Avoid long argument lists in the symfony constructor service

Question

I use Symfony to develop my web applications, but I have a problem all the time. I always get too much mess in the constructor of my services, because I want to be able to unit test my services correctly.

Theoretical use case

Let's say I need a service that allows me to process an XML file and save its contents in a database.

<?xml version="1.0" encoding="UTF-8" ?>
<users>
    <user>
        <id>1234</id>
        <username>Example User</username>
        <email>[e-mail]</email>
        <usergroup>
            <id>567</id>
            <name>Example User Group</name>
        </usergroup>
        <permissions>
            <item>ALLOWED_TO_CREATE</item>
            <item>ALLOWED_TO_UPDATE</item>
            <item>ALLOWED_TO_DELETE</item>
            <item>ALLOWED_TO_view</item>
        </permissions>
    </user>
</users>

Already comes a lot of things that you need to enter into this service:

• DomCrawler (for reading an XML file)
• UserRepository (to get existing users)
• UserGroupRepository (to get existing user groups)
• PermissionsRepository (to obtain existing permissions)
• EntityManager (to save en flush new / updated objects)

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1: Doctrine

Doctrine $doctrine->getRepository(User::class)

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2:

services.yml

services:
  AppBundle\Service\MyImportService:
    calls:
      - [setUserRepository, ['@app.user_repository']]

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, unit test?

?

Answer 1

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