【阿里云】对象存储服务oss实现图片上传

思路就是
用户发送上传Policy请求到应用服务器。
应用服务器返回上传Policy和签名给用户。
用户直接上传数据到OSS。

这样上传图片的时候不用发文件流传输到后台 然后后台进行处理 减轻了后台压力。

1.引入jar包

<!-- 阿里云OSS -->
        <dependency>
            <groupId>com.aliyun.oss</groupId>
            <artifactId>aliyun-sdk-oss</artifactId>
            <version>2.5.0</version>
        </dependency>

2. 控制层

import com.xiepanpan.gmall.admin.oms.component.OssCompent;
import com.xiepanpan.gmall.to.CommonResult;
import com.xiepanpan.gmall.to.OssPolicyResult;
import io.swagger.annotations.Api;
import io.swagger.annotations.ApiOperation;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.*;


/**
 * Oss相关操作接口
 *
 *
 */
//@CrossOrigin(origins = "www.baidu.com")
@CrossOrigin
@Controller
@Api(tags = "OssController",description = "Oss管理")
@RequestMapping("/aliyun/oss")
public class OssController {
	@Autowired
	private OssCompent ossComponent;

	@ApiOperation(value = "oss上传签名生成")
	@GetMapping(value = "/policy")
	@ResponseBody
	public Object policy() {
		OssPolicyResult policy = ossComponent.policy();
		return new CommonResult().success(policy);
	}

}

3.

package com.xiepanpan.gmall.admin.oms.component;

import com.aliyun.oss.OSSClient;
import com.aliyun.oss.common.utils.BinaryUtil;
import com.aliyun.oss.internal.OSSUtils;
import com.aliyun.oss.model.MatchMode;
import com.aliyun.oss.model.PolicyConditions;
import com.xiepanpan.gmall.to.OssPolicyResult;
import lombok.extern.slf4j.Slf4j;
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.context.annotation.Bean;
import org.springframework.stereotype.Service;

import javax.servlet.http.HttpServletRequest;
import java.text.SimpleDateFormat;
import java.util.Date;

/**
 * Created by atguigu 5/17.
 */
@Slf4j
@Service
public class OssCompent {

	@Value("${aliyun.oss.policy.expire}")
	private int ALIYUN_OSS_EXPIRE;
	@Value("${aliyun.oss.maxSize}")
	private int ALIYUN_OSS_MAX_SIZE;
	@Value("${aliyun.oss.bucketName}")
	private String ALIYUN_OSS_BUCKET_NAME;
	@Value("${aliyun.oss.endpoint}")
	private String ALIYUN_OSS_ENDPOINT;
	@Value("${aliyun.oss.dir.prefix}")
	private String ALIYUN_OSS_DIR_PREFIX;

	@Value("${aliyun.oss.accessKeyId}")
	private String ALIYUN_OSS_KEY;
	@Value("${aliyun.oss.accessKeySecret}")
	private String ALIYUN_OSS_SECRET_KEY;



	@Autowired
	private OSSClient ossClient;

	/**
	 * 签名生成
	 */
	public OssPolicyResult policy() {


		OssPolicyResult result = new OssPolicyResult();
		// 存储目录
		SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMdd");
		String dir = ALIYUN_OSS_DIR_PREFIX+sdf.format(new Date());
		// 签名有效期
		long expireEndTime = System.currentTimeMillis() + ALIYUN_OSS_EXPIRE * 1000;
		Date expiration = new Date(expireEndTime);
		// 文件大小
		long maxSize = ALIYUN_OSS_MAX_SIZE * 1024 * 1024;
		// 提交节点
		String action = "http://" + ALIYUN_OSS_BUCKET_NAME + "." + ALIYUN_OSS_ENDPOINT;
		try {
			PolicyConditions policyConds = new PolicyConditions();
			policyConds.addConditionItem(PolicyConditions.COND_CONTENT_LENGTH_RANGE, 0, maxSize);
			policyConds.addConditionItem(MatchMode.StartWith, PolicyConditions.COND_KEY, dir);
			String postPolicy = ossClient.generatePostPolicy(expiration, policyConds);
			byte[] binaryData = postPolicy.getBytes("utf-8");
			String policy = BinaryUtil.toBase64String(binaryData);
			String signature = ossClient.calculatePostSignature(postPolicy);
			// 返回结果
			result.setAccessKeyId(ossClient.getCredentialsProvider().getCredentials().getAccessKeyId());
			result.setPolicy(policy);
			result.setSignature(signature);
			result.setDir(dir);
			result.setHost(action);
		} catch (Exception e) {
			log.error("签名生成失败", e);
		}
		return result;
	}

	@Bean
	public OSSClient ossClient(){

		//public OSSClient(String endpoint, String accessKeyId, String secretAccessKey)
		OSSClient ossClient = new OSSClient(ALIYUN_OSS_ENDPOINT, ALIYUN_OSS_KEY, ALIYUN_OSS_SECRET_KEY);
		return ossClient;
	}




}

官方文档：
https://help.aliyun.com/document_detail/31926.html?spm=a2c6h.13066369.0.0.3e7f61ccZixXt8

来源：CSDN

作者：周杰伦本人

链接：https://blog.csdn.net/sdaujsj1/article/details/103770088