Node js see if directory exists

In Node. This method works asynchronously to read the contents of the given directory and returns an array of the names of the files in the directory excluding.

Here is an example that reads all files available in a directory and prints their names on the console:. The fs.

The fs module also provides a synchronous variant of readdir called readdirSync that works synchronously and returns an array of the names of the files:. Take a look at this guide to learn more about reading and writing files in a Node.

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To offer you a better browsing experience, we use cookies. By using this site, you agree to our Cookies Policy. How to list all files in a directory with Node. Share Article. Tweet Share Share. Recent Articles. JavaScript, Node.Anyone who has spent any time writing Node has most likely used the file system module.

NodeJS Create Directory

One of the methods in this core module though is not only different from all the others, but according to most experts is not even useful at all, despite its popularity with a host of other developers. Because of this, the method has been deprecated for years now.

I talk, of course, about fs. Furthermore, its main use case scenario, checking whether a file exists before opening, is actually an antipattern and should be replaced by just trying to open the file and possibly handling the error. But despite its long-standing in JS terms at least deprecation, tons of people still continue to use fs.

At least, I myself was when I first ran into this issue. While I agree that the method is often superfluous, and sometimes entirely pointless checking whether a file exists before doing something with that file is not helpful when race conditions may occur and the file may be deleted in the interimI and I am sure many others would argue that there are legitimate use cases for this method, or at least for what this method should have been, had it been designed better.

So if you are looking for a replacement for fs. The official fs documentation recommends using fs. This method checks the accessibility of a file and nothing more or less. It throws an error if the file is not accessible and does absolutely nothing if it is. The code above has a problem: what if myDir exists, but is not a directory but a file which happens to have the same name? The solution is to use fs. Note that it also throws the error in case a different error is encountered. This is actually not necessary because as far as I know, there really are no other possible errors, but hey, you never know!

You need to check for this because unlike what you may expect, checking the stats of an non-existing path will not give you an empty stats object, but rather it will cause the function to fail and throw that error. You might also sometimes see people check for the error number rather than the error code. In async world AKA the real world for us Node peopleyour alternatives to fs.

Here we go. As per the nodeback API, the first and in this case only parameter of fs. Note that I combined checking for the error and the code. An alternative to this particular solution would have been to try to make the dir with fs.

The point of all this is not to get hung up on the details of making a perfect replacement for fs. If you want it, you can keep using it!

Command-line mdn, or how to make a great thing even greater. Please enable JavaScript to view the comments powered by Disqus.By using our site, you acknowledge that you have read and understand our Cookie PolicyPrivacy Policyand our Terms of Service. The dark mode beta is finally here. Change your preferences any time. Stack Overflow for Teams is a private, secure spot for you and your coworkers to find and share information. The answer to this question has changed over the years.

The current answer is here at the top, followed by the various answers over the years in chronological order:.

Sync solution:

You can use fs. Note that fs. The callback parameter to fs. You can use statSync or lstatSync docs linkwhich give you an fs. Stats object. In general, if a synchronous version of a function is available, it will have the same name as the async version with Sync at the end.

node js see if directory exists

So statSync is the synchronous version of stat ; lstatSync is the synchronous version of lstatetc. If you don't care what the entry is and only want to know whether it exists, you can use path. Side note: You've expressly asked how to check synchronouslyso I've used the xyzSync versions of the functions above.

Note how easy it is to call lstat rather than lstatSync :. The below answer from a couple of years ago is now a bit out of date. The current way is to use fs. And here we are in and the Node docs now say that fs. Because the Node folks think it's dumb to check whether something exists before opening it, which it is; but that's not the only reason for checking whether something exists! So we're probably back to the various stat methods Don't know how long it's been there, but there's also fs.

And at least as of Octoberthe fs. But note that the access not being available is considered an errorso this would probably be best if you're expecting the file to be accessible:. Looking at the source, there's a synchronous version of path. Looks like it got missed in the docs. Please use fs. Use fs.

It's not deprecated. You may be able to determine definitively that the file exists or doesn't exist, but you may also get a permissions error. The permissions error doesn't necessarily imply that the file exists, because you could lack permission to the directory containing the file on which you are checking. And of course there is the chance you could encounter some other error in checking for file existence. While the fs. Needing an answer to this question myself I looked up the node docs, seems you should not be using fs.

