I was hoping this would be a simple thing, but I cannot find anything out there to do so.
I just want to get all folders/directories within a given folder/directory.
So for example:
<MyFolder>
|- SomeFolder
|- SomeOtherFolder
|- SomeFile.txt
|- SomeOtherFile.txt
|- x-directory
I would expect to get an array of:
["SomeFolder", "SomeOtherFolder", "x-directory"]
Or the above with the path if that was how it was served...
So does anything already exist to do the above?
Promise
import { readdir } from 'fs/promises'
const getDirectories = async source =>
(await readdir(source, { withFileTypes: true }))
.filter(dirent => dirent.isDirectory())
.map(dirent => dirent.name)
Callback
import { readdir } from 'fs'
const getDirectories = (source, callback) =>
readdir(source, { withFileTypes: true }, (err, files) => {
if (err) {
callback(err)
} else {
callback(
files
.filter(dirent => dirent.isDirectory())
.map(dirent => dirent.name)
)
}
})
Syncronous
import { readdirSync } from 'fs'
const getDirectories = source =>
readdirSync(source, { withFileTypes: true })
.filter(dirent => dirent.isDirectory())
.map(dirent => dirent.name)
List directories using a path.
function getDirectories(path) {
return fs.readdirSync(path).filter(function (file) {
return fs.statSync(path+'/'+file).isDirectory();
});
}
Recursive solution
I came here in search of a way to get all of the subdirectories, and all of their subdirectories, etc. Building on the accepted answer, I wrote this:
const fs = require('fs');
const path = require('path');
function flatten(lists) {
return lists.reduce((a, b) => a.concat(b), []);
}
function getDirectories(srcpath) {
return fs.readdirSync(srcpath)
.map(file => path.join(srcpath, file))
.filter(path => fs.statSync(path).isDirectory());
}
function getDirectoriesRecursive(srcpath) {
return [srcpath, ...flatten(getDirectories(srcpath).map(getDirectoriesRecursive))];
}
This should do it:
CoffeeScript (sync)
fs = require 'fs'
getDirs = (rootDir) ->
files = fs.readdirSync(rootDir)
dirs = []
for file in files
if file[0] != '.'
filePath = "#{rootDir}/#{file}"
stat = fs.statSync(filePath)
if stat.isDirectory()
dirs.push(file)
return dirs
CoffeeScript (async)
fs = require 'fs'
getDirs = (rootDir, cb) ->
fs.readdir rootDir, (err, files) ->
dirs = []
for file, index in files
if file[0] != '.'
filePath = "#{rootDir}/#{file}"
fs.stat filePath, (err, stat) ->
if stat.isDirectory()
dirs.push(file)
if files.length == (index + 1)
cb(dirs)
JavaScript (async)
var fs = require('fs');
var getDirs = function(rootDir, cb) {
fs.readdir(rootDir, function(err, files) {
var dirs = [];
for (var index = 0; index < files.length; ++index) {
var file = files[index];
if (file[0] !== '.') {
var filePath = rootDir + '/' + file;
fs.stat(filePath, function(err, stat) {
if (stat.isDirectory()) {
dirs.push(this.file);
}
if (files.length === (this.index + 1)) {
return cb(dirs);
}
}.bind({index: index, file: file}));
}
}
});
}
Alternatively, if you are able to use external libraries, you can use filehound. It supports callbacks, promises and sync calls.
Using promises:
const Filehound = require('filehound');
Filehound.create()
.path("MyFolder")
.directory() // only search for directories
.find()
.then((subdirectories) => {
console.log(subdirectories);
});
Using callbacks:
const Filehound = require('filehound');
Filehound.create()
.path("MyFolder")
.directory()
.find((err, subdirectories) => {
if (err) return console.error(err);
console.log(subdirectories);
});
Sync call:
const Filehound = require('filehound');
const subdirectories = Filehound.create()
.path("MyFolder")
.directory()
.findSync();
console.log(subdirectories);
For further information (and examples), check out the docs: https://github.com/nspragg/filehound
Disclaimer: I'm the author.
