Laravel 5.1 defines events, event listeners, and triggering event examples

Here we are based on the Model + cache based on the article to check the deletion of the article after the preservation of the text of the cache to further optimize the processing. We treat the article save (new/modified) as an event that saves the content of the article to the cache and puts it in the listener:

1, registration Events-Listeners

First we need to register the mapping between the event and the Listener in Eventserviceprovider:

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protected $listen = [ ' App\events\postsaved ' =>[ ' App\listeners\savedatatocache ' ] ];

Then we run the following artisan command in the project root directory:

PHP Artisan Event:generate

This command generates postsaved.php in the App/events directory and generates savedatatocache.php in the App/listeners directory.

2. Defining event Classes

Next we edit the event class postsaved as follows:

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<?php namespace App\events; Use app\events\event; Use App\models\post; Use Illuminate\queue\serializesmodels; Use Illuminate\contracts\broadcasting\shouldbroadcast; Class Postsaved extends Event { Use Serializesmodels; /** * Create a new event instance. * * @return void */ Public function __construct (Post $post) { $this->post = $post; } /** * Get the channels the event should is broadcast on. * * @return Array */ Public Function Broadcaston () { return []; } }

We inject a post instance into the constructor to pass to Postsaved.

3. Define Listener Class

We then define the Listener class Savedatatocache, where the listener class uses the handle method to receive the event instance and execute the business logic that responds to the event, where the post instance received is saved to the cache:

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<?php namespace App\listeners; Use app\events\postsaved; Use Cache; Use Log; Use Illuminate\queue\interactswithqueue; Use Illuminate\contracts\queue\shouldqueue; Class Savedatatocache { /** * Create the event listener. * * @return void */ Public Function __construct () { // } /** * Handle the event. * * @param postsaved $event * @return void */ Public function handle (postsaved $event) { $post = $event->post; $key = ' post_ '. $post->id; Cache::p ut ($key, $post, 60*24*7); Log::info (' Save article to cache success! ', [' id ' => $post->id, ' title ' => $post->title]); } }

The business logic is simple: Get the story instance from the injected postsaved and save it to the cache, and log the action to the journal.

4. Triggering event

Finally, we'll test the article save events and their listeners.

To trigger the article save event, you can use the fire method provided by the event façade to modify the store method in Postcontroller as follows:

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Public function Store (Request $request) { $title = $request->input (' title '); $content = $request->input (' content '); $post = new Post; $post->title = $title; $post->content = $content; $post->save (); Event::fire (New postsaved ($post)); Return Redirect ()->route (' Post.show ', [' Post ' => $post]); }

Then modify the Update method as follows:

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Public Function update (Request $request, $id) {     $ Post = Post::find ($id);     if (! $post)         exit (' Specifies that the article does not exist! ');     $title = $request->input (' title ');     $content = $request->input (' content ');     $post->title = $title;     $post->content = $content;     $post->save ();     Event::fire (New postsaved ($post));     return Redirect ()->route (' Post.show ', [' Post ' => $post]); }

Access Http://laravel.app:8000/post/create in the browser, fill in the title and article content:

Click on the submit page to jump to the article details page, at this point to view the log storage/logs/laravel.log, you can see the corresponding log records:

[2015-11-10 23:14:12] Local.info: Save article to cache success! {"id": "title": "Test Event Add"}
Indicates that the article save event has been triggered and the listener monitors the event and then saves it to the cache and logs the log.