如果目录不存在,下面的方法是否正确?

它应该对脚本具有完全的权限,并且其他人可以阅读。

var dir = __dirname + '/upload';
if (!path.existsSync(dir)) {
    fs.mkdirSync(dir, 0744);
}

当前回答

下面是一个递归创建目录的小函数:

const createDir = (dir) => {
  // This will create a dir given a path such as './folder/subfolder' 
  const splitPath = dir.split('/');
  splitPath.reduce((path, subPath) => {
    let currentPath;
    if(subPath != '.'){
      currentPath = path + '/' + subPath;
      if (!fs.existsSync(currentPath)){
        fs.mkdirSync(currentPath);
      }
    }
    else{
      currentPath = subPath;
    }
    return currentPath
  }, '')
}

其他回答

使用Node.js 10 + ES6:

import path from 'path';
import fs from 'fs';

(async () => {
  const dir = path.join(__dirname, 'upload');

  try {
    await fs.promises.mkdir(dir);
  } catch (error) {
    if (error.code === 'EEXIST') {
      // Something already exists, but is it a file or directory?
      const lstat = await fs.promises.lstat(dir);

      if (!lstat.isDirectory()) {
        throw error;
      }
    } else {
      throw error;
    }
  }
})();

我的解决方案

CommonJS


var fs = require("fs");

var dir = __dirname + '/upload';

// if (!fs.existsSync(dir)) {
//   fs.mkdirSync(dir);
// }

if (!fs.existsSync(dir)) {
  fs.mkdirSync(dir, {
    mode: 0o744,
  });
  // mode's default value is 0o744
}

ESM

更新包。json配置

{
  //...
  "type": "module",
  //...
}
import fs from "fs";
import path from "path";

// create one custom `__dirname`, because it not exist in es-module env ⚠️
const __dirname = path.resolve();

const dir = __dirname + '/upload';

if (!fs.existsSync(dir)) {
  fs.mkdirSync(dir);
}

// OR
if (!fs.existsSync(dir)) {
  fs.mkdirSync(dir, {
    mode: 0o744,
  });
  // mode's default value is 0o744
}

refs

https://nodejs.org/api/fs.html#fsexistssyncpath

https://github.com/nodejs/help/issues/2907#issuecomment-671782092

从文档中可以看出,这是你异步(和递归)做这件事的方式:

const fs = require('fs');
const fsPromises = fs.promises;

fsPromises.access(dir, fs.constants.F_OK)
   .catch(async() => {
                await fs.mkdir(dir, { recursive: true }, function(err) {
                    if (err) {
                      console.log(err)
                    }
                  })
    });

我想添加一个TypeScript承诺重构josh3736的答案。

它做的是同样的事情,有同样的边界情况。它只是碰巧使用Promises, TypeScript typedefs,并使用“use strict”。

// https://en.wikipedia.org/wiki/File_system_permissions#Numeric_notation
const allRWEPermissions = parseInt("0777", 8);

function ensureFilePathExists(path: string, mask: number = allRWEPermissions): Promise<void> {
    return new Promise<void>(
        function(resolve: (value?: void | PromiseLike<void>) => void,
            reject: (reason?: any) => void): void{
            mkdir(path, mask, function(err: NodeJS.ErrnoException): void {
                if (err) {
                    if (err.code === "EEXIST") {
                        resolve(null); // Ignore the error if the folder already exists
                    } else {
                        reject(err); // Something else went wrong
                    }
                } else {
                    resolve(null); // Successfully created folder
                }
            });
    });
}

异步执行此操作的函数(从使用同步函数的SO上的类似答案调整,我现在找不到)

// ensure-directory.js
import { mkdir, access } from 'fs'

/**
 * directoryPath is a path to a directory (no trailing file!)
 */
export default async directoryPath => {
  directoryPath = directoryPath.replace(/\\/g, '/')

  // -- preparation to allow absolute paths as well
  let root = ''
  if (directoryPath[0] === '/') {
    root = '/'
    directoryPath = directoryPath.slice(1)
  } else if (directoryPath[1] === ':') {
    root = directoryPath.slice(0, 3) // c:\
    directoryPath = directoryPath.slice(3)
  }

  // -- create folders all the way down
  const folders = directoryPath.split('/')
  let folderPath = `${root}`
  for (const folder of folders) {
    folderPath = `${folderPath}${folder}/`

    const folderExists = await new Promise(resolve =>
      access(folderPath, error => {
        if (error) {
          resolve(false)
        }
        resolve(true)
      })
    )

    if (!folderExists) {
      await new Promise((resolve, reject) =>
        mkdir(folderPath, error => {
          if (error) {
            reject('Error creating folderPath')
          }
          resolve(folderPath)
        })
      )
    }
  }
}