1.服务端代码

public RestResponse aliossUploadUrlCallback(AliOssUploadUrlReqForm reqForm) throws ModelChangeException, UnsupportedEncodingException {

        FileUploadInfo info = new FileUploadInfo();

        String dir = reqForm.getUserId() + "/";
        String fileName = uuidName(reqForm.getFileName());
        String key = dir + fileName;
        String host = ossEndpoint.replace("https://", "https://" + bucket + "."); // 提交表单的URL为bucket域名

        // 创建OSSClient实例。
        OSS ossClient = new OSSClientBuilder().build(ossEndpoint, ossAccessId, ossAccessKey);
        try {
            long expireTime = 30;
            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();
            policyConds.addConditionItem(PolicyConditions.COND_CONTENT_LENGTH_RANGE, 0, 1048576000);
            policyConds.addConditionItem(MatchMode.StartWith, PolicyConditions.COND_KEY, dir);

            String postPolicy = ossClient.generatePostPolicy(expiration, policyConds);
            byte[] binaryData = postPolicy.getBytes("utf-8");
            String encodedPolicy = BinaryUtil.toBase64String(binaryData);
            String postSignature = ossClient.calculatePostSignature(postPolicy);

            /*callback*/
            JSONObject jasonCallback = new JSONObject();
            /*配置回调地址*/
            jasonCallback.put("callbackUrl", callbackUrl);
            jasonCallback.put("callbackBody",
      "key=${object}&size=${size}&mimeType=${mimeType}&height=${imageInfo.height}&width=${imageInfo.width}");
            jasonCallback.put("callbackBodyType", "application/x-www-form-urlencoded");
            String base64CallbackBody = BinaryUtil.toBase64String(jasonCallback.toString().getBytes());

            info.setOSSAccessKeyId(ossAccessId);
            info.setDir(dir);
            info.setPolicy(encodedPolicy);
            info.setSignature(postSignature);
            info.setKey(key);

            info.setHost(host);
            info.setExpire(expireEndTime);
            info.setCallback(base64CallbackBody);

            File file = fileFactory.create(key, bucket, ossEndpoint);
            fileService.save(file);

            info.setFile(file.model());

        } catch (Exception e) {
            log.error(e.getMessage(), e);
            return RestResponse.failure(ResCodeMsg.RES_EXCEPTION_SYSTEM)
                    .setAny(RESPONSE_KEY_ERROR, e.getMessage());
        } finally {
            ossClient.shutdown();
        }

        return RestResponse.success().setAny(RESPONSE_KEY_FILE_UPLOAD_INFO, info);
    }

2.前端vue实现代码

<template>
    <div>
        <p>{{uploadInfo}}</p>
        <input type="file" @change="upload($event)">
    </div>
</template>

<script>
    export default {
        name: "FileUpload",
        data() {
            return {
                uploadInfo: ''
            }
        }, mounted: async function () {
          /*获取上传oss需要用到的表单信息*/
            await this.axios.post("http://****/aliossUploadUrlCallback").then(res => {
                console.log(res.data.file)
                this.uploadInfo = res.data.file
            })
        }, methods: {
            upload(e) {
                console.log(e.target.files[0])
                const file = e.target.files[0]
                const header = {
                    headers: {
                        'Content-Type': 'multipart/form-data;',
                    }
                }
                console.log(this.uploadInfo)
                let formData = new FormData
                formData.append("key", this.uploadInfo.key)
                formData.append("name", file.name)
                formData.append("OSSAccessKeyId", this.uploadInfo.OSSAccessKeyId)
                formData.append("policy", this.uploadInfo.policy)
                formData.append("signature", this.uploadInfo.signature)

                //formData.append("expire",this.uploadInfo.expire)
                formData.append("callback", this.uploadInfo.callback)

                formData.append("file", file)
 
              /*上传OSS*/
                this.axios.post(this.uploadInfo.host, formData, header).then(res => {
                    console.log(res)
                })
            }
        }
    }
</script>

<style scoped>

</style>

3.回调

前端上传完图片，后台回调地址就会收到oss的回调

注意：上传OSS时文件要放在表单的最后一个域，key要放在表单的第一个域