doc
7 years ago
src
7 years ago
CONTRIBUTING.md
7 years ago
LICENSE
7 years ago
README.md
7 years ago
composer.json
7 years ago
README.md
235 lines
| 1 | # Invoker |
| 2 | |
| 3 | Generic and extensible callable invoker. |
| 4 | |
| 5 | [](https://travis-ci.org/PHP-DI/Invoker](https://travis-ci.org/PHP-DI/Invoker](https://travis-ci.org/PHP-DI/Invoker) |
| 6 | [](https://coveralls.io/r/PHP-DI/Invoker?branch=master](https://coveralls.io/r/PHP-DI/Invoker?branch=master](https://coveralls.io/r/PHP-DI/Invoker?branch=master) |
| 7 | [](https://scrutinizer-ci.com/g/PHP-DI/Invoker/?branch=master](https://scrutinizer-ci.com/g/PHP-DI/Invoker/?branch=master](https://scrutinizer-ci.com/g/PHP-DI/Invoker/?branch=master) |
| 8 | [](https://packagist.org/packages/PHP-DI/invoker](https://packagist.org/packages/PHP-DI/invoker](https://packagist.org/packages/PHP-DI/invoker) |
| 9 | |
| 10 | ## Why? |
| 11 | |
| 12 | Who doesn't need an over-engineered `call_user_func()`? |
| 13 | |
| 14 | ### Named parameters |
| 15 | |
| 16 | Does this [](http://silex.sensiolabs.orgSilex](http://silex.sensiolabs.org](http://silex.sensiolabs.org) example look familiar: |
| 17 | |
| 18 | ```php |
| 19 | $app->get('/project/{project}/issue/{issue}', function ($project, $issue) { |
| 20 | // ... |
| 21 | }); |
| 22 | ``` |
| 23 | |
| 24 | Or this command defined with [](https://github.com/mnapoli/silly#usageSilly](https://github.com/mnapoli/silly#usage](https://github.com/mnapoli/silly#usage): |
| 25 | |
| 26 | ```php |
| 27 | $app->command('greet [name] [--yell]', function ($name, $yell) { |
| 28 | // ... |
| 29 | }); |
| 30 | ``` |
| 31 | |
| 32 | Same pattern in [](http://www.slimframework.comSlim](http://www.slimframework.com](http://www.slimframework.com): |
| 33 | |
| 34 | ```php |
| 35 | $app->get('/hello/:name', function ($name) { |
| 36 | // ... |
| 37 | }); |
| 38 | ``` |
| 39 | |
| 40 | You get the point. These frameworks invoke the controller/command/handler using something akin to named parameters: whatever the order of the parameters, they are matched by their name. |
| 41 | |
| 42 | **This library allows to invoke callables with named parameters in a generic and extensible way.** |
| 43 | |
| 44 | ### Dependency injection |
| 45 | |
| 46 | Anyone familiar with AngularJS is familiar with how dependency injection is performed: |
| 47 | |
| 48 | ```js |
| 49 | angular.controller('MyController', ['dep1', 'dep2', function(dep1, dep2) { |
| 50 | // ... |
| 51 | }]); |
| 52 | ``` |
| 53 | |
| 54 | In PHP we find this pattern again in some frameworks and DI containers with partial to full support. For example in Silex you can type-hint the application to get it injected, but it only works with `Silex\Application`: |
| 55 | |
| 56 | ```php |
| 57 | $app->get('/hello/{name}', function (Silex\Application $app, $name) { |
| 58 | // ... |
| 59 | }); |
| 60 | ``` |
| 61 | |
| 62 | In Silly, it only works with `OutputInterface` to inject the application output: |
| 63 | |
| 64 | ```php |
| 65 | $app->command('greet [name]', function ($name, OutputInterface $output) { |
| 66 | // ... |
| 67 | }); |
| 68 | ``` |
| 69 | |
| 70 | [](http://php-di.org/doc/container.htmlPHP-DI](http://php-di.org/doc/container.html](http://php-di.org/doc/container.html) provides a way to invoke a callable and resolve all dependencies from the container using type-hints: |
| 71 | |
| 72 | ```php |
| 73 | $container->call(function (Logger $logger, EntityManager $em) { |
| 74 | // ... |
| 75 | }); |
| 76 | ``` |
| 77 | |
| 78 | **This library provides clear extension points to let frameworks implement any kind of dependency injection support they want.** |
