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

使用async/await,这应该工作:

const FS = require('fs');
const readDir = promisify(FS.readdir);
const fileStat = promisify(FS.stat);

async function getFiles(dir) {
    let files = await readDir(dir);

    let result = files.map(file => {
        let path = Path.join(dir,file);
        return fileStat(path).then(stat => stat.isDirectory() ? getFiles(path) : path);
    });

    return flatten(await Promise.all(result));
}

function flatten(arr) {
    return Array.prototype.concat(...arr);
}

你可以用蓝鸟。许诺或许诺:

/**
 * Returns a function that will wrap the given `nodeFunction`. Instead of taking a callback, the returned function will return a promise whose fate is decided by the callback behavior of the given node function. The node function should conform to node.js convention of accepting a callback as last argument and calling that callback with error as the first argument and success value on the second argument.
 *
 * @param {Function} nodeFunction
 * @returns {Function}
 */
module.exports = function promisify(nodeFunction) {
    return function(...args) {
        return new Promise((resolve, reject) => {
            nodeFunction.call(this, ...args, (err, data) => {
                if(err) {
                    reject(err);
                } else {
                    resolve(data);
                }
            })
        });
    };
};

Node 8+内置了Promisify

请参阅我对生成器方法的其他回答,它可以更快地得到结果。

其他回答

另一个简单而有用的方法

function walkDir(root) {
    const stat = fs.statSync(root);

    if (stat.isDirectory()) {
        const dirs = fs.readdirSync(root).filter(item => !item.startsWith('.'));
        let results = dirs.map(sub => walkDir(`${root}/${sub}`));
        return [].concat(...results);
    } else {
        return root;
    }
}

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。

这就是我的答案。希望它能帮助到一些人。

我的重点是使搜索例程可以停在任何地方,对于找到的文件,告诉原始路径的相对深度。

var _fs = require('fs');
var _path = require('path');
var _defer = process.nextTick;

// next() will pop the first element from an array and return it, together with
// the recursive depth and the container array of the element. i.e. If the first
// element is an array, it'll be dug into recursively. But if the first element is
// an empty array, it'll be simply popped and ignored.
// e.g. If the original array is [1,[2],3], next() will return [1,0,[[2],3]], and
// the array becomes [[2],3]. If the array is [[[],[1,2],3],4], next() will return
// [1,2,[2]], and the array becomes [[[2],3],4].
// There is an infinity loop `while(true) {...}`, because I optimized the code to
// make it a non-recursive version.
var next = function(c) {
    var a = c;
    var n = 0;
    while (true) {
        if (a.length == 0) return null;
        var x = a[0];
        if (x.constructor == Array) {
            if (x.length > 0) {
                a = x;
                ++n;
            } else {
                a.shift();
                a = c;
                n = 0;
            }
        } else {
            a.shift();
            return [x, n, a];
        }
    }
}

// cb is the callback function, it have four arguments:
//    1) an error object if any exception happens;
//    2) a path name, may be a directory or a file;
//    3) a flag, `true` means directory, and `false` means file;
//    4) a zero-based number indicates the depth relative to the original path.
// cb should return a state value to tell whether the searching routine should
// continue: `true` means it should continue; `false` means it should stop here;
// but for a directory, there is a third state `null`, means it should do not
// dig into the directory and continue searching the next file.
var ls = function(path, cb) {
    // use `_path.resolve()` to correctly handle '.' and '..'.
    var c = [ _path.resolve(path) ];
    var f = function() {
        var p = next(c);
        p && s(p);
    };
    var s = function(p) {
        _fs.stat(p[0], function(err, ss) {
            if (err) {
                // use `_defer()` to turn a recursive call into a non-recursive call.
                cb(err, p[0], null, p[1]) && _defer(f);
            } else if (ss.isDirectory()) {
                var y = cb(null, p[0], true, p[1]);
                if (y) r(p);
                else if (y == null) _defer(f);
            } else {
                cb(null, p[0], false, p[1]) && _defer(f);
            }
        });
    };
    var r = function(p) {
        _fs.readdir(p[0], function(err, files) {
            if (err) {
                cb(err, p[0], true, p[1]) && _defer(f);
            } else {
                // not use `Array.prototype.map()` because we can make each change on site.
                for (var i = 0; i < files.length; i++) {
                    files[i] = _path.join(p[0], files[i]);
                }
                p[2].unshift(files);
                _defer(f);
            }
        });
    }
    _defer(f);
};

var printfile = function(err, file, isdir, n) {
    if (err) {
        console.log('-->   ' + ('[' + n + '] ') + file + ': ' + err);
        return true;
    } else {
        console.log('... ' + ('[' + n + '] ') + (isdir ? 'D' : 'F') + ' ' + file);
        return true;
    }
};

var path = process.argv[2];
ls(path, printfile);

我必须将基于promise的砂光器库添加到列表中。

 var sander = require('sander');
 sander.lsr(directory).then( filenames => { console.log(filenames) } );

这是另一个实现。上述解决方案都没有任何限制,因此如果您的目录结构很大,它们都会崩溃并最终耗尽资源。

var async = require('async');
var fs = require('fs');
var resolve = require('path').resolve;

var scan = function(path, concurrency, callback) {
    var list = [];

    var walker = async.queue(function(path, callback) {
        fs.stat(path, function(err, stats) {
            if (err) {
                return callback(err);
            } else {
                if (stats.isDirectory()) {
                    fs.readdir(path, function(err, files) {
                        if (err) {
                            callback(err);
                        } else {
                            for (var i = 0; i < files.length; i++) {
                                walker.push(resolve(path, files[i]));
                            }
                            callback();
                        }
                    });
                } else {
                    list.push(path);
                    callback();
                }
            }
        });
    }, concurrency);

    walker.push(path);

    walker.drain = function() {
        callback(list);
    }
};

使用50的并发工作得非常好,并且几乎和小型目录结构的简单实现一样快。