4.6 API Platform Migration

If your API resources are defined via PHP attributes only, you can skip this step. For XML/YAML resource definitions, migrate to the new Metadata format used by API Platform 4.

1. XML: update namespace & XSD

Before:

<resources xmlns="https://api-platform.com/schema/metadata"
           xsi:schemaLocation="https://api-platform.com/schema/metadata https://api-platform.com/schema/metadata/metadata-2.0.xsd"
           xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">

After:

<resources xmlns="https://api-platform.com/schema/metadata/resources-3.0"
           xsi:schemaLocation="https://api-platform.com/schema/metadata/resources-3.0 https://api-platform.com/schema/metadata/resources-3.0/resources-3.0.xsd"
           xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">

2. Convert operations structure (unify to operations)

API Platform 3/4 uses a single operations node and Metadata classes (ApiPlatform\Metadata\Get, GetCollection, Post, Put, Patch, Delete). HTTP method is implied by the class; custom paths use uriTemplate.

XML — from collectionOperations/itemOperations → operations

Before:

<resource class="Plugin\Entity\Term" shortName="Term">
  <collectionOperations>
    <collectionOperation name="get" />
    <collectionOperation name="post">
      <attribute name="path">/plugin/terms</attribute>
    </collectionOperation>
  </collectionOperations>
  <itemOperations>
    <itemOperation name="get" />
    <itemOperation name="put" />
  </itemOperations>
</resource>

After:

<resource class="Plugin\Entity\Term" shortName="Term">
  <operations>
    <operation name="plugin_terms_get_collection"
               class="ApiPlatform\Metadata\GetCollection"
               uriTemplate="/plugin/terms" />
    <operation name="plugin_terms_post"
               class="ApiPlatform\Metadata\Post"
               uriTemplate="/plugin/terms" />
    <operation name="plugin_terms_get"
               class="ApiPlatform\Metadata\Get"
               uriTemplate="/plugin/terms/{id}" />
    <operation name="plugin_terms_put"
               class="ApiPlatform\Metadata\Put"
               uriTemplate="/plugin/terms/{id}" />
  </operations>
</resource>

3. Providers / processors (only if you use them)

If you referenced custom providers/persisters before, align them with the state provider/processor model.