README

Ulrack Fallback

This package contains an implementation for implementing a fallback system within a PHP application.

Installation

To install the package run the following command:

composer require ulrack/fallback

Usage

A single fallback consists of one FallbackStack with multiple Fallbacks.

Creating a Fallback

A fallback can be created by providing it with a callable, a (optional) validator and a (optional) set of parameters. The callable will be executed when it is reached inside the stack. The validator (see package: ulrack/validator) will be used to verify the output of the callable. The parameters are variadic and will override the parameters send by the stack.

An implementation would look like:

<?php

use Ulrack\Fallback\Component\Fallback;
use Ulrack\Validator\Component\Logical\ConstValidator;

$class = new class {
    /**
     * Returns the input.
     *
     * @param string $input
     *
     * @return string
     */
    public function foo(string $input): string
    {
        return $input;
    }
};

$validator = new ConstValidator('bar');

$fallback = new Fallback([$class, 'foo'], $validator);

The fallback stack can be created after this. The fallback stack takes a validator as an argument. The function addFallback is used to add the fallback to the stack. This function takes the Fallback and a position as its arguments. The stack can then be invoked with a set of parameters.

<?php

use Ulrack\Fallback\Component\FallbackStack;
use Ulrack\Validator\Component\Type\StringValidator;

$validator = new StringValidator();

$fallbackStack = new FallbackStack($validator);

$fallbackStack->addFallback($fallback, 0);

$fallbackStack('bar');

Change log

Please see CHANGELOG for more information on what has changed recently.

Contributing

Please see CONTRIBUTING and CODE_OF_CONDUCT for details.

MIT License

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

ulrack / fallback

Maintainers

Details