| 79 | |
| 80 | ### TL/DR |
| 81 | |
| 82 | In short, this library is meant to be a base building block for calling a function with named parameters and/or dependency injection. |
| 83 | |
| 84 | ## Installation |
| 85 | |
| 86 | ```sh |
| 87 | $ composer require PHP-DI/invoker |
| 88 | ``` |
| 89 | |
| 90 | ## Usage |
| 91 | |
| 92 | ### Default behavior |
| 93 | |
| 94 | By default the `Invoker` can call using named parameters: |
| 95 | |
| 96 | ```php |
| 97 | $invoker = new Invoker\Invoker; |
| 98 | |
| 99 | $invoker->call(function () { |
| 100 | echo 'Hello world!'; |
| 101 | }); |
| 102 | |
| 103 | // Simple parameter array |
| 104 | $invoker->call(function ($name) { |
| 105 | echo 'Hello ' . $name; |
| 106 | }, ['John']); |
| 107 | |
| 108 | // Named parameters |
| 109 | $invoker->call(function ($name) { |
| 110 | echo 'Hello ' . $name; |
| 111 | }, [ |
| 112 | 'name' => 'John' |
| 113 | ]); |
| 114 | |
| 115 | // Use the default value |
| 116 | $invoker->call(function ($name = 'world') { |
| 117 | echo 'Hello ' . $name; |
| 118 | }); |
| 119 | |
| 120 | // Invoke any PHP callable |
| 121 | $invoker->call(['MyClass', 'myStaticMethod']); |
| 122 | |
| 123 | // Using Class::method syntax |
| 124 | $invoker->call('MyClass::myStaticMethod'); |
| 125 | ``` |
| 126 | |
| 127 | Dependency injection in parameters is supported but needs to be configured with your container. Read on or jump to [](#built-in-support-for-dependency-injection*Built-in support for dependency injection*](#built-in-support-for-dependency-injection](#built-in-support-for-dependency-injection) if you are impatient. |
| 128 | |
| 129 | Additionally, callables can also be resolved from your container. Read on or jump to [](#resolving-callables-from-a-container*Resolving callables from a container*](#resolving-callables-from-a-container](#resolving-callables-from-a-container) if you are impatient. |
| 130 | |
| 131 | ### Parameter resolvers |
| 132 | |
| 133 | Extending the behavior of the `Invoker` is easy and is done by implementing a [](https://github.com/PHP-DI/Invoker/blob/master/src/ParameterResolver/ParameterResolver.php`ParameterResolver`](https://github.com/PHP-DI/Invoker/blob/master/src/ParameterResolver/ParameterResolver.php](https://github.com/PHP-DI/Invoker/blob/master/src/ParameterResolver/ParameterResolver.php). |
| 134 | |
| 135 | This is explained in details the [](doc/parameter-resolvers.mdParameter resolvers documentation](doc/parameter-resolvers.md](doc/parameter-resolvers.md). |
| 136 | |
| 137 | #### Built-in support for dependency injection |
| 138 | |
| 139 | Rather than have you re-implement support for dependency injection with different containers every time, this package ships with 2 optional resolvers: |
| 140 | |
| 141 | - [](https://github.com/PHP-DI/Invoker/blob/master/src/ParameterResolver/Container/TypeHintContainerResolver.php`TypeHintContainerResolver`](https://github.com/PHP-DI/Invoker/blob/master/src/ParameterResolver/Container/TypeHintContainerResolver.php](https://github.com/PHP-DI/Invoker/blob/master/src/ParameterResolver/Container/TypeHintContainerResolver.php) |
| 142 | |
| 143 | This resolver will inject container entries by searching for the class name using the type-hint: |
| 144 | |
| 145 | ```php |
| 146 | $invoker->call(function (Psr\Logger\LoggerInterface $logger) { |
| 147 | // ... |
| 148 | }); |
| 149 | ``` |
| 150 | |
| 151 | In this example it will `->get('Psr\Logger\LoggerInterface')` from the container and inject it. |
| 152 | |