With node.js version >= v10.13.0, fs.readdirSync will return an array of fs.Dirent objects if withFileTypes option is set to true.
So you can use,
const fs = require('fs')
const directories = source => fs.readdirSync(source, {
withFileTypes: true
}).reduce((a, c) => {
c.isDirectory() && a.push(c.name)
return a
}, [])
var getDirectories = (rootdir , cb) => {
fs.readdir(rootdir, (err, files) => {
if(err) throw err ;
var dirs = files.map(filename => path.join(rootdir,filename)).filter( pathname => fs.statSync(pathname).isDirectory());
return cb(dirs);
})
}
getDirectories( myDirectories => console.log(myDirectories));``
Using fs-extra, which promises the async fs calls, and the new await async syntax:
const fs = require("fs-extra");
async function getDirectories(path){
let filesAndDirectories = await fs.readdir(path);
let directories = [];
await Promise.all(
filesAndDirectories.map(name =>{
return fs.stat(path + name)
.then(stat =>{
if(stat.isDirectory()) directories.push(name)
})
})
);
return directories;
}
let directories = await getDirectories("/")
This answer does not use blocking functions like readdirSync or statSync. It does not use external dependencies nor find itself in the depths of callback hell.
Instead we use modern JavaScript conveniences like Promises and and async-await syntaxes. And asynchronous results are processed in parallel; not sequentially -
const { readdir, stat } =
require ("fs") .promises
const { join } =
require ("path")
const dirs = async (path = ".") =>
(await stat (path)) .isDirectory ()
? Promise
.all
( (await readdir (path))
.map (p => dirs (join (path, p)))
)
.then
( results =>
[] .concat (path, ...results)
)
: []
I'll install an example package, and then test our function -
$ npm install ramda
$ node
Let's see it work -
> dirs (".") .then (console.log, console.error)
[ '.'
, 'node_modules'
, 'node_modules/ramda'
, 'node_modules/ramda/dist'
, 'node_modules/ramda/es'
, 'node_modules/ramda/es/internal'
, 'node_modules/ramda/src'
, 'node_modules/ramda/src/internal'
]
Using a generalised module, Parallel, we can simplify the definition of dirs -
const Parallel =
require ("./Parallel")
const dirs = async (path = ".") =>
(await stat (path)) .isDirectory ()
? Parallel (readdir (path))
.flatMap (f => dirs (join (path, f)))
.then (results => [ path, ...results ])
: []
The Parallel module used above was a pattern that was extracted from a set of functions designed to solve a similar problem. For more explanation, see this related Q&A.
And a async version of getDirectories, you need the async module for this:
var fs = require('fs');
var path = require('path');
var async = require('async'); // https://github.com/caolan/async
// Original function
function getDirsSync(srcpath) {
return fs.readdirSync(srcpath).filter(function(file) {
return fs.statSync(path.join(srcpath, file)).isDirectory();
});
}
function getDirs(srcpath, cb) {
fs.readdir(srcpath, function (err, files) {
if(err) {
console.error(err);
return cb([]);
}
var iterator = function (file, cb) {
fs.stat(path.join(srcpath, file), function (err, stats) {
if(err) {
console.error(err);
return cb(false);
}
cb(stats.isDirectory());
})
}
async.filter(files, iterator, cb);
});
}
Fully async version with ES6, only native packages, fs.promises and async/await, does file operations in parallel:
const fs = require('fs');
const path = require('path');
async function listDirectories(rootPath) {
const fileNames = await fs.promises.readdir(rootPath);
const filePaths = fileNames.map(fileName => path.join(rootPath, fileName));
const filePathsAndIsDirectoryFlagsPromises = filePaths.map(async filePath => ({path: filePath, isDirectory: (await fs.promises.stat(filePath)).isDirectory()}))
const filePathsAndIsDirectoryFlags = await Promise.all(filePathsAndIsDirectoryFlagsPromises);
return filePathsAndIsDirectoryFlags.filter(filePathAndIsDirectoryFlag => filePathAndIsDirectoryFlag.isDirectory)
.map(filePathAndIsDirectoryFlag => filePathAndIsDirectoryFlag.path);
}
Tested, it works nicely.
