I am using angular 6. I want to delete multiple files from backend folder for that, I am using fs.removeSync() but it gives below exception for me.
can someone help me?
"UnhandledPromiseRejectionWarning: TypeError: fs.removeSync is not a
function "
My Code:
fs.removeSync('/NodeWorkspace/uploads/output/*.csv');
Based on node.js documentation removeSync function not exist. For delete file use unlinkSync function like this:
fs.unlinkSync(path)
But I don't think that work for multiple files, you can use glob package:
var glob = require("glob")
// options is optional
glob("/NodeWorkspace/uploads/output/*.csv", options, function (er, files) {
for (const file of files) {
fs.unlinkSync(file);
}
})
Note: Remember for delete directory use fs.rmdir();
fs.removeSync(path) is a function of fs-extra library which is a wrapper over fs provided by nodejs.
Try using fs.unlinkSync(path).
Related
I have a standard webpack environment set up, and I am using ES6 imports with npm packages (the usual import name from 'package'). I'm using webpack-dev-server as my dev environment, and the standard webpack build for building the output directory.
I have a zip file in my source containing a large number of XML files, and in my JS program, I want to be able to read that zip file in and be able to extract individual files from it, so I can get the text from those files and process the XML in them.
I am currently using the xmldoc package for transforming XML text to a JSON object for processing, but I have not been able to find a reliable package for reading in a zip file (using the path to the file) and being able to get the individual files in it. In the ones I have tried, I have run into trouble with node's fs module. If I try adding the target: 'node' property to my webpack config file, I receive an error stating require is not defined.
Is there a reliable npm package compatible with ES6 imports that can read a zip file into my program? I realize that means the zip must be included in the build files to be sent to the browser, but that is better than including the hundreds of individual files without zipping them. Thanks!
I think you want browserfs. Here is example code from the readme. You will also need to do some config for webpack (check the readme):
fetch('mydata.zip').then(function(response) {
return response.arrayBuffer();
}).then(function(zipData) {
var Buffer = BrowserFS.BFSRequire('buffer').Buffer;
BrowserFS.configure({
fs: "MountableFileSystem",
options: {
"/zip": {
fs: "ZipFS",
options: {
// Wrap as Buffer object.
zipData: Buffer.from(zipData)
}
},
"/tmp": { fs: "InMemory" },
"/home": { fs: "IndexedDB" }
}
}, function(e) {
if (e) {
// An error occurred.
throw e;
}
// Otherwise, BrowserFS is ready to use!
});
});
I knew nothing about fs until I was learning to use casperjs to scrape some content from a website and save them to a file. Following some examples on the web, I write this file scrape.js (The json data has been tested so it has nothing to do with the issue):
var fs = require('fs');
var url = "http://w.nycweb.io/index.php?option=com_k2&view=itemlist&id=4&Itemid=209&format=json";
var casper = require('casper').create();
casper.start(url,function(){
var json = JSON.parse(this.fetchText('pre'));
var jsonOfItems={},items = json.items;
items.forEach(function(item){
jsonOfItems[item.id] = item.introtext.split('\n');
})
fs.write('videoLinks.json',JSON.stringify(jsonOfItems),function(err){
if (err) console.log(err);
console.log('videoLinks.json saved');
})
});
casper.run();
When I do casperjs scrape.js in command line of my Ubuntu 14.04 server, I won't see the file saved message as expected, although the file is properly saved. So this is the first question: why the callback isn't running at all?
Secondly, I also tried fs.writeFile, but when I replace fs.write with it, the file isn't saved at all, nor is there any error information.
I do notice that in casper documentation it's said that casper is not a node.js module and some module of node.js won't be available, but I doubt it has anything to do with my issues. And I think it worths to mention that previously when I run this script I only get a respond like
I'm 'fs' module.
I had to follow this question to reinstall fs module globally to get it working.
fs.write expects a file descriptor where you are trying to give it a filename. Try fs.writeFile. https://nodejs.org/dist/latest-v4.x/docs/api/fs.html#fs_fs_writefile_file_data_options_callback
Edit: Oh you tried that. Are you sure it didn't write it somewhere like the root directory? Tried a full path in there?
