缩略图云功能失败并显示“错误：EBUSY：资源繁忙或锁定，rmdir '/tmp/thumbs' at Error (native)”

Question

我的 Firebase 云函数失败并出现以下错误：

Error: EBUSY: resource busy or locked, rmdir '/tmp/thumbs' at Error (native)

通过我的功能，我为上传的图片创建缩略图并将它们保存到 Firebase 存储。我构建以下代码的方式一切正常（除了每个函数调用都失败）。但我担心由于 tmp 文件夹中的旧文件没有被删除，我的 tmp 文件夹会填满不必要的文件。

import * as functions from 'firebase-functions'

import {tmpdir} from 'os'
import {join, dirname} from 'path'

import * as sharp from 'sharp'
import * as fs from 'fs-extra'
import * as admin from "firebase-admin"

const storage = admin.storage()

/* Saves thumbnails for all userPics uploaded to Google Cloud Storage */
export const thumbnailCreator = functions.storage
    .object()
    .onFinalize(async object => {
        const bucket = storage.bucket(object.bucket)
        const filePath = object.name
        const fileName = filePath.split('/').pop()
        const bucketDir = dirname(filePath)
        const workingDir = join(tmpdir(), 'thumbs')

        /* Temporary: Creates a random number for the sourceFilePath
        * because currently bucket.file(filePath).download does not seem to overwrite
        * existing files and fs.rmdir(workingDir) does throw that error... */

        const randomNr = Math.random().toString(36).substring(2, 15) +
            Math.random().toString(36).substring(2, 15)

        const tmpFilePath = join(workingDir, `source_${randomNr}.png`)

        if (!object.contentType.includes('image')) {
            console.log('exiting function (no image)')
            return false
        }

        if (fileName.includes('thumb@')) {
            console.log('exiting function (already a thumbnail')
            return false
        }

        // 1. Ensure thumbnail dir exists
        await fs.ensureDir(workingDir)

        // 2. Download Source File
        await bucket.file(filePath).download({
            destination: tmpFilePath
        })

        // 3. Resize the images and define an array of upload promises
        const sizes = [64, 128, 256, 512]

        const uploadPromises = sizes.map(async size => {
            const thumbName = `thumb@${size}_${fileName}`
            const thumbPath = join(workingDir, thumbName)

            // Resize source image
            await sharp(tmpFilePath)
                .rotate()
                .resize(size, size)
                .toFile(thumbPath)

            // Upload to GCS
            const file = await bucket.upload(thumbPath, {
                destination: join(bucketDir, thumbName),
                predefinedAcl: 'publicRead'
            })

        })

        // 4. Run the upload operations
        await Promise.all(uploadPromises)

        // 5. Cleanup remove the tmp/thumbs from the filesystem
        return fs.rmdir(workingDir)
        // TODO: This fails every time -> also tried with fs.remove(workingDir), same issue.

    })

如您所见，我处理它的方式是为 source.png 的文件名提供 GUID，因为下次调用该函数时，它不会在执行 bucket.file(filePath).download() 时覆盖已下载的文件。

但我想清理我的 tmp 文件夹，但我不知道为什么该文件夹“忙或被锁定”。有没有办法在尝试删除之前解锁它？

更新 - 来自 DOUG 的解决方案

正如道格在下面回答的那样，在删除文件夹之前删除所有文件是可行的。所以我最终这样做了：

// 5. Cleanup remove the tmp/thumbs from the filesystem
await fs.emptyDir(workingDir)
await fs.remove(workingDir)

Answer 1

我不知道这是否会导致 EBUSY，但是 rmdir（节点的版本和同名的 unix 命令行）要求目录在调用之前为空。您将文件留在了那里，这可能会导致 rmdir 失败。尝试单独删除每个生成的文件，然后删除目录。