It's possible to lazy-load a service in Symfony, but:
Is it possible to make it the default way to load services
without having to configure it for all service?
Is there a possibility to annotate a service for lazy-loading?
Regarding the lazy loading. There are multiple ways you can solve this:
For one there is the new Service Locator that was introduced in 3.3. The documentation explicitly says:
Sometimes, a service needs access to several other services without being sure that all of them will actually be used. In those cases, you may want the instantiation of the services to be lazy. However, that's not possible using the explicit dependency injection since services are not all meant to be lazy (see Lazy Services).
The referenced article on Lazy Service describes another way to solve this which requires an additional dependency ocramius/proxy-manager which will then make it possible to mark services as lazy: true in your DI config.
I don't know if I understand the first question correctly, but if you don't want to manually configure dependencies you can rely on the autowiring feature that also received major changes in Symfony 3.3 and 3.4. You can only make the autowring a default per configuration file, but using the PSR-4 autodiscovery can basically autowire your whol src directory if you want to with some manual intervention, e.g. for parameters.
Related
I'm trying to make vatin-bundle compatible with Symfony 6.
But the tests fail
The "validator" service or alias has been removed or inlined when the container was compiled. You should either make it public, or stop using the container directly and use dependency injection instead.
It seems this is new in Symfony 6
The container in static::getContainer() is actually a special test container. It gives you access to both the public services and the non-removed private services services.
What is the preferred way to make validator available in tests again?
The only way I found is creating my own alias like
services:
myvalidator:
alias: validator
public: true
and use the new alias. Is there a better way?
If the service is removed, then it's no longer accessible no matter what. It's not a matter of visibility, the service is no longer there. So you need to prevent the service from being removed: creating an alias is the best and simplest way to go about it.
This has been confirmed by maintainers here.
You can create the alias only during testing, and still access the original service. (e.g. ->get('validator'). Once the alias is created, the original service is no longer removed.
I don't think this is something really new in Symfony 6, but it's bee a thing since Symfony 4.4. Although it's true that now on Symfony 6, since it's removes previously deprecated behaviour, things could have changed.
So I've created a new Symfony 4.1 project last week and have been working on it without any issues. Until yesterday when I started using some third party dependencies. I installed the Guzzle Client by using the composer require guzzlehttp/guzzle. This installed the package just fine as far as I can see.
However, when I then try to inject this service into a constructor in my code (an event or command), I get the error message: Cannot autowire service "App\xxx\Command\testCommand": argument "$client" of method "__construct()" references class "GuzzleHttp\Client" but no such service exists.
The Guzzle service is not the only one that doesn't work, this is just an example. The weird thing to me is that there are a lot of dependencies that I have that work just fine like the Doctrine DocumentManager, JMS serializer and NelmioApiDocBundle.
What I've tried so far (and actually semi-solves the problem) is adding the service name to my services.yaml file:
services:
# default configuration for services in *this* file
_defaults:
autowire: true # Automatically injects dependencies in your services.
autoconfigure: true # Automatically registers your services as commands, event subscribers, etc.
public: false # Allows optimizing the container by removing unused services; this also means
# fetching services directly from the container via $container->get() won't work.
# The best practice is to be explicit about your dependencies anyway.
GuzzleHttp\Client: <-- Adding this makes it work flawlessly.
The problem I have with this solution is that I would end up adding hundreds of services to my services.yaml file just to get them to work. It seems to me like this is not the optimal solution.
So my question is how I could resolve this in the most elegant way. Is this something I'm doing wrong in my project? Is it something that has to be resolved on the vendors side? And if so, how could it be made to work with Symfony 4.1?
composer require GuzzleHttp\Client
It seems like you are trying to require a class, not a package. I was not aware composer is smart enough to recognize a package by it's provided classes, so I checked... it can't, only gives package name suggestions.
Make sure you understand what is a composer package.
The Guzzle service is not the only one that doesn't work, this is just an example.
You don't have a Guzzle service. You only have the guzzle library with it's classes. Services require a service definition, like the one you wrote.
The other services like Doctrine you mentioned are working, because they are bundles, which provide service definitions.
