关于使用fs.readdir进行异步目录搜索有什么想法吗?我意识到我们可以引入递归,并调用read目录函数来读取下一个目录,但我有点担心它不是异步的…

什么好主意吗?我已经看了node-walk,它很棒,但它不能像readdir那样只给我数组中的文件。虽然

寻找这样的输出…

['file1.txt', 'file2.txt', 'dir/file3.txt']

当前回答

There are basically two ways of accomplishing this. In an async environment you'll notice that there are two kinds of loops: serial and parallel. A serial loop waits for one iteration to complete before it moves onto the next iteration - this guarantees that every iteration of the loop completes in order. In a parallel loop, all the iterations are started at the same time, and one may complete before another, however, it is much faster than a serial loop. So in this case, it's probably better to use a parallel loop because it doesn't matter what order the walk completes in, just as long as it completes and returns the results (unless you want them in order).

一个平行循环看起来是这样的:

var fs = require('fs');
var path = require('path');
var walk = function(dir, done) {
  var results = [];
  fs.readdir(dir, function(err, list) {
    if (err) return done(err);
    var pending = list.length;
    if (!pending) return done(null, results);
    list.forEach(function(file) {
      file = path.resolve(dir, file);
      fs.stat(file, function(err, stat) {
        if (stat && stat.isDirectory()) {
          walk(file, function(err, res) {
            results = results.concat(res);
            if (!--pending) done(null, results);
          });
        } else {
          results.push(file);
          if (!--pending) done(null, results);
        }
      });
    });
  });
};

一个串行循环看起来像这样:

var fs = require('fs');
var path = require('path');
var walk = function(dir, done) {
  var results = [];
  fs.readdir(dir, function(err, list) {
    if (err) return done(err);
    var i = 0;
    (function next() {
      var file = list[i++];
      if (!file) return done(null, results);
      file = path.resolve(dir, file);
      fs.stat(file, function(err, stat) {
        if (stat && stat.isDirectory()) {
          walk(file, function(err, res) {
            results = results.concat(res);
            next();
          });
        } else {
          results.push(file);
          next();
        }
      });
    })();
  });
};

并且在你的主目录中测试它(警告:如果你的主目录中有很多东西,结果列表将会非常大):

walk(process.env.HOME, function(err, results) {
  if (err) throw err;
  console.log(results);
});

编辑:改进的示例。

其他回答

我喜欢上面chjj的答案,如果没有那个开始,我就无法创建我的并行循环版本。

var fs = require("fs");

var tree = function(dir, done) {
  var results = {
        "path": dir
        ,"children": []
      };
  fs.readdir(dir, function(err, list) {
    if (err) { return done(err); }
    var pending = list.length;
    if (!pending) { return done(null, results); }
    list.forEach(function(file) {
      fs.stat(dir + '/' + file, function(err, stat) {
        if (stat && stat.isDirectory()) {
          tree(dir + '/' + file, function(err, res) {
            results.children.push(res);
            if (!--pending){ done(null, results); }
          });
        } else {
          results.children.push({"path": dir + "/" + file});
          if (!--pending) { done(null, results); }
        }
      });
    });
  });
};

module.exports = tree;

我也创建了一个Gist。欢迎评论。我仍然在NodeJS领域起步,所以这是我希望学到更多的一种方式。

如果你想使用npm包,扳手是很好的选择。

var wrench = require("wrench");

var files = wrench.readdirSyncRecursive("directory");

wrench.readdirRecursive("directory", function (error, files) {
    // live your dreams
});

编辑(2018): 作者在2015年弃用了这个包:

扳手.js已弃用,并且在相当长的一段时间内没有更新。我强烈建议使用fs-extra来执行任何额外的文件系统操作。

qwtel的答案变体,在TypeScript中

import { resolve } from 'path';
import { readdir } from 'fs/promises';

async function* getFiles(dir: string): AsyncGenerator<string> {
    const entries = await readdir(dir, { withFileTypes: true });
    for (const entry of entries) {
        const res = resolve(dir, entry.name);
        if (entry.isDirectory()) {
            yield* getFiles(res);
        } else {
            yield res;
        }
    }
}

短小、现代、高效:

import {readdir} from 'node:fs/promises'
import {join} from 'node:path'

const deepReadDir = async (dirPath) => await Promise.all(
  (await readdir(dirPath, {withFileTypes: true})).map(async (dirent) => {
    const path = join(dirPath, dirent.name)
    return dirent.isDirectory() ? await deepReadDir(path) : path
  }),
)

特别感谢函数提示使用{withFileTypes: true}。


这将自动将每个嵌套路径折叠成一个新的嵌套数组。例如,如果:

await deepReadDir('src')

返回如下内容:

[
  [
    'src/client/api.js',
    'src/client/http-constants.js',
    'src/client/index.html',
    'src/client/index.js',
    [ 'src/client/res/favicon.ico' ],
    'src/client/storage.js'
  ],
  [ 'src/crypto/keygen.js' ],
  'src/discover.js',
  [
    'src/mutations/createNewMutation.js',
    'src/mutations/newAccount.js',
    'src/mutations/transferCredit.js',
    'src/mutations/updateApp.js'
  ],
  [
    'src/server/authentication.js',
    'src/server/handlers.js',
    'src/server/quick-response.js',
    'src/server/server.js',
    'src/server/static-resources.js'
  ],
  [ 'src/util/prompt.js', 'src/util/safeWriteFile.js' ],
  'src/util.js'
]

但如果你想,你可以很容易地把它压平:

(await deepReadDir('src')).flat(Number.POSITIVE_INFINITY)
[
  'src/client/api.js',
  'src/client/http-constants.js',
  'src/client/index.html',
  'src/client/index.js',
  'src/client/res/favicon.ico',
  'src/client/storage.js',
  'src/crypto/keygen.js',
  'src/discover.js',
  'src/mutations/createNewMutation.js',
  'src/mutations/newAccount.js',
  'src/mutations/transferCredit.js',
  'src/mutations/updateApp.js',
  'src/server/authentication.js',
  'src/server/handlers.js',
  'src/server/quick-response.js',
  'src/server/server.js',
  'src/server/static-resources.js',
  'src/util/prompt.js',
  'src/util/safeWriteFile.js',
  'src/util.js'
]

使用承诺(Q)以函数式风格解决此问题:

var fs = require('fs'),
    fsPath = require('path'),
    Q = require('q');

var walk = function (dir) {
  return Q.ninvoke(fs, 'readdir', dir).then(function (files) {

    return Q.all(files.map(function (file) {

      file = fsPath.join(dir, file);
      return Q.ninvoke(fs, 'lstat', file).then(function (stat) {

        if (stat.isDirectory()) {
          return walk(file);
        } else {
          return [file];
        }
      });
    }));
  }).then(function (files) {
    return files.reduce(function (pre, cur) {
      return pre.concat(cur);
    });
  });
};

它返回一个数组的promise,所以你可以这样使用它:

walk('/home/mypath').then(function (files) { console.log(files); });