You can use graph-fs
const {Node} = require("graph-fs");
const directory = new Node("/path/to/directory");
const subDirectories = directory.children.filter(child => child.is.directory);
Using the glob package, just add a trailing slash to find directories only:
import {promise as glob} from "glob-promise"
const firstLevelFolders = await glob("MyFolder/*/")
const recursiveFolders = await glob("MyFolder/**/")
CoffeeScript version of this answer, with proper error handling:
fs = require "fs"
{join} = require "path"
async = require "async"
get_subdirs = (root, callback)->
fs.readdir root, (err, files)->
return callback err if err
subdirs = []
async.each files,
(file, callback)->
fs.stat join(root, file), (err, stats)->
return callback err if err
subdirs.push file if stats.isDirectory()
callback null
(err)->
return callback err if err
callback null, subdirs
Depends on async
Alternatively, use a module for this!
(There are modules for everything. [citation needed])
If you need to use all async version. You can have something like this.
Record the directory length, uses it as an indicator to tell if all async stat tasks are finished.
If the async stat tasks are finished, all the file stat has been checked, so call the callback
This will only work as long as Node.js is single thread, because it assumes no two async tasks will increase the counter at the same time.
'use strict';
var fs = require("fs");
var path = require("path");
var basePath = "./";
function result_callback(results) {
results.forEach((obj) => {
console.log("isFile: " + obj.fileName);
console.log("fileName: " + obj.isFile);
});
};
fs.readdir(basePath, (err, files) => {
var results = [];
var total = files.length;
var finished = 0;
files.forEach((fileName) => {
// console.log(fileName);
var fullPath = path.join(basePath, fileName);
fs.stat(fullPath, (err, stat) => {
// this will work because Node.js is single thread
// therefore, the counter will not increment at the same time by two callback
finished++;
if (stat.isFile()) {
results.push({
fileName: fileName,
isFile: stat.isFile()
});
}
if (finished == total) {
result_callback(results);
}
});
});
});
As you can see, this is a "depth first" approach, and this could result in callback hell, and it is not quite "functional" . People try to solve this problem with Promise, by wrapping the async task into an Promise object.
'use strict';
var fs = require("fs");
var path = require("path");
var basePath = "./";
function result_callback(results) {
results.forEach((obj) => {
console.log("isFile: " + obj.fileName);
console.log("fileName: " + obj.isFile);
});
};
fs.readdir(basePath, (err, files) => {
var results = [];
var total = files.length;
var finished = 0;
var promises = files.map((fileName) => {
// console.log(fileName);
var fullPath = path.join(basePath, fileName);
return new Promise((resolve, reject) => {
// try to replace fullPath wil "aaa", it will reject
fs.stat(fullPath, (err, stat) => {
if (err) {
reject(err);
return;
}
var obj = {
fileName: fileName,
isFile: stat.isFile()
};
resolve(obj);
});
});
});
Promise.all(promises).then((values) => {
console.log("All the promise resolved");
console.log(values);
console.log("Filter out folder: ");
values
.filter((obj) => obj.isFile)
.forEach((obj) => {
console.log(obj.fileName);
});
}, (reason) => {
console.log("Not all the promise resolved");
console.log(reason);
});
});
use fs、path module can got the folder. this use Promise. If your will get the fill, your can change isDirectory() to isFile() Nodejs--fs--fs.Stats.At last, you can get the file'name file'extname and so on Nodejs---Path
var fs = require("fs"),
path = require("path");
//your <MyFolder> path
var p = "MyFolder"
fs.readdir(p, function (err, files) {
if (err) {
throw err;
}
//this can get all folder and file under <MyFolder>
files.map(function (file) {
//return file or folder path, such as **MyFolder/SomeFile.txt**
return path.join(p, file);
}).filter(function (file) {
//use sync judge method. The file will add next files array if the file is directory, or not.
