Configuring DI Container

Overview of configuration options for the Nette DI container.

Configuration File

Nette DI container is easy to control using configuration files. They are usually written in NEON format. We recommend to use editors with support for this format for editing.

 decorator: 	Decorator
 di: 			DI Container
 extensions: 	Install additional DI extensions
 includes: 	Including files
 parameters: 	Parameters
 search: 		Automatic service registration
 services: 		Services

To write a string containing the character %, you must escape it by doubling it to %%.

Parameters

You can define parameters that can then be used as part of service definitions. This can help to separate out values that you will want to change more regularly.

parameters:
	dsn: 'mysql:host=127.0.0.1;dbname=test'
	user: root
	password: secret

You can refer to foo parameter via %foo% elsewhere in any config file. They can also be used inside strings like '%wwwDir%/images'.

Parameters do not need to be just strings, they can also be array values:

parameters:
	mailer:
		host: smtp.example.com
		secure: ssl
		user: franta@gmail.com
	languages: [cs, en, de]

You can refer to single key as %mailer.user%.

If you need to get the value of any parameter in your code, for example in your class, then pass it to this class. For example, in the constructor. There is no global configuration object which can classes query for parameter values. This would be against to the principle of dependency injection.

Services

See separate chapter.

Decorator

How to bulk edit all services of a certain type? Need to call a certain method for all presenters inheriting from a particular common ancestor? That's where the decorator comes from.

decorator:
	# for all services that are instances of this class or interface
	App\Presentation\BasePresenter:
		setup:
			- setProjectId(10)       # call this method
			- $absoluteUrls = true   # and set the variable

Decorator can also be used to set tags or turn on inject mode.

decorator:
	InjectableInterface:
		tags: [mytag: 1]
		inject: true

DI

Technical settings of the DI container.

di:
	# shows DIC in Tracy Bar?
	debugger: ...        # (bool) defaults to true

	# parameter types that you never autowire
	excluded: ...        # (string[])

	# enable lazy service creation?
	lazy: ...            # (bool) default is false

	# the class from which the DI container inherits
	parentClass: ...     # (string) defaults to Nette\DI\Container

Lazy Services

Setting lazy: true enables lazy (deferred) creation of services. This means that services are not actually created when requested from the DI container, but only upon their first usage. This can speed up application startup and reduce memory usage since only the services required for a specific request are created.

For a specific service, lazy creation can be adjusted.

Lazy objects can only be used for user-defined classes, not for internal PHP classes. It requires PHP 8.4 or newer.

Metadata Export

The DI container class also contains a lot of metadata. You can reduce it by reducing the metadata export.

di:
	export:
		# to export parameters?
		parameters: false   # (bool) defaults to true

		# export tags and which ones?
		tags:               # (string[]|bool) the default is all
			- event.subscriber

		# export data for autowiring and which?
		types:              # (string[]|bool) the default is all
			- Nette\Database\Connection
			- Symfony\Component\Console\Application

If you don't use the $container->getParameters() array, you can disable parameter export. Furthermore, you can export only those tags through which you get services using the $container->findByTag(...) method. If you don't call the method at all, you can completely disable tag export with false.

You can significantly reduce the metadata for autowiring by specifying the classes you use as a parameter to the $container->getByType() method. And again, if you don't call the method at all (or only in bootstrap to get Nette\Application\Application), you can disable the export entirely with false.

Extensions

Registration of other DI extensions. In this way we add, for example, DI extension Dibi\Bridges\Nette\DibiExtension22 under the name dibi:

extensions:
	dibi: Dibi\Bridges\Nette\DibiExtension22

Then we configure it in it's section called also dibi:

dibi:
	host: localhost

You can also add a extension class with parameters:

extensions:
	application: Nette\Bridges\ApplicationDI\ApplicationExtension(%debugMode%, %appDir%, %tempDir%/cache)

Including Files

Additional configuration files can be inserted in the includes section:

includes:
	- parameters.php
	- services.neon
	- presenters.neon

The name parameters.php is not a typo, the configuration can also be written in a PHP file, which returns it as an array:

<?php
return [
	'database' => [
		'main' => [
			'dsn' => 'sqlite::memory:',
		],
	],
];

If items with the same keys appear within configuration files, they will be overwritten or merged in the case of arrays. Later included file has a higher priority than the previous one. The file in which the includes section is listed has a higher priority than the files included in it.

The automatic adding of services to the DI container makes work extremely pleasant. Nette automatically adds presenters to the container, but you can easily add any other classes.

Just specify in which directories (and subdirectories) the classes should be search for:

search:
	-	in: %appDir%/Forms
	-	in: %appDir%/Model

Usually, however, we don't want to add all the classes and interfaces, so we can filter them:

search:
	-	in: %appDir%/Forms

		# filtering by file name (string|string[])
		files:
			- *Factory.php

		# filtering by class name (string|string[])
		classes:
			- *Factory

Or we can select classes that inherit or implement at least one of the following classes:

search:
	-	in: %appDir%
		extends:
			- App\*Form
		implements:
			- App\*FormInterface

You can also define negative rules, ie class name masks or ancestors and if they comply, the service will not be added to the DI container:

search:
	-	in: %appDir%
		exclude:
			files: ...
			classes: ...
			extends: ...
			implements: ...

Tags can be set for added services:

search:
	-	in: %appDir%
		tags: ...

Merging

If items with the same keys appear in more configuration files, they will be overwritten or merged in the case of arrays. The later included file has a higher priority.

config1.neon config2.neon result 
items:
	- 1
	- 2

items:
	- 3

items:
	- 1
	- 2
	- 3

To prevent merging of a certain array use exclamation mark right after the name of the array:

config1.neon config2.neon result 
items:
	- 1
	- 2

items!:
	- 3

items:
	- 3
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  3. Configuring DI Container
version: 3.x 2.x