Robert Basic's blog

Configure Fedora's firewall for Vagrant

by Robert Basic on December 09, 2016.

This one’s been in my drafts for a long time, might as well publish it.

FirewallD, Fedora’s firewall, has a set of zones, which basically enables to configure trusted network connections inside these zones. You can read more about FirewallD on it’s wiki page.

Whenever I bring up a Vagrant box for the first time, Fedora’s firewall blocks the NFS shares, because the new Vagrant network interface does not belong to any zone. The usual symptom of this is that Vagrant gets stuck on the mounting NFS shares step.

I have a zone called FedoraWorkstation that I use for all the Vagrant boxes I have on my laptop. This zone has a list of services that are allowed:

robert@odin ~$ sudo firewall-cmd --zone FedoraWorkstation --list-services
dhcpv6-client rpc-bind nfs mountd ssh samba-client

You can use any other zone you like, but you need to have the rpc-bind, nfs and mountd services allowed for that zone.

After bringing up the Vagrant box, we need to figure out what’s the name of the new Vagrant interface and add it to the firewall zone. Vagrant interfaces follow the naming schema of vboxnetX where X is a number:

robert@odin ~$ ip link show | grep "state UP" | grep "vbox"
7: vboxnet3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP mode DEFAULT group default qlen 1000

From this we can see that the name of the interface is vboxnet3.

Let’s add it to the FedoraWorkstation zone and reload:

robert@odin ~$ sudo firewall-cmd --zone FedoraWorkstation --add-interface vboxnet3 --permanent
success
robert@odin ~$ sudo firewall-cmd --reload
success

Finally let’s make sure that the interface was indeed added:

robert@odin ~$ sudo firewall-cmd --zone FedoraWorkstation --list-interfaces
vboxnet3 vboxnet2 vboxnet0

And that’s it. Happy hackin’!

Tags: configuration, fedora, firewall, vagrant.
Categories: Development, Software.

Events in a Zend Expressive application

by Robert Basic on August 04, 2016.

Three weeks ago I wrote a post on how to utilize Tactician in a Zend Expressive application. Today I want to expand on that post a little by adding the possibility to trigger and listen to events using the Zend EventManager component.

Using events allows our application to respond to different events that occur during a request. For example, when a user registers a new account, our application can trigger an event, UserRegistered, that can let the rest of our application know when a new registration happens. With the help of the EventManager we attach listeners to that event. When the UserRegistered event is triggered, the event manager will invoke all the listeners that are listening to that particular event.

This allows for a better separation of concerns in some cases, because if we take this approach, our code that deals with registering new users doesn’t care any more what happens after that — do we send out a welcoming email to the user, a notification to the site admins, create a log entry somewhere… It just registers a new account, triggers the event and that’s it.

Let’s see some code

As I mentioned earlier, this post expands on my previous post, so all we are going to add is an event that gets triggered when the Ping command is handled, an event listener that listens to that event and wire it all together with the event manager.

Let’s include the Zend EventManager in our project with composer:

$ composer require zendframework/zend-eventmanager

Next we expand the factory for the Ping command handler. We create an EventManager object that we will pass to the Ping command handler, so that we can trigger events:

src/App/CommandHandler/PingFactory.php

diff --git a/src/App/CommandHandler/PingFactory.php b/src/App/CommandHandler/PingFactory.php
index e995d1a..0737631 100644
--- a/src/App/CommandHandler/PingFactory.php
+++ b/src/App/CommandHandler/PingFactory.php
@@ -3,6 +3,7 @@
 namespace App\CommandHandler;
 
 use Interop\Container\ContainerInterface;
+use Zend\EventManager\EventManager;
 
 class PingFactory
 {
@@ -10,6 +11,11 @@ class PingFactory
     {
         $logPath = '/tmp/ping-command.log';
 
-        return new Ping($logPath);
+        $events = new EventManager();
+        $events->setIdentifiers([
+            Ping::class
+        ]);
+
+        return new Ping($logPath, $events);
     }
}

Later on we will use the same event manager to attach event listeners to our events.