return fs.statSync(file).isDirectory();
}).forEach(function (files) {
//The files is array, so each. files is the folder name. can handle the folder.
console.log("%s", files);
});
});
Just in case anyone else ends up here from a web search, and has Grunt already in their dependency list, the answer to this becomes trivial. Here's my solution:
/**
* Return all the subfolders of this path
* #param {String} parentFolderPath - valid folder path
* #param {String} glob ['/*'] - optional glob so you can do recursive if you want
* #returns {String[]} subfolder paths
*/
getSubfolders = (parentFolderPath, glob = '/*') => {
return grunt.file.expand({filter: 'isDirectory'}, parentFolderPath + glob);
}
Another recursive approach
Thanks to Mayur for knowing me about withFileTypes. I written following code for getting files of particular folder recursively. It can be easily modified to get only directories.
const getFiles = (dir, base = '') => readdirSync(dir, {withFileTypes: true}).reduce((files, file) => {
const filePath = path.join(dir, file.name)
const relativePath = path.join(base, file.name)
if(file.isDirectory()) {
return files.concat(getFiles(filePath, relativePath))
} else if(file.isFile()) {
file.__fullPath = filePath
file.__relateivePath = relativePath
return files.concat(file)
}
}, [])
functional programming
const fs = require('fs')
const path = require('path')
const R = require('ramda')
const getDirectories = pathName => {
const isDirectory = pathName => fs.lstatSync(pathName).isDirectory()
const mapDirectories = pathName => R.map(name => path.join(pathName, name), fs.readdirSync(pathName))
const filterDirectories = listPaths => R.filter(isDirectory, listPaths)
return {
paths:R.pipe(mapDirectories)(pathName),
pathsFiltered: R.pipe(mapDirectories, filterDirectories)(pathName)
}
}
You could use dree, if using a module is affordable
const dree = require('dree');
const options = {
depth: 1
};
const fileCallback = function() {};
const directories = [];
const dirCallback = function(dir) {
directories.push(dir.name);
};
dree.scan('./dir', {});
console.log(directories);
The directories which are directed children of the specified path ("./dir") will be printed.
If you do not put the option depth: 1, you would even obtain all the directories in a recursively way, so not only the directed children of the specified path.
I am making a program that will read content of files inside nested folders.For now I am just trying to log the content of the file in console. But I am getting two logs instead of only one.Here is what I have done till now
const fs = require('fs');
const path = require('path');
const { promisify } = require('util');
const getStats = promisify(fs.stat);
const readdir = promisify(fs.readdir);
const http = require('http');
handle_files = async (req, res) => {
let files = await scanDir("logs_of_109");
let result = await read_content(files)
check_file_content(result)
res.writeHead(200, { 'Content-Type': 'text/html' });
// console.log(result)
res.write("Hello");
res.end();
};
check_file_content = (file_data) => {
console.log(file_data[1])
}
async function read_content(files) {
let file_data = []
files.map(file => {
let start_index = file.toString().lastIndexOf('.') + 1
let ext = file.substring(start_index, file.length)
if (ext == 'data') {
file_data.push(fs.readFileSync(file, { encoding: 'utf-8' }))
}
})
return file_data
}
http.createServer(handle_files).listen(8080)
async function scanDir(dir, fileList = []) {
// fetch list of files from the giver directory
let files = await readdir(dir);
// loop through all the files
for (let file of files) {
// join new folder name after the parent folder
// logs_of_109/24
let filePath = path.join(dir, file);
try {
//
let stats = await getStats(filePath);
if (!stats.isDirectory()) {
// add the filepath to the array
fileList.push(filePath);
}
if (stats.isDirectory()) {
await scanDir(filePath, fileList);
}
} catch (err) {
// Drop on the floor..
}
}
return fileList;
}
I expect the file content to be logged only once but it is logging twice on my console. Why is this happening and how do I stop this?
