Services, Autowiring & Pushing To GitHub

We now have a fully-functional new class with a test! But, we have not registered this class as a service yet. Which means... the user would still need to do that manually. That's a bummer!

Adding the Service Config

Inside SecurityBundle, look at DependencyInjection and open SecurityExtension.php. This class loads several XML files that provide all of the services for this bundle. Inside the Resources/config/ directory, open security.xml. Around line 136... yep! You'll see the services that our new service depends on - like FirewallMap and FirewallConfig:

<?xml version="1.0" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://symfony.com/schema/dic/services http://symfony.com/schema/dic/services/services-1.0.xsd">
... lines 6 - 12
<services>
... lines 14 - 135
<service id="security.firewall.map" class="Symfony\Bundle\SecurityBundle\Security\FirewallMap">
<argument /> <!-- Firewall context locator -->
<argument /> <!-- Request matchers -->
</service>
... lines 140 - 147
<service id="security.firewall.config" class="Symfony\Bundle\SecurityBundle\Security\FirewallConfig" abstract="true">
<argument /> <!-- name -->
<argument /> <!-- user_checker -->
<argument /> <!-- request_matcher -->
<argument /> <!-- security enabled -->
<argument /> <!-- stateless -->
<argument /> <!-- provider -->
<argument /> <!-- context -->
<argument /> <!-- entry_point -->
<argument /> <!-- access_denied_handler -->
<argument /> <!-- access_denied_url -->
<argument type="collection" /> <!-- listeners -->
<argument /> <!-- switch_user -->
</service>
... lines 162 - 223
</services>
</container>

To register our new TargetPathHelper as a service, we could include some XML config in any of these XML files: it doesn't technically matter. But, which file makes the most sense? Well, 1 minute ago, I wasn't sure. But now that I see all of these related services, I think we've already found the right place. If we're wrong, someone will tell us when we create the PR.

Add a new service tag. For the id, how about, security.target_path_helper. I'm trying to follow the existing naming conventions in this file.

For the class, it's Symfony, well, let's cheat: copy the namespace from the class above, paste, then TargetPathHelper:

<?xml version="1.0" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://symfony.com/schema/dic/services http://symfony.com/schema/dic/services/services-1.0.xsd">
... lines 6 - 12
<services>
... lines 14 - 162
<service id="security.target_path_helper" class="Symfony\Bundle\SecurityBundle\Security\TargetPathHelper">
... lines 164 - 166
</service>
... lines 168 - 223
</services>
</container>

Inside, our service will need 3 arguments: the session, firewall map & request stack.

Add <argument type="service" id="session" />. Next, <argument type="service" id="" The id for the firewall map is up here: security.firewall.map. Finally, <argument type="service" id="request_stack" />:

<?xml version="1.0" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://symfony.com/schema/dic/services http://symfony.com/schema/dic/services/services-1.0.xsd">
... lines 6 - 12
<services>
... lines 14 - 162
<service id="security.target_path_helper" class="Symfony\Bundle\SecurityBundle\Security\TargetPathHelper">
<argument type="service" id="session" />
<argument type="service" id="security.firewall.map" />
<argument type="service" id="request_stack" />
</service>
... lines 168 - 223
</services>
</container>

Done! Our new class is now registered as a service!

But... there's still one small thing missing with this service. To allow TargetPathHelper to be autowired, like FirewallMap in the issue example, we need to create an alias from that class to the service id - just like in the comment below.

Enabling Autowiring

To do this, add <service id="" />, go copy the class name, and paste it here. Then, alias="", copy the service id this time, and paste again:

<?xml version="1.0" ?>
<container xmlns="http://symfony.com/schema/dic/services"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://symfony.com/schema/dic/services http://symfony.com/schema/dic/services/services-1.0.xsd">
... lines 6 - 12
<services>
... lines 14 - 167
<service id="Symfony\Bundle\SecurityBundle\Security\TargetPathHelper" alias="security.target_path_helper" />
... lines 169 - 223
</services>
</container>

That's it! The TargetPathHelper will now be an autowireable service.

And... we're done! The last thing I'd recommend is to create a real project and test your new feature manually. Sure, our class has a test... but there is not a test for our service config: if we have a typo on the class name, we wouldn't know!

However, because we already went through the process earlier when testing Colin's PR, I'll skip it. But, saying you tested your code in a real app can definitely help push your PR forward.

Hey! We're done with all the hard work! Let's push our code to GitHub!

Pushing your Fork

Head over to the terminal that's in the symfony/ directory and run:

git status

No surprises! Add everything and then commit with a nice message that briefly describes what we're doing:

git add .
git commit -m "Adding a new TargetPathHelper class and service"

Cool!

git remote

Right now, we have two remotes: colinodell & origin, which is the main symfony/symfony. But, of course, we don't have access to push directly to origin. Actually, that's great - that sounds like way too much responsibility to me.

Instead of pushing directly to Symfony, we need to fork the repository. Click "Fork" and either create a new fork, or, if you already have a fork like me, click into it. Here we are: weaverryan/symfony.

Next, click "Clone or download", copy the URL, then move back over to the terminal to add this as a new remote: git remote add weaverryan and then paste:

git remote add weaverryan git@github.com:weaverryan/symfony.git

Awesome! Now we can push. The branch we created is called target-path-helper. So:

git push weaverryan target-path-helper

Back to GitHub! If you're lucky, you'll see a little yellow banner about your new branch. This banner doesn't always show up, so if it doesn't, you can refresh, find the target-path-helper branch and click "New pull request".

Next, let's fill this in & learn about Symfony's continuous integration system and the famous... fabbot!

Leave a comment!