In the Ping command handler we use the event manager, that we pass in as a constructor argument from the ping command handler factory, to trigger events:

src/App/CommandHandler/Ping.php

diff --git a/src/App/CommandHandler/Ping.php b/src/App/CommandHandler/Ping.php
index 538e3af..9768738 100644
--- a/src/App/CommandHandler/Ping.php
+++ b/src/App/CommandHandler/Ping.php
@@ -2,15 +2,19 @@
 
 namespace App\CommandHandler;
 
+use Zend\EventManager\EventManagerInterface;
 use App\Command\Ping as PingCommand;
 
 class Ping
 {
     private $logPath;
 
-    public function __construct($logPath)
+    private $events;
+
+    public function __construct($logPath, EventManagerInterface $events)
     {
         $this->logPath = $logPath;
+        $this->events = $events;
     }
 
     public function __invoke(PingCommand $pingCommand)
@@ -18,5 +22,12 @@ class Ping
         $commandTime = $pingCommand->getCommandTime();
 
         file_put_contents($this->logPath, $commandTime . PHP_EOL, FILE_APPEND);
+
+        $params = [
+            'command_time' => $commandTime,
+            'event_time' => time(),
+        ];
+
+        $this->events->trigger('ping_command_handled', $this, $params);
     }
}

The main part is the call to the trigger method on the event manager. The first argument, ping_command_handled, is the event’s name. We will use that event name to attach to it later. The second argument is the target of the event and usually it’s the object instance that triggers the event. Finally with the third argument we can send out optional parameters with the event which we can access in our event listeners.

Even though we have no listeners attached to the event, our application will continue to work perfectly fine, because an event is not required to have any listeners. It doesn’t make much sense to have events without listeners, but it wouldn’t break our application.

Shhh… Listen!

The simplest way to attach a listener to the event would be to tell the event manager to call a callable every time the event is triggered. This would also mean we need to set up any and all dependencies our event listeners have, at the moment of attaching the listener to the event, even though the event can end up not being triggered at all. All that dependency set up can be costly and wasteful.

Zend EventManager comes with lazy listeners that allows to fetch event listeners from a container-interop compatible container. This lets us to set up the dependency graph for an event listener in a factory, which will be invoked by the lazy listener only when the event we are listening to is triggered. If the event is triggered, the lazy listener will fetch the event listener from the container along with it’s dependencies, but if the event is not triggered, nothing will happen. Super useful!

Let’s attach our event listener to the event using the lazy listener:

src/App/CommandHandler/PingFactory.php

diff --git a/src/App/CommandHandler/PingFactory.php b/src/App/CommandHandler/PingFactory.php
index 0737631..5ce9c7e 100644
--- a/src/App/CommandHandler/PingFactory.php
+++ b/src/App/CommandHandler/PingFactory.php
@@ -4,6 +4,7 @@ namespace App\CommandHandler;
 
 use Interop\Container\ContainerInterface;
 use Zend\EventManager\EventManager;
+use Zend\EventManager\LazyListener;
+use App\EventListener\Ping as PingEventListener;
 
 class PingFactory
 {
@@ -16,6 +17,13 @@ class PingFactory
             Ping::class
         ]);
 
+        $lazyListener = new LazyListener([
+            'listener' => PingEventListener::class,
+            'method' => 'onPingCommandHandled',
+        ], $container);
+
+        $events->attach('ping_command_handled', $lazyListener);
+
         return new Ping($logPath, $events);
     }
}

We create a new LazyListener object and as the first argument to it we pass an array with the actual event listener and method that will be called when the event is triggered. The second argument is the container-interop compatible container, which knows how to build our event listener.

After that we attach the lazy listener to the events we are interested in, in this case the event called ping_command_handled. Once that event gets triggered, the lazy listener will get our PingEventListener from the container and call the onPingCommandHandled method on it.

Let’s quickly tell the container how to create our event listener:

config/autoload/dependencies.global.php

diff --git a/config/autoload/dependencies.global.php b/config/autoload/dependencies.global.php
index 794304e..cf47c99 100644
--- a/config/autoload/dependencies.global.php
+++ b/config/autoload/dependencies.global.php
@@ -21,6 +21,7 @@ return [
             Helper\UrlHelper::class => Helper\UrlHelperFactory::class,
             'CommandBus' => App\CommandBusFactory::class,
             App\CommandHandler\Ping::class => App\CommandHandler\PingFactory::class,
+            App\EventListener\Ping::class => App\EventListener\Ping::class,
         ],
     ],
];

And finally our event listener looks something like this:

src/App/EventListener/Ping.php

<?php
namespace App\EventListener;
use Interop\Container\ContainerInterface;
use Zend\EventManager\Event;
class Ping
{
    public function __invoke(ContainerInterface $container)
    {
        // Grab some dependencies from the $container
        // And return self
        return new self();
    }

    public function onPingCommandHandled(Event $event)
    {
        // Do something with the $event here
        $name = $event->getName();
        $target = $event->getTarget();
        $params = $event->getParams();
    }
}

When the container grabs our event listener the __invoke method will be invoked at which point we can grab the event listener’s dependencies from the container. Once the event listener object is created, the onPingCommandHandled method will be called by the event manager when the event is triggered.