Your browser is making two requests to your server, most likely one for the URL you put in the address bar and another for favicon.ico. (You can quickly tell by opening the dev tools on your browser and going to the Network tab.)
handleFiles should look at req (specifically its url property) and act according to what's being requested. (This is something the code should be doing anyway.)
Side note 1: You're passing an async function into something (createServer) that won't do anything with the promise it returns. If you do that, it's important to catch any errors in the function locally within the function, since (again) nothing else is going to handle them. E.g.:
handle_files = async (req, res) => {
try {
let files = await scanDir("logs_of_109");
let result = await read_content(files)
check_file_content(result)
res.writeHead(200, { 'Content-Type': 'text/html' });
// console.log(result)
res.write("Hello");
res.end();
} catch (e) {
// ...handle error here...
}
};
Side note 2: That code is falling prey to The Horror of Implicit Globals¹. Declare your variables in the appropriate scope. Not declaring them, in loose mode, makes them globals. (Also recommend using strict mode, so you get an error for this.)
¹ (that's a post on my anemic little blog)
The answer above is correct.
My approach is to solve it via 'routing' of any kind.
Here is small basic example of how it can be done
const fs = require('fs');
const path = require('path');
const { promisify } = require('util');
const getStats = promisify(fs.stat);
const readdir = promisify(fs.readdir);
const http = require('http');
handle_routes = async (req, res) => {
switch(req.url) {
case '/files':
handle_files(req, res);
default:
console.log('for default page');
}
}
handle_files = async (req, res) => {
let files = await scanDir("logs_of_109");
let result = await read_content(files)
check_file_content(result)
res.writeHead(200, { 'Content-Type': 'text/html' });
res.write("Hello");
res.end();
};
check_file_content = (file_data) => {
console.log(file_data[1])
}
async function read_content(files) {
let file_data = []
files.map(file => {
let start_index = file.toString().lastIndexOf('.') + 1
let ext = file.substring(start_index, file.length)
if (ext == 'data') {
file_data.push(fs.readFileSync(file, { encoding: 'utf-8' }))
}
})
return file_data
}
http.createServer(handle_routes).listen(8080)
async function scanDir(dir, fileList = []) {
// fetch list of files from the giver directory
let files = await readdir(dir);
// loop through all the files
for (let file of files) {
// join new folder name after the parent folder
// logs_of_109/24
let filePath = path.join(dir, file);
try {
//
let stats = await getStats(filePath);
if (!stats.isDirectory()) {
// add the filepath to the array
fileList.push(filePath);
}
if (stats.isDirectory()) {
await scanDir(filePath, fileList);
}
} catch (err) {
// Drop on the floor..
}
}
return fileList;
}
This gives you possibility to call handle_files function by going to localhost:8080/files url
I'm using node.js and trying to read 3 xlsx files at the same time and only when all the 3 files whas readen and the callback executed, return all of them in a array.
I try to use Promise.all but I'm getting the array before the callbacks are done.
Here is the code
const path = require('path');
const extractor = require("xlsx-to-json");
(async () =>{
let x = [];
const dir = 'my/path';
const files = [
{ name:'File1.xlsx'},
{ name:'File2.xlsx' },
{ name:'File3.xlsx'}
];
await Promise.all(
files.map(async (file)=>{
console.log('init: %s',file.name);
let start = new Date();
let filePath = path.resolve(dir,file.name);
extractor({
input: filePath,
output: null
}, function(err, result) {
if(err) {
console.error(err);
} else {
x.push(result);
let end = new Date() - start;
console.info('Extraction time of [%s]: %dms', file.name, end);
}
});
})
);
console.log(x);
})();
The output I need is:
init: File1.xlsx
init: File2.xlsx
init: File3.xlsx
Extraction time of [File1.xlsx]: 17233ms
Extraction time of [File2.xlsx]: 16615ms
Extraction time of [File3.xlsx]: 15266ms
[ some json objects ]
But I get the following:
init: File1.xlsx
init: File2.xlsx
init: File3.xlsx
[] //empty array
Extraction time of [File1.xlsx]: 17233ms
Extraction time of [File2.xlsx]: 16615ms
Extraction time of [File3.xlsx]: 15266ms
Using Promise.all was on the righ track, but you didn't use it correctly.
