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Q&A Check if a file exists in Node.js

You can use existsSync: import { existsSync } from 'node:fs'; if (existsSync('/path/to/file')) { console.log('Found'); } else { console.log('Not found'); } If you want to avoid block...

posted 6mo ago by philipp.classen‭ · edited 6mo ago by philipp.classen‭

Answer

#4: Post edited by

philipp.classen‭ · 2024-05-19T00:41:38Z (6 months ago)

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You can use [`existsSync`](https://nodejs.org/api/fs.html#fsexistssyncpath):
```
import { existsSync } from 'node:fs';
if (existsSync('/path/to/file')) {
console.log('Found');
} else {
console.log('Not found');
}
```
If you want to avoid blocking, you can also use [`access`](https://nodejs.org/api/fs.html#fspromisesaccesspath-mode). If you pass no arguments, it runs in `fs.constants.F_OK` mode, which will test if the given file or directory is visible to the calling process:
```
import { access } from 'node:fs/promises';
try {
await access('/path/to/file');
console.log('Found');
} catch {
console.error('Not found');
}
~~```~~

You can use [`existsSync`](https://nodejs.org/api/fs.html#fsexistssyncpath):
```
import { existsSync } from 'node:fs';
if (existsSync('/path/to/file')) {
console.log('Found');
} else {
console.log('Not found');
}
```
If you want to avoid blocking, you can also use [`access`](https://nodejs.org/api/fs.html#fspromisesaccesspath-mode). If you pass no arguments, it runs in `fs.constants.F_OK` mode, which will test if the given file or directory is visible to the calling process:
```
import { access } from 'node:fs/promises';
try {
await access('/path/to/file');
console.log('Found');
} catch {
console.error('Not found');
}
```
Keep in mind that testing if a file exist and then opening it, is not recommended. Instead directly opening the file and handling errors is preferred ([quoting the docs](https://nodejs.org/api/fs.html#fspromisesaccesspath-mode)):
> Using fsPromises.access() to check for the accessibility of a file before calling fsPromises.open() is not recommended. Doing so introduces a race condition, since other processes may change the file's state between the two calls. Instead, user code should open/read/write the file directly and handle the error raised if the file is not accessible.

#3: Post edited by

philipp.classen‭ · 2024-05-19T00:32:13Z (6 months ago)

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You can use [`existsSync`](https://nodejs.org/api/fs.html#fsexistssyncpath):
```
import { existsSync } from 'node:fs';
if (existsSync('/path/to/file')) {
console.log('Found');
} else {
console.log('Not found');
}
```
If you want to avoid blocking, you can also use [`access`](https://nodejs.org/api/fs.html#fspromisesaccesspath-mode). If you pass no arguments, it runs in `fs.constants.F_OK` mode, which will test if the given file or directory is visible to the calling process:
```
import { access } from 'node:fs/promises';
try {
~~await access('/etc/passwd');~~
console.log('Found');
} catch {
console.error('Not found');
}
```

You can use [`existsSync`](https://nodejs.org/api/fs.html#fsexistssyncpath):
```
import { existsSync } from 'node:fs';
if (existsSync('/path/to/file')) {
console.log('Found');
} else {
console.log('Not found');
}
```
If you want to avoid blocking, you can also use [`access`](https://nodejs.org/api/fs.html#fspromisesaccesspath-mode). If you pass no arguments, it runs in `fs.constants.F_OK` mode, which will test if the given file or directory is visible to the calling process:
```
import { access } from 'node:fs/promises';
try {
await access('/path/to/file');
console.log('Found');
} catch {
console.error('Not found');
}
```

#2: Post edited by

philipp.classen‭ · 2024-05-19T00:31:05Z (6 months ago)

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You can use [`existsSync`](https://nodejs.org/api/fs.html#fsexistssyncpath):
```
import { existsSync } from 'node:fs';
if (existsSync('/path/to/file')) {
console.log('Found');
} else {
console.log('Not found');
}
```
If you want to avoid blocking, you can also use [`access`](https://nodejs.org/api/fs.html#fspromisesaccesspath-mode). If you pass no arguments, it runs in `fs.constants.F_OK` mode, which will test if the given file or directory is visible to the calling process:
```
try {
await access('/etc/passwd');
console.log('Found');
} catch {
console.error('Not found');
}
```

You can use [`existsSync`](https://nodejs.org/api/fs.html#fsexistssyncpath):
```
import { existsSync } from 'node:fs';
if (existsSync('/path/to/file')) {
console.log('Found');
} else {
console.log('Not found');
}
```
If you want to avoid blocking, you can also use [`access`](https://nodejs.org/api/fs.html#fspromisesaccesspath-mode). If you pass no arguments, it runs in `fs.constants.F_OK` mode, which will test if the given file or directory is visible to the calling process:
```
import { access } from 'node:fs/promises';
try {
await access('/etc/passwd');
console.log('Found');
} catch {
console.error('Not found');
}
```

#1: Initial revision by

philipp.classen‭ · 2024-05-19T00:28:03Z (6 months ago)

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You can use [`existsSync`](https://nodejs.org/api/fs.html#fsexistssyncpath):

```
import { existsSync } from 'node:fs';

if (existsSync('/path/to/file')) {
  console.log('Found');
} else {
  console.log('Not found');
}
```

If you want to avoid blocking, you can also use [`access`](https://nodejs.org/api/fs.html#fspromisesaccesspath-mode). If you pass no arguments, it runs in `fs.constants.F_OK` mode, which will test if the given file or directory is visible to the calling process:

```
try {
  await access('/etc/passwd');
  console.log('Found');
} catch {
  console.error('Not found');
}
```

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