There should almost never be a reason to use it in your own code. In particular, checking if a file exists before opening it is an anti-pattern that leaves you vulnerable to race conditions: another process may remove the file between the calls to fs. Just open the file and handle the error when it's not there. I use below function to test if file exists. It catches also other exceptions.By using our site, you acknowledge that you have read and understand our Cookie PolicyPrivacy Policyand our Terms of Service.

Code Review Stack Exchange is a question and answer site for peer programmer code reviews. It only takes a minute to sign up. While I'm aware that code with callbacks tends to be complex, I'm wondering if there are any patterns or something to improve my situation.

You can actually omit fs. The fs. You can scavenge through the err object that fs. As I remember, when fs. So essentially, we reduced the number of indents caused by callbacks and also reduced it by restructuring if-else statements.

Sign up to join this community. The best answers are voted up and rise to the top. Home Questions Tags Users Unanswered. Checking if a file exists then do something if it's not a directory Ask Question. Asked 7 years, 2 months ago. Active 1 month ago. Viewed 36k times. Active Oldest Votes. Joseph Joseph Sign up or log in Sign up using Google.

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Sign up using Facebook. Sign up using Email and Password. Post as a guest Name. Email Required, but never shown. The Overflow Blog. The Overflow How many jobs can be done at home? Socializing with co-workers while social distancing. Featured on Meta. Community and Moderator guidelines for escalating issues via new response…. Feedback on Q2 Community Roadmap.The simplest way to check if a file exists in the file system is by using the fs module 's fs.

It returns true if the path exists, false otherwise:. This method is synchronous which means it will block the execution until the operation is completed. If you want to check if the file exists asynchronously, use fs. It is the non-blocking way of checking the file existence without opening it:.

Checking whether a file/directory exists without using fs.exists

In addition to checking the file existence, you can even use fs. Similar to fs. Follow attacomsian on Twitter. Subscribe to RSS Feed. Need help to launch a new product? I am available for contract work. Hire me to accomplish your business goals with engineering and design. Try now. Join the weekly newsletter to improve your coding skills quickly, with easy to follow tutorials and protips every week.

Subscribe to my weekly newsletter to improve your coding skills quickly, with easy to follow tutorials and protips every week. To offer you a better browsing experience, we use cookies. By using this site, you agree to our Cookies Policy. How to check if a file exists in Node.

The default value is fs. Share Article. Tweet Share Share.

node js see if directory exists

Recent Articles. JavaScript, Node.Posted by: admin November 2, Leave a comment. The answer to this question has changed over the years. The current answer is here at the top, followed by the various answers over the years in chronological order:. You can use fs. Note that fs. The callback parameter to fs. You can use statSync or lstatSync docs linkwhich give you an fs.

node js see if directory exists

Stats object. In general, if a synchronous version of a function is available, it will have the same name as the async version with Sync at the end. So statSync is the synchronous version of stat ; lstatSync is the synchronous version of lstatetc.

Note how easy it is to call lstat rather than lstatSync :. The below answer from a couple of years ago is now a bit out of date. The current way is to use fs. And here we are in and the Node docs now say that fs. And at least as of Octoberthe fs. Looks like it got missed in the docs.

Please use fs. Use fs. And of course there is the chance you could encounter some other error in checking for file existence. While the fs. Needing an answer to this question myself I looked up the node docs, seems you should not be using fs. There should almost never be a reason to use it in your own code.

In particular, checking if a file exists before opening it is an anti-pattern that leaves you vulnerable to race conditions: another process may remove the file between the calls to fs. I use below function to test if file exists.

It catches also other exceptions. So in case there are rights issues e. It would be wrong to ignore this kinds of exceptions. Some answers here says that fs. According to the docs this is no more true.I was looking for a way to check if a directory exists and if not, create it. The problem with this method is that it is deprecated! Makes no sense using it. The hint was to use the fs. This function returns surprise the stats of a file system object - whether a directory or a file.

What the documentation failed to mention was - what happened when the file or directory doesn't exist! It only says. Surprisingly or not :fs. So with the async method, one might do something like this assuming fs is already defined, of course :.

This works async. Sadly, I had to use the sync method. The Sync methods don't have any way of notifying about an error. Except for exceptions! As it turns out, the fs. Creating the sync version is as easy as that:.

Of course, you should handle the unexpected exception of problems while creating the directory, just like with any Sync method used. Connect with me on Twitter or LinkedIn to continue the discussion. It only says The callback gets two arguments err, stats where stats is a fs. Stats object. Using is as simple as before: checkDirectorySync ".

And that's it. Rather easy and self explanatory. Just thought someone else might find it useful.


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