shell bypass 403
# A better PHP backtrace
[](https://packagist.org/packages/spatie/backtrace)
[](https://packagist.org/packages/spatie/backtrace)
To get the backtrace in PHP you can use the `debug_backtrace` function. By default, it can be hard to work with. The
reported function name for a frame is skewed: it belongs to the previous frame. Also, options need to be passed using a bitmask.
This package provides a better way than `debug_backtrace` to work with a back trace. Here's an example:
```php
// returns an array with `Spatie\Backtrace\Frame` instances
$frames = Spatie\Backtrace\Backtrace::create()->frames();
$firstFrame = $frames[0];
$firstFrame->file; // returns the file name
$firstFrame->lineNumber; // returns the line number
$firstFrame->class; // returns the class name
```
## Support us
[<img src="https://github-ads.s3.eu-central-1.amazonaws.com/backtrace.jpg?t=1" width="419px" />](https://spatie.be/github-ad-click/backtrace)
We invest a lot of resources into creating [best in class open source packages](https://spatie.be/open-source). You can
support us by [buying one of our paid products](https://spatie.be/open-source/support-us).
We highly appreciate you sending us a postcard from your hometown, mentioning which of our package(s) you are using.
You'll find our address on [our contact page](https://spatie.be/about-us). We publish all received postcards
on [our virtual postcard wall](https://spatie.be/open-source/postcards).
## Installation
You can install the package via composer:
```bash
composer require spatie/backtrace
```
## Usage
This is how you can create a backtrace instance:
```php
$backtrace = Spatie\Backtrace\Backtrace::create();
```
### Getting the frames
To get all the frames you can call `frames`.
```php
$frames = $backtrace->frames(); // contains an array with `Spatie\Backtrace\Frame` instances
```
A `Spatie\Backtrace\Frame` has these properties:
- `file`: the name of the file
- `lineNumber`: the line number
- `arguments`: the arguments used for this frame. Will be `null` if `withArguments` was not used.
- `class`: the class name for this frame. Will be `null` if the frame concerns a function.
- `method`: the method used in this frame
- `applicationFrame`: contains `true` is this frame belongs to your application, and `false` if it belongs to a file in
the vendor directory
### Collecting arguments
For performance reasons, the frames of the back trace will not contain the arguments of the called functions. If you
want to add those use the `withArguments` method.
```php
$backtrace = Spatie\Backtrace\Backtrace::create()->withArguments();
```
#### Reducing arguments
For viewing purposes, arguments can be reduced to a string:
```php
$backtrace = Spatie\Backtrace\Backtrace::create()->withArguments()->reduceArguments();
```
By default, some typical types will be reduced to a string. You can define your own reduction algorithm per type by implementing an `ArgumentReducer`:
```php
class DateTimeWithOtherFormatArgumentReducer implements ArgumentReducer
{
public function execute($argument): ReducedArgumentContract
{
if (! $argument instanceof DateTimeInterface) {
return UnReducedArgument::create();
}
return new ReducedArgument(
$argument->format('d/m/y H:i'),
get_class($argument),
);
}
}
```
This is a copy of the built-in argument reducer for `DateTimeInterface` where we've updated the format. An `UnReducedArgument` object is returned when the argument is not of the expected type. A `ReducedArgument` object is returned with the reduced value of the argument and the original type of the argument.
The reducer can be used as such:
```php
$backtrace = Spatie\Backtrace\Backtrace::create()->withArguments()->reduceArguments(
Spatie\Backtrace\Arguments\ArgumentReducers::default([
new DateTimeWithOtherFormatArgumentReducer()
])
);
```
Which will first execute the new reducer and then the default ones.
### Setting the application path
You can use the `applicationPath` to pass the base path of your app. This value will be used to determine whether a
frame is an application frame, or a vendor frame. Here's an example using a Laravel specific function.
```php
$backtrace = Spatie\Backtrace\Backtrace::create()->applicationPath(base_path());
```
### Getting a certain part of a trace
If you only want to have the frames starting from a particular frame in the backtrace you can use
the `startingFromFrame` method:
```php
use Spatie\Backtrace\Backtrace;
use Spatie\Backtrace\Frame;
$frames = Backtrace::create()
->startingFromFrame(function (Frame $frame) {
return $frame->class === MyClass::class;
})
->frames();
```
With this code, all frames before the frame that concerns `MyClass` will have been filtered out.
Alternatively, you can use the `offset` method, which will skip the given number of frames. In this example the first 2 frames will not end up in `$frames`.
```php
$frames = Spatie\Backtrace\Backtrace::create()
->offset(2)
->frames();
```
### Limiting the number of frames
To only get a specific number of frames use the `limit` function. In this example, we'll only get the first two frames.
```php
$frames = Spatie\Backtrace\Backtrace::create()
->limit(2)
->frames();
```
### Getting a backtrace for a throwable
Here's how you can get a backtrace for a throwable.
```php
$frames = Spatie\Backtrace\Backtrace::createForThrowable($throwable)
```
Because we will use the backtrace that is already available the throwable, the frames will always contain the arguments used.
## Testing
``` bash
composer test
```
## Changelog
Please see [CHANGELOG](CHANGELOG.md) for more information on what has changed recently.
## Contributing
Please see [CONTRIBUTING](https://github.com/spatie/.github/blob/main/CONTRIBUTING.md) for details.
## Security Vulnerabilities
Please review [our security policy](../../security/policy) on how to report security vulnerabilities.
## Credits
- [Freek Van de Herten](https://github.com/freekmurze)
- [All Contributors](../../contributors)
## License
The MIT License (MIT). Please see [License File](LICENSE.md) for more information.