https://github.com/bcremer/LineReader
Read large files line by line in a memory efficient (constant) way.
https://github.com/bcremer/LineReader
large-files linereader php
Last synced: 11 months ago
JSON representation
Read large files line by line in a memory efficient (constant) way.
- Host: GitHub
- URL: https://github.com/bcremer/LineReader
- Owner: bcremer
- License: mit
- Created: 2016-08-03T20:11:22.000Z (almost 10 years ago)
- Default Branch: main
- Last Pushed: 2023-01-27T12:18:16.000Z (over 3 years ago)
- Last Synced: 2024-11-09T03:46:59.534Z (over 1 year ago)
- Topics: large-files, linereader, php
- Language: PHP
- Homepage:
- Size: 36.1 KB
- Stars: 30
- Watchers: 4
- Forks: 6
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
- Changelog: CHANGELOG.md
- License: LICENSE
Awesome Lists containing this project
README
# LineReader
[![Latest Version on Packagist][ico-version]][link-packagist]
[![Software License][ico-license]](LICENSE.md)
[![Build Status][ico-ghactions]][link-ghactions]
LineReader is a library to read large files line by line in a memory efficient (constant) way.
## Install
Via Composer
```bash
$ composer require bcremer/line-reader
```
## Usage
Given we have a textfile (`some/file.txt`) with lines like:
```
Line 1
Line 2
Line 3
Line 4
Line 5
Line 6
Line 7
Line 8
Line 9
Line 10
```
Also let's assume the namespace is imported to keep the examples dense:
```
use Bcremer\LineReader\LineReader;
```
### Read forwards
```php
foreach (LineReader::readLines('some/file.txt') as $line) {
echo $line . "\n"
}
```
The output will be:
```
Line 1
Line 2
Line 3
Line 4
Line 5
...
```
To set an offset or a limit use the `\LimitIterator`:
```php
$lineGenerator = LineReader::readLines('some/file.txt');
$lineGenerator = new \LimitIterator($lineGenerator, 2, 5);
foreach ($lineGenerator as $line) {
echo $line . "\n"
}
```
Will output line 3 to 7
```
Line 3
Line 4
Line 5
Line 6
Line 7
```
### Read backwards
```php
foreach (LineReader::readLinesBackwards('some/file.txt') as $line) {
echo $line;
}
```
```
Line 10
Line 9
Line 8
Line 7
Line 6
...
```
Example: Read the last 5 lines in forward order:
```php
$lineGenerator = LineReader::readLinesBackwards('some/file.txt');
$lineGenerator = new \LimitIterator($lineGenerator, 0, 5);
$lines = array_reverse(iterator_to_array($lineGenerator));
foreach ($line as $line) {
echo $line;
}
```
```
Line 6
Line 7
Line 8
Line 9
Line 10
```
## Testing
```bash
$ composer test
```
```bash
$ TEST_MAX_LINES=200000 composer test
```
## License
The MIT License (MIT). Please see [License File](LICENSE) for more information.
[ico-version]: https://img.shields.io/packagist/v/bcremer/line-reader.svg?style=flat-square
[ico-license]: https://img.shields.io/badge/license-MIT-brightgreen.svg?style=flat-square
[link-packagist]: https://packagist.org/packages/bcremer/line-reader
[ico-ghactions]: https://github.com/bcremer/LineReader/workflows/Build/badge.svg
[link-ghactions]: https://github.com/bcremer/LineReader/actions?query=workflow%3ABuild