Refactor XML loaders and various quality fixes

[dunglas]

Q	A
Bug fix?	no
New feature?	no
BC breaks?	no
Deprecations?	no
Tests pass?	yes
Fixed tickets	n/a
License	MIT
Doc PR	todo

• fix various quality problems
• rely on symfony/config for XML parsing
• decrease the complexity of XML parsers
• fix the XML schema (it can be simplified a lot and currently doesn't allow some possibilities offered by other formats).

[dunglas]

I rewrote the XML Schema. The new format looks like:

<?xml version="1.0" encoding="UTF-8" ?>

<resources>
    <resource class="ApiPlatform\Core\Tests\Fixtures\TestBundle\Entity\Dummy"/>
    <resource
            class="ApiPlatform\Core\Tests\Fixtures\TestBundle\Entity\FileConfigDummy"
            shortName="thedummyshortname"
            description="Dummy resource"
            iri="someirischema"
    >
        <itemOperation name="my_op_name">
            <attribute name="method">GET</attribute>
        </itemOperation>
        <itemOperation name="my_other_op_name">
            <attribute name="method">POST</attribute>
        </itemOperation>

        <collectionOperation name="my_collection_op">
            <attribute name="method">POST</attribute>
            <attribute name="path">the/collection/path</attribute>
        </collectionOperation>

        <attribute name="normalization_context">
            <attribute name="groups">
                <attribute>default</attribute>
            </attribute>
        </attribute>
        <attribute name="denormalization_context">
            <attribute name="groups">
                <attribute>default</attribute>
            </attribute>
        </attribute>
        <attribute name="hydra_context">
            <attribute name="@type">hydra:Operation</attribute>
            <attribute name="@hydra:title">File config Dummy</attribute>
        </attribute>
    </resource>
</resources>

WDYT @soyuka?

[soyuka]

Why are we adding empty contruct functions?

[dunglas]

The constructor is private. It's to block the possibility of initializing this class (it should only conain static methods).

[theofidry]

\o/

[soyuka]

Great improvements!! 👍

[teohhanhui]

👍

[teohhanhui]

😉