And what version of node are you running?
I am using node v0.12.5 with nwjs and I have defined my own custom module inside of my project so that I can modularise my project (obviously).
I am trying to call my module from another module in my project but every time I attempt to require it I get the error could not find module 'uploader'.
My uploader module is currently very simple and looks like:
function ping_server(dns, cb) {
require('dns').lookup(dns, function(err) {
if (err && err.code == "ENOTFOUND") {
cb(false);
} else {
cb(true);
}
})
}
function upload_files()
{
}
module.exports.ping_server = ping_server;
module.exports.upload_files = upload_files;
With the idea that it will be used to recursively push files to a requested server if it can be pinged when the test device has internet connection.
I believe I have exported the methods correctly here using the module.exports syntax, I then try to include this module in my test.js file by using:
var uploader = require('uploader');
I also tried
var uploader = require('uploader.js');
But I believe node will automatically look for uploader.js if uploader is specified.
The file hierarchy for my app is as follows:
package.json
public
|-> lib
|-> test.js
|-> uploader.js
|-> css
|-> img
The only thing I am thinking, is that I heard node will try and source the node_modules folder which is to be included at the root directory of the application, could this be what is causing node not to find it? If not, why can node not see my file from test.js given they exist in the same directory?
UPDATE Sorry for the confusion, I have also tried using require('./uploader') and I am still getting the error: Uncaught Error: Cannot find module './uploader'.
UPDATE 2 I am normally completely against using images to convey code problems on SO, but I think this will significantly help the question:
It's clear here that test.js and uploader.js reside in the same location
When you don't pass a path (relative or absolute) to require(), it does a module lookup for the name passed in.
Change your require('uploader') to require('./uploader') or require(__dirname + '/uploader').
To load a local module (ie not one from node_modules) you need to prefix the path with ./. https://nodejs.org/api/modules.html#modules_modules
So in your case it would be var uploader = require('./uploader');
This problem stemmed from using Node Webkit instead of straight Node, as stated in their documentation all modules will be source from a node_modules directory at the root of the project.
Any internal non C++ libraries should be placed in the node_modules directory in order for Node webkit to find them.
Therefore to fix, I simply added a node_modules directory at the root of my project (outside of app and public) and placed the uploader.js file inside of there. Now when I call require('uploader') it works as expected.
If you're developing on a mac, check your file system case sensitivity. It could be that the required filename is capitalized wrong.
I'm trying to upload a file in my node/express app, but everytime I've got the ENOENT error when renaming the file. My code is that:
var tmp_path = req.files.file.path;
fs.rename(tmp_path, target_path, function (err) {
if(err) throw err;
...
});
where target_path will be the destination path. If I do:
console.log('exists ' + fs.existsSync(tmp_path));
then my server logs:
exists true
Also, listing the contents of tmp directory shows that the file is there. What's the problem?
FS methods like fs.rename which create, move or rename files expect that any directories in the path already exist. When they do not, you'll get an ENOENT. Since very often what you mean is "make this file -- and any directories in the path I specify for it" you may want to consider using an NPM library that abstracts access to fs with methods that take care of such things.
There are quite a few options. For example fs-extra is one of the better-tested libraries. Using fs-extra you can use ensureDir in that operation to make the directory structure first if it does not yet exist.
Supervisor is a package for Node.js that monitors files in your app directory for modifications and reloads the app when a modification occurs.
This script interprets symbolic links as regular files and logs out a warning. I would like to fork Supervisor so that either this can be fixed entirely or that a more descriptive warning is produced.
How can I use the File System module of Node.js to determine if a given file is really an symbolic link?
You can use fs.lstat and then call statis.isSymbolicLink() on the fs.Stats object that's passed into your lstat callback.
fs.lstat('myfilename', function(err, stats) {
console.log(stats.isSymbolicLink());
});
Seems like you can use isSymbolicLink()
const files = fs.readdirSync(dir, {encoding: 'utf8', withFileTypes: true});
files.forEach((file) => {
if (file.isSymbolicLink()) {
console.log('found symlink!');
}
}