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
香草ES6 +异步/等待+小和可读
我没有在这篇文章中找到我想要的答案;在不同的答案中有一些相似的元素,但我只想要一些简单易读的东西。
为了防止它在未来帮助到任何人(比如几个月后的我自己),这就是我最终使用的:
const { readdir } = require('fs/promises');
const { join } = require('path');
const readdirRecursive = async dir => {
const files = await readdir( dir, { withFileTypes: true } );
const paths = files.map( async file => {
const path = join( dir, file.name );
if ( file.isDirectory() ) return await readdirRecursive( path );
return path;
} );
return ( await Promise.all( paths ) ).flat( Infinity );
}
module.exports = {
readdirRecursive,
}
其他回答
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);
}
}
})
});
});
}
对于Node 10.3+,这里是一个For -await解决方案:
#!/usr/bin/env node
const FS = require('fs');
const Util = require('util');
const readDir = Util.promisify(FS.readdir);
const Path = require('path');
async function* readDirR(path) {
const entries = await readDir(path,{withFileTypes:true});
for(let entry of entries) {
const fullPath = Path.join(path,entry.name);
if(entry.isDirectory()) {
yield* readDirR(fullPath);
} else {
yield fullPath;
}
}
}
async function main() {
const start = process.hrtime.bigint();
for await(const file of readDirR('/mnt/home/media/Unsorted')) {
console.log(file);
}
console.log((process.hrtime.bigint()-start)/1000000n);
}
main().catch(err => {
console.error(err);
});
这种解决方案的好处是,您可以立即开始处理结果;例如,读取媒体目录中的所有文件需要12秒,但如果我这样做,我可以在几毫秒内得到第一个结果。
香草ES6 +异步/等待+小和可读
我没有在这篇文章中找到我想要的答案;在不同的答案中有一些相似的元素,但我只想要一些简单易读的东西。
为了防止它在未来帮助到任何人(比如几个月后的我自己),这就是我最终使用的:
const { readdir } = require('fs/promises');
const { join } = require('path');
const readdirRecursive = async dir => {
const files = await readdir( dir, { withFileTypes: true } );
const paths = files.map( async file => {
const path = join( dir, file.name );
if ( file.isDirectory() ) return await readdirRecursive( path );
return path;
} );
return ( await Promise.all( paths ) ).flat( Infinity );
}
module.exports = {
readdirRecursive,
}
现代基于promise的读dir递归版本:
const fs = require('fs');
const path = require('path');
const readDirRecursive = async (filePath) => {
const dir = await fs.promises.readdir(filePath);
const files = await Promise.all(dir.map(async relativePath => {
const absolutePath = path.join(filePath, relativePath);
const stat = await fs.promises.lstat(absolutePath);
return stat.isDirectory() ? readDirRecursive(absolutePath) : absolutePath;
}));
return files.flat();
}
为了好玩,这里有一个基于流的版本,它与highland.js streams库一起工作。作者之一是维克多·伍。
###
directory >---m------> dirFilesStream >---------o----> out
| |
| |
+--------< returnPipe <-----------+
legend: (m)erge (o)bserve
+ directory has the initial file
+ dirListStream does a directory listing
+ out prints out the full path of the file
+ returnPipe runs stat and filters on directories
###
_ = require('highland')
fs = require('fs')
fsPath = require('path')
directory = _(['someDirectory'])
mergePoint = _()
dirFilesStream = mergePoint.merge().flatMap((parentPath) ->
_.wrapCallback(fs.readdir)(parentPath).sequence().map (path) ->
fsPath.join parentPath, path
)
out = dirFilesStream
# Create the return pipe
returnPipe = dirFilesStream.observe().flatFilter((path) ->
_.wrapCallback(fs.stat)(path).map (v) ->
v.isDirectory()
)
# Connect up the merge point now that we have all of our streams.
mergePoint.write directory
mergePoint.write returnPipe
mergePoint.end()
# Release backpressure. This will print files as they are discovered
out.each H.log
# Another way would be to queue them all up and then print them all out at once.
# out.toArray((files)-> console.log(files))