fix: swagger post param item

Author: soyuka

src/Core/Swagger/Serializer/DocumentationNormalizer.php

@@ -582,7 +582,6 @@ private function updatePostOperation(bool $v3, \ArrayObject $pathOperation, arra
         $identifiers = (array) $resourceMetadata
                 ->getTypedOperationAttribute($operationType, $operationName, 'identifiers', [], false);
 
-        $operationType = $identifiers ? $operationType : OperationType::COLLECTION;
         $pathOperation = $this->addItemOperationParameters($v3, $pathOperation, $operationType, $operationName, $resourceMetadata, $resourceClass);
 
         $successResponse = ['description' => sprintf('%s resource created', $resourceShortName)];
@@ -682,6 +681,12 @@ private function addItemOperationParameters(bool $v3, \ArrayObject $pathOperatio
         $identifiers = (array) $resourceMetadata
                 ->getTypedOperationAttribute($operationType, $operationName, 'identifiers', [], false);
 
+        // Auto-generated routes in API Platform < 2.7 are considered as collection, hotfix this as the OpenApi Factory supports new operations anyways.
+        // this also fixes a bug where we could not create POST item operations in API P 2.6
+        if (OperationType::ITEM === $operationType && 'post' === substr($operationName, -4)) {
+            $operationType = OperationType::COLLECTION;
+        }
+
         if (!$identifiers && OperationType::COLLECTION !== $operationType) {
             try {
                 $identifiers = $this->identifiersExtractor->getIdentifiersFromResourceClass($resourceClass);