| 153 | This resolver is only useful if you store objects in your container using the class (or interface) name. Silex or Symfony for example store services under a custom name (e.g. `twig`, `db`, etc.) instead of the class name: in that case use the resolver shown below. |
| 154 | |
| 155 | - [`ParameterNameContainerResolver`](https://github.com/PHP-DI/Invoker/blob/master/src/ParameterResolver/Container/ParameterNameContainerResolver.php) |
| 156 | |
| 157 | This resolver will inject container entries by searching for the name of the parameter: |
| 158 | |
| 159 | ```php |
| 160 | $invoker->call(function ($twig) { |
| 161 | // ... |
| 162 | }); |
| 163 | ``` |
| 164 | |
| 165 | In this example it will `->get('twig')` from the container and inject it. |
| 166 | |
| 167 | These resolvers can work with any dependency injection container compliant with [container-interop](https://github.com/container-interop/container-interop). If you container is not compliant you can use the [Acclimate](https://github.com/jeremeamia/acclimate-container) package. |
| 168 | |
| 169 | Setting up those resolvers is simple: |
| 170 | |
| 171 | ```php |
| 172 | // $container must be an instance of Interop\Container\ContainerInterface |
| 173 | $container = ... |
| 174 | |
| 175 | $containerResolver = new TypeHintContainerResolver($container); |
| 176 | // or |
| 177 | $containerResolver = new ParameterNameContainerResolver($container); |
| 178 | |
| 179 | $invoker = new Invoker\Invoker; |
| 180 | // Register it before all the other parameter resolvers |
| 181 | $invoker->getParameterResolver()->prependResolver($containerResolver); |
| 182 | ``` |
| 183 | |
| 184 | You can also register both resolvers at the same time if you wish by prepending both. Implementing support for more tricky things is easy and up to you! |
| 185 | |
| 186 | ### Resolving callables from a container |
| 187 | |
| 188 | The `Invoker` can be wired to your DI container to resolve the callables. |
| 189 | |
| 190 | For example with an invokable class: |
| 191 | |
| 192 | ```php |
| 193 | class MyHandler |
| 194 | { |
| 195 | public function __invoke() |
| 196 | { |
| 197 | // ... |
| 198 | } |
| 199 | } |
| 200 | |
| 201 | // By default this doesn't work: an instance of the class should be provided |
| 202 | $invoker->call('MyHandler'); |
| 203 | |
| 204 | // If we set up the container to use |
| 205 | $invoker = new Invoker\Invoker(null, $container); |
| 206 | // Now 'MyHandler' is resolved using the container! |
| 207 | $invoker->call('MyHandler'); |
| 208 | ``` |
| 209 | |
| 210 | The same works for a class method: |
| 211 | |
| 212 | ```php |
| 213 | class WelcomeController |
| 214 | { |
| 215 | public function home() |
| 216 | { |
| 217 | // ... |
| 218 | } |
| 219 | } |
| 220 | |
| 221 | // By default this doesn't work: home() is not a static method |
| 222 | $invoker->call(['WelcomeController', 'home']); |
| 223 | |
| 224 | // If we set up the container to use |
| 225 | $invoker = new Invoker\Invoker(null, $container); |
| 226 | // Now 'WelcomeController' is resolved using the container! |
| 227 | $invoker->call(['WelcomeController', 'home']); |
| 228 | // Alternatively we can use the Class::method syntax |
| 229 | $invoker->call('WelcomeController::home'); |
| 230 | ``` |
| 231 | |
| 232 | That feature can be used as the base building block for a framework's dispatcher. |
| 233 | |
| 234 | Again, any [container-interop](https://github.com/container-interop/container-interop) compliant container can be provided, and [Acclimate](https://github.com/jeremeamia/acclimate-container) can be used for incompatible containers. |
| 235 |