eggjs 上传文件

'use strict';

const Controller = require('egg').Controller;

// 文件存储

const fs = require('fs');

const path = require('path');

const awaitWriteStream = require('await-stream-ready').write;

const sendToWormhole = require('stream-wormhole');



class UploadController extends Controller {

    /**

     * 

     * @param {*} stream  传入的Buffer流

     * @param {*} paths 保存的路径

     * @param {*} multiple 是否多文件

     * @param {*} files 多文件返回

     */

    async upload(stream, paths = "app/public/img", multiple = false, files = []) {

        const filename = Math.random().toString(36).substr(2) + new Date().getTime() + path.extname(stream.filename).toLocaleLowerCase();

        const target = path.join(this.config.baseDir, paths, filename);

        const writeStream = fs.createWriteStream(target);

        try {

            await awaitWriteStream(stream.pipe(writeStream));

            return !!multiple ? files.push(filename) : filename;

        } catch (err) {

            await sendToWormhole(stream);

            return { code: 422, message: '上传失败，请重试！' }

        }

    };

    // 单文件

    async create() {

        const ctx = this.ctx;

        // 获取流

        const stream = await ctx.getFileStream();

        // 生成文件名

        const filename = Math.random().toString(36).substr(2) + new Date().getTime() + path.extname(stream.filename).toLocaleLowerCase();

        // pipe流写入信息

        const target = path.join(this.config.baseDir, 'app/public/img', filename);

        const writeStream = fs.createWriteStream(target);

        try {

            // 保存

            await awaitWriteStream(stream.pipe(writeStream));

        } catch (err) {

            // 保存失败销毁stream 不然接口会pending到超时

            await sendToWormhole(stream);

            this.ctx.body = { code: 422, message: '上传失败，请重试！' }

            throw err;

        }

        this.ctx.body = {

            data: filename

        };

    };

    // 多文件

    async creates() {

        const ctx = this.ctx;

        // 获取文件流组

        const streams = ctx.multipart();

        let stream;

        // 保存返回的文件信息

        let files = [];

        // 其他form 参数

        let fields = {}

        while ((stream = await streams()) != null) {

            // 检查是否有其他参数 如果有写入 这里做案例 不做处理

            if (stream.length) {

                fields[stream[0]] = stream[1]

            } else {

                // 空文件处理

                if (!stream.filename) {

                    return;

                }

                // 设置文件名称

                const filename = Math.random().toString(36).substr(2) + new Date().getTime() + path.extname(stream.filename).toLocaleLowerCase();

                // pipe 设置

                const target = path.join(this.config.baseDir, 'app/public/img', filename);

                const writeStream = fs.createWriteStream(target);

                try {

                    // 保存

                    await awaitWriteStream(stream.pipe(writeStream));

                    // 写入数组

                    files.push({ filename, path: `/img/${filename}` })

                } catch (err) {

                    await sendToWormhole(stream);

                    this.ctx.body = { code: 422, message: '上传失败，请重试！' }

                    throw err;

                }

            }

        }

        this.ctx.body = {

            data: { files, fields }

        };

    }

}



module.exports = UploadController