Filesystem Functions
********************

.[perex]
[api:Nette\Utils\FileSystem] is a class, which contains useful functions for working with a filesystem. One advantage over native PHP functions is that they throw exceptions in case of errors.


If you need to search for files on the disk, use the [Finder |finder].

Installation:

```shell
composer require nette/utils
```

Following examples assume the following class alias is defined:

```php
use Nette\Utils\FileSystem;
```


Manipulation
============


copy(string $origin, string $target, bool $overwrite=true): void .[method]
--------------------------------------------------------------------------

Copies a file or an entire directory. Overwrites existing files and directories by default. If `$overwrite` is set to `false` and a `$target` already exists, throws an exception `Nette\InvalidStateException`. Throws an exception `Nette\IOException` on error occurred.

```php
FileSystem::copy('/path/to/source', '/path/to/dest', overwrite: true);
```


createDir(string $directory, int $mode=0777): void .[method]
------------------------------------------------------------

Creates a directory if it does not exist, including parent directories. Throws an exception `Nette\IOException` on error occurred.

```php
FileSystem::createDir('/path/to/dir');
```


delete(string $path): void .[method]
------------------------------------

Deletes a file or an entire directory if exists. If the directory is not empty, it deletes its contents first. Throws an exception `Nette\IOException` on error occurred.

```php
FileSystem::delete('/path/to/fileOrDir');
```


makeWritable(string $path, int $dirMode=0777, int $fileMode=0666): void .[method]
---------------------------------------------------------------------------------

Sets file permissions to `$fileMode` or directory permissions to `$dirMode`. Recursively traverses and sets permissions on the entire contents of the directory as well.

```php
FileSystem::makeWritable('/path/to/fileOrDir');
```


open(string $path, string $mode): resource .[method]
----------------------------------------------------

Opens file and returns resource. The `$mode` parameter works the same as the native `fopen()`:https://www.php.net/manual/en/function.fopen.php function. If an error occurs, it raises the `Nette\IOException` exception.

```php
$res = FileSystem::open('/path/to/file', 'r');
```


read(string $file): string .[method]
------------------------------------

Reads the content of a `$file`. Throws an exception `Nette\IOException` on error occurred.

```php
$content = FileSystem::read('/path/to/file');
```


readLines(string $file, bool $stripNewLines=true): \Generator .[method]
-----------------------------------------------------------------------

Reads the file content line by line. Unlike the native `file()` function, it does not read the entire file into memory, but reads it continuously, so that files larger than the available memory can be read. The `$stripNewLines` specifies whether to strip the `\r` and `\n` line break characters.
In case of an error, it raises a `Nette\IOException` exception.

```php
$lines = FileSystem::readLines('/path/to/file');

foreach ($lines as $lineNum => $line) {
	echo "Line $lineNum: $line\n";
}
```


rename(string $origin, string $target, bool $overwrite=true): void .[method]
----------------------------------------------------------------------------

Renames or moves a file or a directory specified by `$origin` to `$target`. Overwrites existing files and directories by default. If `$overwrite` is set to `false` and `$target` already exists, throws an exception `Nette\InvalidStateException`. Throws an exception `Nette\IOException` on error occurred.

```php
FileSystem::rename('/path/to/source', '/path/to/dest', overwrite: true);
```


write(string $file, string $content, int $mode=0666): void .[method]
--------------------------------------------------------------------

Writes the `$content` to a `$file`. Throws an exception `Nette\IOException` on error occurred.

```php
FileSystem::write('/path/to/file', $content);
```


Paths
=====


isAbsolute(string $path): bool .[method]
----------------------------------------

Determines if the `$path` is absolute.

```php
FileSystem::isAbsolute('../backup'); // false
FileSystem::isAbsolute('/backup');   // true
FileSystem::isAbsolute('C:/backup'); // true
```


joinPaths(string ...$segments): string .[method]
------------------------------------------------
Joins all segments of the path and normalizes the result.

```php
FileSystem::joinPaths('a', 'b', 'file.txt'); // 'a/b/file.txt'
FileSystem::joinPaths('/a/', '/b/');         // '/a/b/'
FileSystem::joinPaths('/a/', '/../b');       // '/b'
```


normalizePath(string $path): string .[method]
---------------------------------------------
Normalizes `..` and `.` and directory separators in path.

```php
FileSystem::normalizePath('/file/.');        // '/file/'
FileSystem::normalizePath('\file\..');       // '/file'
FileSystem::normalizePath('/file/../..');    // '/..'
FileSystem::normalizePath('file/../../bar'); // '/../bar'
```


unixSlashes(string $path): string .[method]
-------------------------------------------

Converts slashes to `/` used on Unix systems.

```php
$path = FileSystem::unixSlashes($path);
```


platformSlashes(string $path): string .[method]
-----------------------------------------------

Converts slashes to characters specific to the current platform, i.e. `\` on Windows and `/` elsewhere.

```php
$path = FileSystem::platformSlashes($path);
```


Static vs Non-static Approach
=============================

To easily replace the `FileSystem` class with another class for example for testing purposes, use it non-statically:

```php
class AnyClassUsingFileSystem
{
	public function __construct(
		private FileSystem $fileSystem,
	) {
	}


	public function readConfig(): string
	{
		return $this->fileSystem->read(/* ... */);
	}

	...
}
```