Happy hackin’!

Tags: container, event listener, event manager, events, php, zend expressive.
Categories: Development, Programming.

Hiking the Uvac special nature reserve

by Robert Basic on July 27, 2016.

In 2014 my wife Senka and I went on a camping vacation in Greece, on the Lefkas island. It was the first time camping for her, while I did some camping the year before. We quickly realised that we both enjoy camping very much and agreed to go on as many camping trips as possible.

The following year we went on a 12 day long camping and hiking vacation in Italy. The weather had different plans for us, so we only managed to do two hikes there — one in Seiser Alm and one in Cinque Terre.

This year for our honeymoon we went to Norway where we managed to do an amazing 4 hikes for the 8 days we were there. The view from Preikestolen is mind-boggling.

This past weekend the two of us went on a camping and hiking weekend getaway at the Uvac special nature reserve. Apparently this was our 10th hike so I thought it would only be fitting to remember it with a blog post. I might write about our other experiences in the future.

We chose Uvac as we agreed to see more of our country, the entire region is just gorgeous, the nature is barely touched by humans and the reserve is the home to the endangered Griffon Vulture.

Choosing the trail

There are only a handful of resources online about the camping and hiking possibilities around here (this is mostly true for all of Serbia, not just the Uvac region). We found a couple of hiking trails that we liked and a detailed inspection of one of the trails on Open Street Map and Google Maps revealed there’s a camping site by the trail, on the banks of the Sjenica lake. I got in contact with the reserve’s custodians who got me in touch with the ranger who is responsible for that area. They were all very helpful over the phone and answered all my questions in a couple of minutes.

The trail is the Uvac meanders and Molitva (Prayer) peak trail.

Driving from Novi Sad

The drive from Novi Sad to the camp took us some 7 hours, with one stop. The route was Novi Sad — Šabac — Valjevo — Kosjerić — Požega — Užice — Zlatibor — Nova Varoš — Sjenica — camp. We left the city in the rush hour and the traffic was pretty heavy until Šabac which is some 70kms away. The road from there was surprisingly good, with only maybe two patches of the asphalt being really bad for a total of cca. 30km. A slow, but not a tiring drive all things considered. The nature along the way makes up for it.

Arriving at the camp

The path to the camp is not clearly marked on the road. There is a junction at which we had to go off of the main road and there’s maybe a kilometer or so of gravel road to get to the camp. I was hoping to arrive there while there was still some daylight left, but we ended up arriving just as the Sun set. We were welcomed by the campers and I’m not even sure there was an “official” person from the camp or from the reserve there. They helped us pick a spot for our tent and invited us for a barbecue dinner after we were all set up. A bottle of rakija was also going around.

The camp is not like the camps we stayed at before. It has no showers or toilette facilities. There’s one fountain with spring water and one of those wooden field toilets. There are no visible tent spots, it’s more of a who settles where kind of a camp. A bit chaotic, but it does have it’s charm. In the mornings the camp site and the surounding area was covered in a mist, really pretty sight while the Sun comes up over the hills.

All in all for the two nights we were there, it was good enough. We only paid the 100 dinars (less than 1 euro) entry fee to the park and that’s it. The actual camping was free, so we can’t complain about a single thing.

The hike

Saturday morning we got up a bit after 7am, had coffee and tea, some breakfast and prepared for the hike.

Senka made sandwiches and I packed the water, compass, maps and the likes for our hike. As usual we took way too much food, but the 9 liter of water was just enough. We drank more than 7 liters for the 7 hours we were out on the trail. The Sun was relentless that day.

The trail is nicely marked, it is both clearly visible and has the trail markings at regular distances. It was a bit overgown here and there, but nothing serious. It passes through, I think, two wooded parts at the beginning of the trail and after that it’s pretty much Sun all the way to the top and back. Pack sunscreen if you go in clear weather.