Please see inline comment below
const path = require('path');
const extractor = require("xlsx-to-json");
(async () => {
//let x = [];
const dir = 'my/path';
const files = [
{ name: 'File1.xlsx' },
{ name: 'File2.xlsx' },
{ name: 'File3.xlsx' }
];
// all 3 extracted results will be returned from `await Promise.all()`
let x = await Promise.all(
// `async` not needed here
files.map(/*async*/ (file) => {
console.log('init: %s', file.name);
let start = new Date();
let filePath = path.resolve(dir, file.name);
// Promise wrapper
return new Promise((resolve, reject) => {
extractor({
input: filePath,
output: null
}, function (err, result) {
if (err) {
console.error(err);
// return error by rejecting the Promise
reject(err);
} else {
// x.push(result);
// return result by resolving the Promise
resolve(result);
let end = new Date() - start;
console.info('Extraction time of [%s]: %dms', file.name, end);
}
});
});
})
);
console.log(x);
})();
Here's the util.promisify() version of what I suggested earlier in the comment:
const path = require('path');
const extractor = require("xlsx-to-json");
const util = require('util');
const extractorP = util.promisify(extractor);
const dir = 'my/path';
const files = [
{ name:'File1.xlsx'},
{ name:'File2.xlsx' },
{ name:'File3.xlsx'}
];
Promise.all(
files.map((file) => {
console.log('init: %s',file.name);
let start = new Date();
let filePath = path.resolve(dir,file.name);
// return promise from files.map() callback so we get
// an array of promises
return extractorP({
input: filePath,
output: null
}).then(result => {
let end = new Date() - start;
console.info('Extraction time of [%s]: %dms', file.name, end);
return result;
}).catch(err => {
console.error(err);
throw err;
});
});
).then(results => {
console.log(results);
}).catch(err => {
// put error handling here
});
I think it's always cleaner to promisify outside the implementation and then have an implementation that only uses promises. The whole logic flow just seems cleaner if there's no mix of promises and regular callbacks and, of course, if you use this function anywhere else, you can use the promisified version elsewhere too.
Inside a function, I would like to set the value of a variable (foldersInDir) to the results of getting the contents of a directory using fs.readdir();
I thought using await would force the console.log line to wait for a response, but it's not.
How can I set foldersInDir = the return value?
/*Begin function*/
const listContents = async (myPath) => {
var fs = require('fs');
let foldersInDir = await fs.readdir(myPath, function(err, items) {
console.log(items); //works
return items;
});
console.log(foldersInDir); //does not work, undefined
}
You need to convert readdir to a promise, e.g.:
const foldersPromised = (path) =>
new Promise((resolve, reject) =>
fs.readdir(path, (err, items) =>
err !== undefined ? reject(err) : resolve(items)
)
);
try {
let foldersInDir = await foldersPromised(myPath);
} catch(err) {
console.log(err);
}
const fs = require('fs');
const test = () => {
let folders = fs.readdirSync('.');
return folders;
}
console.log(test());
Edit: sorry, need to promisify() the function
const fs = require('fs');
const { promisify } = require('util') // available in node v8 onwards
const readdir = promisify(fs.readdir)
async function listContents() {
try { // wrap in try-catch in lieu of .then().catch() syntax
const foldersInDir = await readdir(myPath) // call promised function
console.log('OK, folders:', foldersInDir) // success
} catch (e) {
console.log('FAIL reading dir:', e) // fail
}
}
listContents('path/to/folder') // run test
I recommend using the promisify function provided by Node.js to fix the problem. This function will convert a callback-based function to a promise-based function, which can then be used using the await keyword.
const fs = require('fs');
const {
promisify
} = require('util');
const readdirAsync = promisify(fs.readdir);
/*Begin function*/
const listContents = async(myPath) => {
let foldersInDir = await readdirAsync(myPath);
console.log(foldersInDir);
}