46 lines
1.2 KiB
JavaScript
46 lines
1.2 KiB
JavaScript
const crypto = require("crypto-js");
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class uploadOssHelper {
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constructor(options) {
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this.accessKeyId = options.accessKeyId;
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this.accessKeySecret = options.accessKeySecret;
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// 限制参数的生效时间，单位为小时，默认值为1。
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this.timeout = options.timeout || 1;
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// 限制上传文件的大小，单位为MB，默认值为10。
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this.maxSize = options.maxSize || 10;
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}
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createUploadParams() {
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const policy = this.getPolicyBase64();
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const signature = this.signature(policy);
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return {
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OSSAccessKeyId: this.accessKeyId,
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policy: policy,
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signature: signature,
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};
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}
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getPolicyBase64() {
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let date = new Date();
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// 设置policy过期时间。
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date.setHours(date.getHours() + this.timeout);
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let srcT = date.toISOString();
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const policyText = {
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expiration: srcT,
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conditions: [
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// 限制上传文件大小。
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["content-length-range", 0, this.maxSize * 1024 * 1024],
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],
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};
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const buffer = new Buffer(JSON.stringify(policyText));
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return buffer.toString("base64");
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}
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signature(policy) {
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return crypto.enc.Base64.stringify(
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crypto.HmacSHA1(policy, this.accessKeySecret)
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);
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}
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}
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module.exports = uploadOssHelper; |