qiniu.storage.UploadManager;
    import com.qiniu.util.Auth;
    import com.qiniu.util.StringMap;
    import org.apache.kafka.clients.consumer.ConsumerRecord;
    import org.slf4j.Logger;
    import org.slf4j.LoggerFactory;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.beans.factory.annotation.Value;
    import org.springframework.kafka.annotation.KafkaListener;
    import org.springframework.scheduling.concurrent.ThreadPoolTaskScheduler;
    import org.springframework.stereotype.Component;
    
    import java.io.File;
    import java.io.IOException;
    import java.util.Date;
    import java.util.HashMap;
    import java.util.Map;
    import java.util.concurrent.Future;
    
    @Component
    public class EventConsumer implements CommunityConstant {
        private static final Logger logger= LoggerFactory.getLogger(EventConsumer.class);
    
        @Autowired
        private MessageService messageService;
    
        @Autowired
        private DiscussPostService discussPostService;
    
        @Autowired
        private ElasticsearchService elasticsearchService;
    
        @Value("${wk.image.command}")
        private String wkImageCommand;
    
        @Value("${wk.image.storage}")
        private String wkImageStorage;
    
        @Value("${qiniu.key.access}")
        private String accessKey;
    
        @Value("${qiniu.key.secret}")
        private String secretKey;
    
        @Value("${qiniu.bucket.share.name}")
        private String shareBucketName;
    
        @Autowired
        private ThreadPoolTaskScheduler taskScheduler;
    
    
        //消费分享事件
        @KafkaListener(topics=TOPIC_SHARE)
        public void handleShareMessage(ConsumerRecord record){
            if (record == null || record.value() == null) {
                logger.error("消息的内容为空!");
                return;
            }
    
            Event event = JSONObject.parseObject(record.value().toString(), Event.class);
            if (event == null) {
                logger.error("消息格式错误!");
                return;
            }
    
            String htmlUrl = (String) event.getData().get("htmlUrl");
            String fileName = (String) event.getData().get("fileName");
            String suffix = (String) event.getData().get("suffix");
    
            String cmd = wkImageCommand + " --quality 75 "
                    + htmlUrl + " " + wkImageStorage + "/" + fileName + suffix;
            try {
                Runtime.getRuntime().exec(cmd);
                logger.info("生成长图成功: " + cmd);
            } catch (IOException e) {
                logger.error("生成长图失败: " + e.getMessage());
            }
    
            //启用定时器,监视该图片,一旦生成了,则上传至七牛云.
            UploadTask task=new UploadTask(fileName,suffix);
            Future future=taskScheduler.scheduleAtFixedRate(task,500);
            task.setFuture(future);
        }
        class UploadTask implements Runnable{
    
            //文件名称
            private String fileName;
            //文件后缀
            private String suffix;
            //启动任务的返回值
            private Future future;
            //开始时间
            private long startTime;
            //上传次数
            private int uploadTimes;
    
            public UploadTask(String fileName, String suffix) {
                this.fileName = fileName;
                this.suffix = suffix;
                this.startTime=System.currentTimeMillis();
            }
    
            public void setFuture(Future future) {
                this.future = future;
            }
    
            @Override
            public void run() {
                //生成失败
                if(System.currentTimeMillis()-startTime>30000){
                    logger.error("执行时间过长,终止任务:"+fileName);
                    future.cancel(true);
                    return;
                }
    
                //上传失败
                if(uploadTimes>=3){
                    logger.error("上传次数少过多,终止任务:"+fileName);
                    future.cancel(true);
                    return;
                }
                String path = wkImageStorage + "/" + fileName + suffix;
                File file = new File(path);
                if (file.exists()) {
                    logger.info(String.format("开始第%d次上传[%s].", ++uploadTimes, fileName));
                    // 设置响应信息
                    StringMap policy = new StringMap();
                    policy.put("returnBody", CommunityUtil.getJSONString(0));
                    // 生成上传凭证
                    Auth auth = Auth.create(accessKey, secretKey);
                    String uploadToken = auth.uploadToken(shareBucketName, fileName, 3600, policy);
                    // 指定上传机房
                    UploadManager manager = new UploadManager(new Configuration(Zone.zone0()));
                    try {
                        // 开始上传图片
                        Response response = manager.put(
                                path, fileName, uploadToken, null, "image/" + suffix, false);
                        // 处理响应结果
                        JSONObject json = JSONObject.parseObject(response.bodyString());
                        if (json == null || json.get("code") == null || !json.get("code").toString().equals("0")) {
                            logger.info(String.format("第%d次上传失败[%s].", uploadTimes, fileName));
                        } else {
                            logger.info(String.format("第%d次上传成功[%s].", uploadTimes, fileName));
                            future.cancel(true);
                        }
                    } catch (QiniuException e) {
                        logger.info(String.format("第%d次上传失败[%s].", uploadTimes, fileName));
                    }
                } else {
                    logger.info("等待图片生成[" + fileName + "].");
                }
    
            }
        }
    }
    
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    与上传头像功能不同,上传头像功能是在JS中编写,此处用Java编写。

    1.用户在浏览器中输入/share?htmlUrl=xxxxx,转到控制器的share方法,发布分享事件,异步生成长图,返回暴露的图片url地址JSON字符串至浏览器【url地址与前版本不一致】。

    2.异步生成长图:消费者消费分享事件,使用wkhtmltopdf工具异步生成长图,先在本地生成图片,启用定时器,监视该图片,一旦生成了,则上传至七牛云。

    3.用户在浏览器地址栏输入图片url访问地址,访问该图片。

    问题:七牛云外链链接一个是直接看到图片,一个是要下载?

    5.功能测试

    5.1上传头像功能测试

    上传了一个pdf,可以上传成功,但网页中头像信息显示不出。

    NowCoder_37_7

    NowCoder_37_8

    上传图片:

    NowCoder_37_9

    在七牛云中查询图片信息:

    NowCoder_37_10

    查看user MySQL数据库信息:

    NowCoder_37_11

    5.2服务器直传功能测试

    在浏览器地址栏中输入:http://localhost:8080/community/share?htmlUrl=https://www.baidu.com

    InkedNowCoder_37_12

    本次访问未创建成功

    NowCoder_37_13

    再访问一次:

    NowCoder_37_14

    等待一会儿根据响应的地址访问该图片:

    NowCoder_37_15

    在七牛云中查看图片:

    NowCoder_37_16

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  • 原文地址:https://blog.csdn.net/weixin_45700663/article/details/126002935