阿里云OSS的使用

1、第一步：阿里云申请账号：（以下可能有点混搭，因为涉及到钱。。。但是步骤是没错的）

搜索 RAM-> 进入 RAM 访问控制。

创建用户：


授予权限

进入OSS控制台

信息确认无误后，点击确定：
记录地域地址：

oss-cn-beijing.aliyuncs.com
oss-cn-beijing-internal.aliyuncs.com
oss-cn-beijing-internal.aliyuncs.com

获得access-key和secret-key

2、Springboot整合OSS开发

2.1、maven依赖

<dependency>
	<groupId>com.alibaba.cloud</groupId>
	<artifactId>spring-cloud-starter-alicloud-oss</artifactId>
</dependency>

2.2、增加OSS配置文件

spring:
    cloud:
        alicloud:
            access-key: 上面获得的access-key
            secret-key: 上面获得的secret-key
            oos:
                endpoint: oss-cn-beijing.aliyuncs.com

2.3、文件上传接口开发

package com.zhz.controller;

import cn.hutool.core.date.DateUtil;
import com.alibaba.fastjson.JSONObject;
import com.aliyun.oss.OSS;
import com.aliyun.oss.common.utils.BinaryUtil;
import com.aliyun.oss.model.MatchMode;
import com.aliyun.oss.model.PolicyConditions;
import com.zhz.model.R;
import io.swagger.annotations.Api;
import io.swagger.annotations.ApiImplicitParam;
import io.swagger.annotations.ApiImplicitParams;
import io.swagger.annotations.ApiOperation;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;

import java.io.IOException;
import java.util.Date;
import java.util.LinkedHashMap;
import java.util.Map;

/**
 * 完成文件上传的功能
 */
@RestController
@Api(tags = "文件上传的控制器")
public class FileController {
     

    // spring-cloud-alibaba-oss 会自动的注入该对象,爆红也不用理
    @Autowired
    private OSS ossClient;

    @Value("${spring.cloud.alicloud.access-key}")
    private String accessId;

    @Value("${oss.bucket.name:coin-exchange-imgs1}")
    private String bucketName;

    @Value("${spring.cloud.alicloud.oss.endpoint}")
    private String endPoint;


    @Value("${oss.callback.url:http://coinoss.free.idcfengye.com}")//nginx负载均衡地址
    private String ossCallbackUrl; //


    @ApiOperation(value = "上传文件")
    @PostMapping("/image/AliYunImgUpload")
    @ApiImplicitParams({
     
            @ApiImplicitParam(name = "file", value = "你要上传的文件")
    })
    public R<String> fileUpload(@RequestParam("file") MultipartFile file) throws IOException {
     

        /**
         * 1 bucketName
         * 2 文件的名称 日期 +原始的文件名（uuid）来做
         * 3 文件的输入流
         */
        // 2020-10-10->2020/10/10/xxx.jpg
        String fileName = DateUtil.today().replaceAll("-", "/") + "/" + file.getOriginalFilename();
        ossClient.putObject(bucketName, fileName, file.getInputStream());
        // https://coin-exchange-imgs.oss-cn-beijing.aliyuncs.com/2020/10/10/xxx.jpg
        // https://coin-exchange-imgs.oss-cn-beijing.aliyuncs.com/2020/10/10/banner9.jpg
        return R.ok("https://" + bucketName + "." + endPoint + "/" + fileName); //能使用浏览器访问到文件路径http://xxx.com/路径
    }


    @GetMapping("/image/pre/upload")//自己的地址
    @ApiOperation(value = "文件的上传获取票据")
    public R<Map<String,String>> preUploadPolicy() {
     
        String dir = DateUtil.today().replaceAll("-", "/") + "/";
        Map<String, String> policy = getPolicy(30L, 3 * 1024 * 1024L, dir);
        return R.ok(policy) ;
    }

    private Map<String, String> getPolicy(long expireTime, long maxFileSize, String dir) {
     
        try {
     
            long expireEndTime = System.currentTimeMillis() + expireTime * 1000;
            Date expiration = new Date(expireEndTime);
            // PostObject请求最大可支持的文件大小为5 GB，即CONTENT_LENGTH_RANGE为5*1024*1024*1024。
            PolicyConditions policyConds = new PolicyConditions();
            // 设置上传文件的最大的体积
            policyConds.addConditionItem(PolicyConditions.COND_CONTENT_LENGTH_RANGE, 0, maxFileSize);
            // 设置上传文件上传到那个文件夹
            policyConds.addConditionItem(MatchMode.StartWith, PolicyConditions.COND_KEY, dir);

            String postPolicy = ossClient.generatePostPolicy(expiration, policyConds); // 设置该Policy(票据) 有效时间
            byte[] binaryData = postPolicy.getBytes("utf-8");
            String encodedPolicy = BinaryUtil.toBase64String(binaryData);
            String postSignature = ossClient.calculatePostSignature(postPolicy);

            // 返回值
            Map<String, String> respMap = new LinkedHashMap<String, String>();
            respMap.put("accessid", accessId); // 设置我们之前的accessKey
            respMap.put("policy", encodedPolicy);
            respMap.put("signature", postSignature);
            respMap.put("dir", dir);
            respMap.put("host", "https://" + bucketName +"."+ endPoint); // 设置 上传的Host https://bulkname.endpoint
            respMap.put("expire", String.valueOf(expireEndTime / 1000));
            // respMap.put("expire", formatISO8601Date(expiration));

            JSONObject jasonCallback = new JSONObject();

            jasonCallback.put("callbackUrl", ossCallbackUrl); // 当我们的前端把文件上传到oss 服务器成功后
            // ,oss 服务器会想回调的callbackUrl(公网) 发一个post请求来告诉后端服务器用户上传文件的情况
            jasonCallback.put("callbackBody",
                    "filename=${object}&size=${size}&mimeType=${mimeType}&height=${imageInfo.height}&width=${imageInfo.width}");
            jasonCallback.put("callbackBodyType", "application/x-www-form-urlencoded");
            String base64CallbackBody = BinaryUtil.toBase64String(jasonCallback.toString().getBytes());
            respMap.put("callback", base64CallbackBody);
            return respMap;
        } catch (Exception e) {
     
            e.printStackTrace();
        }
        return null;
    }

}