Either you use a bundle, or you use a library, and hook it up yourself.
In the case of guzzle, I would not use a bundle. Then again, I would not use guzzle directly anymore, but HTTPlug. (bundle: https://github.com/php-http/HttplugBundle, library: https://github.com/php-http/httplug)
In my case, I just needed to re-generate the optimized autoload files.
So using composer dump-autoload solved the issue for me.
Is there a nice way in Symfony 2 or 3 to load all classes within a directory that implements a particular interface?
Since Symfony 3.3/3.4 it is possible by using configuration only (without a need to write custom CompilerPass):
# config/services.yaml
services:
# ...
_instanceof:
App\HandlerInterface:
tags: ['app.handler']
App\HandlerCollection:
# inject all services tagged with app.handler as first argument
arguments: [!tagged app.handler]
and if you need to restrict services to register from a single directory see importing with resource
references:
https://symfony.com/doc/current/service_container/3.3-di-changes.html#auto-configure-with-instanceof
https://symfony.com/doc/3.4/service_container/tags.html#reference-tagged-services
http://symfony.com/doc/3.4/service_container.html#importing-many-services-at-once-with-resource
Short answer is: you can't.
You don't know, what is in a file until you load it.
Long answer (taking into account what you have wrote in the comment under the question):
The only thing you know before you load a file is its name. So one of solution is to name your modules' classes (and files) with a fixed pattern like UserModule, ProductModule and so on. That way you can load all modules by their names. But this is the solution that I wouldn't suggest.
I my opinion you should change the approach and inverse the workflow. Create a class in which you will define all modules that need to be loaded. In Symfony it's called by default AppKernel, in which you define bundles (modules) to be loaded and initialized.
This has a few advantages.
You can have multiple entry points to your application and configure each one with different modules.
You may have a few different environments (like production and development) with different modules loaded in both of them. (e.g. add some modules in development like profiler)
Also dependency managment is much easier, since you can load defined modules and add their dependencies also with autoloading.
In general I think that you should avoid manual loading any php files (except autoload.php or similar that contains autoloaders) at all.
is it possible overwrite/extend Symfony\Component\DependencyInjection\Container::get() method? I want automatic creating service, when it is not contain in container, but class of service exists.
For example:
Name of service is My.MyBundle.Model.FooRepository
Service with this name doesnt exists, but when i call:
$container->get('My.MyBundle.Model.FooRepository');
check class_exists for \My\MyBundle\Model\FooRepository and when its exists, add to container and return it. Dependencies of this new services will be resolve by kutny/autowiring-bundle.
This feature can be extended only for some namespaces or interfaces and in production enviroment can be cached, but for developing will be great helper.
Any idea?
This is not directly answering your question but maybe it's answering your need: if you want to have "auto-wiring" inside your Symfony project, you can use PHP-DI inside Symfony. PHP-DI is an alternative container that can do auto-wiring (which Symfony does not).
Have a look at the Symfony 2 integration documentation to see if it can fit your bill.
I am having a hard time understanding Symfony2 services. I have read lots of stuff everywhere (including some here in SO) but none seems to fully explain it.
Suppose I have a bundle A and a separated bundle B. I want B functionality available to the A bundle. I want to inject B in the service container so A will be able to use it.
Which bundle should have a Services directory? Which one should have a configuration file? Both if needed? And where the Extension goes? Why?
Bundle B will require an Extension in order to load it's services.xml file.
Bundle B will require an entry in it's services.xml file to define the service.
Bundle B will have the Services directory containing your service class which exposes the desired functionality.
Bundle A does not require anything special. It will be able to use the container to access the service exposed by Bundle B. Just needs to know the service id.
It's confusing until you make a few services.
Read these two questions and my answers to them first:
Symfony2 conceptual issue: general bundles vs. specific ones,
Should everything really be a bundle in Symfony 2?
Assuming you're talking about app specific bundles, I suggest having one bundle only and keep services out it. Then, you could register your services in several ways:
Directly in the config.yml,
Creating an extension class in your AppBundle, or
Via annotations from JMSDiExtraBundle — this is what I prefer personally.