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']
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
因为每个人都应该写自己的,所以我写了一个。
步行(dir, cb, endCb) cb(文件) 零endCb (err |)
脏
module.exports = walk;
function walk(dir, cb, endCb) {
var fs = require('fs');
var path = require('path');
fs.readdir(dir, function(err, files) {
if (err) {
return endCb(err);
}
var pending = files.length;
if (pending === 0) {
endCb(null);
}
files.forEach(function(file) {
fs.stat(path.join(dir, file), function(err, stats) {
if (err) {
return endCb(err)
}
if (stats.isDirectory()) {
walk(path.join(dir, file), cb, function() {
pending--;
if (pending === 0) {
endCb(null);
}
});
} else {
cb(path.join(dir, file));
pending--;
if (pending === 0) {
endCb(null);
}
}
})
});
});
}
其他回答
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。
a .看一下文件模块。它有一个叫walk的函数:
文件。步行(开始,回调) 导航文件树,为每个目录调用回调,传入 (null, dirPath, dirs, files)。
这可能是为你准备的!是的,它是异步的。但是,如果需要的话,我认为您必须自己聚合完整的路径。
B.另一种选择,甚至是我的最爱之一:使用unix find来查找。为什么要再做一件已经编程好的事情呢?也许不是你真正需要的,但仍然值得一试:
var execFile = require('child_process').execFile;
execFile('find', [ 'somepath/' ], function(err, stdout, stderr) {
var file_list = stdout.split('\n');
/* now you've got a list with full path file names */
});
Find有一个很好的内置缓存机制,使得后续搜索非常快,只要只有少数文件夹被更改。
另一个答案,但这次使用的是TypeScript:
/** * Recursively walk a directory asynchronously and obtain all file names (with full path). * * @param dir Folder name you want to recursively process * @param done Callback function, returns all files with full path. * @param filter Optional filter to specify which files to include, * e.g. for json files: (f: string) => /.json$/.test(f) */ const walk = ( dir: string, done: (err: Error | null, results ? : string[]) => void, filter ? : (f: string) => boolean ) => { let results: string[] = []; fs.readdir(dir, (err: Error, list: string[]) => { if (err) { return done(err); } let pending = list.length; if (!pending) { return done(null, results); } list.forEach((file: string) => { file = path.resolve(dir, file); fs.stat(file, (err2, stat) => { if (stat && stat.isDirectory()) { walk(file, (err3, res) => { if (res) { results = results.concat(res); } if (!--pending) { done(null, results); } }, filter); } else { if (typeof filter === 'undefined' || (filter && filter(file))) { results.push(file); } if (!--pending) { done(null, results); } } }); }); }); };
简单,基于异步承诺
const fs = require('fs/promises');
const getDirRecursive = async (dir) => {
try {
const items = await fs.readdir(dir);
let files = [];
for (const item of items) {
if ((await fs.lstat(`${dir}/${item}`)).isDirectory()) files = [...files, ...(await getDirRecursive(`${dir}/${item}`))];
else files.push({file: item, path: `${dir}/${item}`, parents: dir.split("/")});
}
return files;
} catch (e) {
return e
}
};
用法:await getDirRecursive("./public");
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) } );