What we liked a lot was the fact that it wasn’t crowded. Every 30 minutes or so we would come across a group of hikers, have a short chat with them and then move along. We could enjoy the nature and the views on our own, but we still didn’t feel completely alone. Just the perfect sweet spot of “traffic” on the trail.

Apart from the hot Sun, there weren’t really any other problems with the hike. One mountain guide we came across told us that doing the hike in short pants wasn’t really smart because apparently there are snakes on the trail. Stupid from us not looking that up beforehand and preparing accordingly.

At the top of the trail there is a viewpoint from which we could appreciate the view and look at the huge scavenger birds flying around looking for food.

On our way back to the camp, we went down to the river and had a nice swim. There is one short path down from the trail to the river bank, but it is seriously overgrown and barely visible so be extra careful if you decide to do the same.

Other activities in the area

Apart from hiking, it also possible to go on a boat cruise down the river and back, with optional stops at a couple of caves to go spelunking as well as fishing. For these you’ll have to make prior arrangements with one of the guides or park rangers.

You can also try and buy some Sjenica cheese, which is sold by a household near at the top of the trail. People say it’s really delicious, but we haven’t tried it ourselves.

Happy hiking!

Tags: Griffon Vulture, Uvac, camp, camping, hike, hiking, nature, reserve.
Categories: Blablabla, Free Time.

Missing colors for PHPUnit

by Robert Basic on July 20, 2016.

I ran accross a minor issue today that I never experienced before. The colors for the PHPUnit’s output were missing. I had the colors=true directive set in the phpunit.xml configuration file, but the output was just black and white.

Turns out I was missing the posix extension, which is provided by the php-process package on Fedora. After installing it:

$ sudo dnf install php-process

all was good again in the world of unit testing.

Oh well.

Happy hackin’!

Tags: php, phpunit.
Categories: Development, Programming, Software.

Using Tactician in a Zend Expressive application

by Robert Basic on July 13, 2016.

I spent some time connecting the dots last week, so I decided to put together an example on how to get started with using Tactician in a Zend Expressive application. The example itself is not really useful, but it does show how to setup the dependencies and get started with these two libraries.

Zend Expressive is a PSR7 compatible microframework that provides interfaces for routing, DI containers, templating and error handling. It provides a couple out of the box, so you can either use those, or write your own implementations.

Tactician is a command bus library whose goal is to make using the command pattern easy to use in your applications. It allows to have an object that represents a command, pass it on to the command bus which will figure out which command handler should take care of that command.

Let’s dive in

To get up and running quickly with Zend Expressive we can create a skeleton application. It does some basic wiring for us, like setting up the routing and the DI container.

It also comes with a dummy ping action, at /api/ping, which just gives us the current unix timestamp. This example is going to expand on that and create a Ping command that will be handled by a Ping command handler. The command handler will get some additional dependencies from the container, just to make the example a bit more interesting.

Creating the skeleton application is really easy with Composer:

$ cd /var/www
$ composer create-project zendframework/zend-expressive-skeleton tactician-example

Bring in the Tactician and the tactician-container plugin as project dependencies. The tactician-container plugin allows us to lazy load command handlers from a container-interop compatible container:

$ composer require league/tactician
$ composer require league/tactician-container

Now that we have all our libraries in, let’s change how the container creates the Ping action. Before it was being just invoked by the container, but now we want to create it through a factory:

config/autoload/routes.global.php

diff --git a/config/autoload/routes.global.php b/config/autoload/routes.global.php
index 856f5ab..8335450 100644
--- a/config/autoload/routes.global.php
+++ b/config/autoload/routes.global.php
@@ -4,10 +4,10 @@ return [
     'dependencies' => [
         'invokables' => [
             Zend\Expressive\Router\RouterInterface::class => Zend\Expressive\Router\FastRouteRouter::class,
-            App\Action\PingAction::class => App\Action\PingAction::class,
         ],
         'factories' => [
             App\Action\HomePageAction::class => App\Action\HomePageFactory::class,
+            App\Action\PingAction::class => App\Action\PingFactory::class
         ],
     ],

This will allow us to pass in dependencies to the PingAction class.

The Ping action’s factory is simple:

src/App/Action/PingFactory.php

<?php

namespace App\Action;

use Interop\Container\ContainerInterface;

class PingFactory
{
    public function __invoke(ContainerInterface $container)
    {
        $commandBus = $container->get('CommandBus');

        return new PingAction($commandBus);
    }
}

We are telling the container to get the service called CommandBus and pass it as an argument to the Ping action’s constructor.

Wiring in Tactician

We haven’t yet defined the CommandBus service, so let’s do that next by telling the service manager to create the CommandBus using the App\CommandBusFactory factory:

config/autoload/dependencies.global.php

diff --git a/config/autoload/dependencies.global.php b/config/autoload/dependencies.global.php
index b2b08f5..460c045 100644
--- a/config/autoload/dependencies.global.php
+++ b/config/autoload/dependencies.global.php
@@ -19,6 +19,7 @@ return [
         'factories' => [
             Application::class => ApplicationFactory::class,
             Helper\UrlHelper::class => Helper\UrlHelperFactory::class,
+            'CommandBus' => App\CommandBusFactory::class
         ],
     ],
 ];

This factory sets up the Tactician’s command bus and is the main point of this example:

src/App/CommandBusFactory.php

<?php

namespace App;

use League\Tactician\CommandBus;
use League\Tactician\Handler\CommandHandlerMiddleware;
use League\Tactician\Container\ContainerLocator;
use League\Tactician\Handler\CommandNameExtractor\ClassNameExtractor;
use League\Tactician\Handler\MethodNameInflector\InvokeInflector;
use Interop\Container\ContainerInterface;

class CommandBusFactory
{
    public function __invoke(ContainerInterface $container)
    {
        $inflector = new InvokeInflector();

        $commandsMapping = [];
        $locator = new ContainerLocator($container, $commandsMapping);

        $nameExtractor = new ClassNameExtractor();

        $commandHandlerMiddleware = new CommandHandlerMiddleware(
            $nameExtractor,
            $locator,
            $inflector
        );

        $commandBus = new CommandBus([
            $commandHandlerMiddleware
        ]);

        return $commandBus;
    }
}

Tactician uses a command handler middleware to handle commands. That middleware in turn uses a name extractor to get the command name out of a command, a locator to find the actual command handler and an inflector to figure out the method to call on the command handler to handle the command. Tactician’s middleware system is nicely described in the documentation.

The ClassNameExtractor will extract the command name from the class name.

The ContainerLocator will use our container-interop compatible container to find the command handler, which in this example is Zend ServiceManager.

The InvokeInflector dictates that the command handler needs to have an __invoke method which will get our Ping command as an argument and then it’s up to the Ping command handler to handle the command.

The $commandsMapping array that we are passing to the locator is going to be a map of commands and their handlers. We’ll populate that later on.

In the next step, let’s tell the PingAction’s constructor to accept the command bus:

src/App/Action/PingAction.php

diff --git a/src/App/Action/PingAction.php b/src/App/Action/PingAction.php
index ea2ae22..612fb32 100644
--- a/src/App/Action/PingAction.php
+++ b/src/App/Action/PingAction.php
@@ -5,9 +5,15 @@ namespace App\Action;
 use Zend\Diactoros\Response\JsonResponse;
 use Psr\Http\Message\ResponseInterface;
 use Psr\Http\Message\ServerRequestInterface;
+use League\Tactician\CommandBus;

 class PingAction
 {
+    public function __construct(CommandBus $commandBus)
+    {
+        $this->commandBus = $commandBus;
+    }
+
     public function __invoke(ServerRequestInterface $request, ResponseInterface $response, callable $next = null)
     {
         return new JsonResponse(['ack' => time()]);

Cool, at this point we have everything set up to start sending and handling commands.

Commands and their handlers

The command we are going to create is a simple one:

src/App/Command/Ping.php

<?php

namespace App\Command;

class Ping
{
    private $commandTime;

    public function __construct()
    {
        $this->commandTime = time();
    }

    public function getCommandTime()
    {
        return $this->commandTime;
    }
}

It just sets the command time to the current unix timestamp.

Updating the PingAction to include the creation of our Ping command and passing it on to the command bus to be handled:

src/App/Action/PingAction.php

diff --git a/src/App/Action/PingAction.php b/src/App/Action/PingAction.php
index 612fb32..6cb9334 100644
--- a/src/App/Action/PingAction.php
+++ b/src/App/Action/PingAction.php
@@ -6,6 +6,7 @@ use Zend\Diactoros\Response\JsonResponse;
 use Psr\Http\Message\ResponseInterface;
 use Psr\Http\Message\ServerRequestInterface;
 use League\Tactician\CommandBus;
+use App\Command\Ping as PingCommand;

 class PingAction
 {
@@ -16,6 +17,11 @@ class PingAction

     public function __invoke(ServerRequestInterface $request, ResponseInterface $response, callable $next = null)
     {
-        return new JsonResponse(['ack' => time()]);
+        $pingCommand = new PingCommand();
+        $time = $pingCommand->getCommandTime();
+
+        $this->commandBus->handle($pingCommand);
+
+        return new JsonResponse(['ack' => $time]);
     }
 }

Now is the time to let Tactician know about our command and command handler mapping, so it knows which handler handles which command:

src/App/CommandBusFactory.php

diff --git a/src/App/CommandBusFactory.php b/src/App/CommandBusFactory.php
index ba587f6..b79fbb1 100644
--- a/src/App/CommandBusFactory.php
+++ b/src/App/CommandBusFactory.php
@@ -9,13 +9,18 @@ use League\Tactician\Handler\CommandNameExtractor\ClassNameExtractor;
 use League\Tactician\Handler\MethodNameInflector\InvokeInflector;
 use Interop\Container\ContainerInterface;

+use App\Command\Ping as PingCommand;
+use App\CommandHandler\Ping as PingCommandHandler;
+
 class CommandBusFactory
 {
     public function __invoke(ContainerInterface $container)
     {
         $inflector = new InvokeInflector();

-        $commandsMapping = [];
+        $commandsMapping = [
+            PingCommand::class => PingCommandHandler::class
+        ];
         $locator = new ContainerLocator($container, $commandsMapping);

         $nameExtractor = new ClassNameExtractor();

We’re almost there. I promise.

The command handler is going to be created through a factory, so we can inject dependencies into it:

src/App/CommandHandler/PingFactory.php

<?php

namespace App\CommandHandler;

use Interop\Container\ContainerInterface;

class PingFactory
{
    public function __invoke(ContainerInterface $container)
    {
        $logPath = '/tmp/ping-command.log';

        return new Ping($logPath);
    }
}

It doesn’t do much, it just passes a path to a log file. Of course, in real code, you’d probably pass in some dependency gotten from the container.

The command handler won’t do much either, it’s just going to log the the ping’s command time in the log file we passed in from the command handler factory:

src/App/CommandHandler/Ping.php

<?php

namespace App\CommandHandler;

use App\Command\Ping as PingCommand;

class Ping
{
    private $logPath;

    public function __construct($logPath)
    {
        $this->logPath = $logPath;
    }

    public function __invoke(PingCommand $pingCommand)
    {
        $commandTime = $pingCommand->getCommandTime();

        file_put_contents($this->logPath, $commandTime . PHP_EOL, FILE_APPEND);
    }
}

And finally let the service manager know how to create the Ping command handler:

config/autoload/dependencies.global.php

diff --git a/config/autoload/dependencies.global.php b/config/autoload/dependencies.global.php
index 460c045..2c8e3ee 100644
--- a/config/autoload/dependencies.global.php
+++ b/config/autoload/dependencies.global.php
@@ -19,7 +19,8 @@ return [
         'factories' => [
             Application::class => ApplicationFactory::class,
             Helper\UrlHelper::class => Helper\UrlHelperFactory::class,
-            'CommandBus' => App\CommandBusFactory::class
+            'CommandBus' => App\CommandBusFactory::class,
+            App\CommandHandler\Ping::class => App\CommandHandler\PingFactory::class
         ],
     ],
 ];

Navigating to /api/ping should display the {“ack”:1468171544} response, and the log file at /tmp/ping-command.log should have the same timestamp logged.

That was a lot of code

I know, looks like an awful lot of code just to log a timestamp in a file somewhere. But the point is that even for more complicated commands and handlers the basic wiring stays the same — create the CommandBus factory, set up mapping of commands and handlers and the rest is pretty much the business logic of the application.

Happy hackin’!

P.S.: I’m trying out this new way of providing code samples by using diffs, so it’s easier to follow what changed where. Let me know how it looks, thanks!

Tags: command bus, container, php, tactician, zend expressive.
Categories: Development, Programming.