MC-36456: union implementation

Author: cpartica

lib/internal/Magento/Framework/GraphQl/Config/Element/UnionFactory.php

@@ -31,7 +31,7 @@ public function __construct(
     }
 
     /**
-     * Instantiate an object representing 'interface' GraphQL config element.
+     * Instantiate an object representing 'union' GraphQL config element.
      *
      * @param array $data
      * @return ConfigElementInterface
@@ -42,11 +42,11 @@ public function createFromConfigData(array $data): ConfigElementInterface
     }
 
     /**
-     * Create interface object based off array of configured GraphQL Output/InputInterface.
+     * Create union object based off array of configured GraphQL.
      *
-     * Interface data must contain name, type resolver, and field definitions. The type resolver should point to an
-     * implementation of the TypeResolverInterface that decides what concrete GraphQL type to output. Description is
-     * the only optional field.
+     * Union data must contain name, type resolver, and possible concrete types definitions
+     * The type resolver should point to an implementation of the TypeResolverInterface
+     * that decides what concrete GraphQL type to output. Description is the only optional field.
      *
      * @param array $unionData
      * @param array $types

lib/internal/Magento/Framework/GraphQl/Config/Element/UnionInterface.php

@@ -10,7 +10,7 @@
 use Magento\Framework\GraphQl\Config\ConfigElementInterface;
 
 /**
- * Defines contracts for return type data as GraphQL objects.
+ * Defines the contract for the union configuration data type.
  */
 interface UnionInterface extends ConfigElementInterface
 {

lib/internal/Magento/Framework/GraphQl/Schema/Type/Output/ElementMapper/Formatter/ResolveType.php

@@ -38,12 +38,7 @@ public function __construct(ObjectManagerInterface $objectManager)
     public function format(ConfigElementInterface $configElement, OutputTypeInterface $outputType) : array
     {
         $config = [];
-        if ($configElement instanceof InterfaceType) {
-            $typeResolver = $this->objectManager->create($configElement->getTypeResolver());
-            $config['resolveType'] = function ($value) use ($typeResolver) {
-                return $typeResolver->resolveType($value);
-            };
-        } elseif ($configElement instanceof UnionType) {
+        if ($configElement instanceof InterfaceType || $configElement instanceof UnionType) {
             $typeResolver = $this->objectManager->create($configElement->getTypeResolver());
             $config['resolveType'] = function ($value) use ($typeResolver) {
                 return $typeResolver->resolveType($value);

lib/internal/Magento/Framework/GraphQl/Schema/Type/Output/ElementMapper/FormatterComposite.php

@@ -33,14 +33,15 @@ public function __construct(array $formatters)
      */
     public function format(ConfigElementInterface $configElement, OutputTypeInterface $outputType) : array
     {
-        $config = [
+        $defaultConfig = [
             'name' => $configElement->getName(),
             'description' => $configElement->getDescription()
         ];
+        $formattedConfig = [];
         foreach ($this->formatters as $formatter) {
-            $config = array_merge($config, $formatter->format($configElement, $outputType));
+            $formattedConfig[] = $formatter->format($configElement, $outputType);
         }
 
-        return $config;
+        return  array_merge($defaultConfig,...$formattedConfig);
     }
 }

lib/internal/Magento/Framework/GraphQl/Schema/Type/Output/OutputMapper.php

@@ -13,7 +13,7 @@
 use Magento\Framework\Phrase;
 
 /**
- * Map type names to their output type/interface/enum classes.
+ * Map type names to their output type/interface/union/enum classes.
  */
 class OutputMapper
 {

lib/internal/Magento/Framework/GraphQl/Schema/Type/Output/OutputUnionObject.php

@@ -11,7 +11,7 @@
 use Magento\Framework\GraphQl\Schema\Type\UnionType;
 
 /**
- * 'union' type compatible with GraphQL schema generator.
+ * The 'union' type compatible with GraphQL schema generator.
  */
 class OutputUnionObject extends UnionType
 {

lib/internal/Magento/Framework/GraphQlSchemaStitching/GraphQlReader.php

@@ -11,6 +11,7 @@
 use Magento\Framework\Config\FileResolverInterface;
 use Magento\Framework\Config\ReaderInterface;
 use Magento\Framework\GraphQlSchemaStitching\GraphQlReader\TypeMetaReaderInterface as TypeReaderComposite;
+use Magento\Framework\GraphQlSchemaStitching\GraphQlReader\Reader\InterfaceType;
 
 /**
  * Reads *.graphqls files from modules and combines the results as array to be used with a library to configure objects
@@ -21,10 +22,9 @@ class GraphQlReader implements ReaderInterface
 
     public const GRAPHQL_SCHEMA_FILE = 'schema.graphqls';
 
+    /** @deprecated */
     public const GRAPHQL_INTERFACE = 'graphql_interface';
 
-    public const GRAPHQL_UNION = 'graphql_union';
-
     /**
      * File locator
      *
@@ -180,7 +180,7 @@ private function parseTypes(string $graphQlSchemaContent) : array
     private function copyInterfaceFieldsToConcreteTypes(array $source): array
     {
         foreach ($source as $interface) {
-            if ($interface['type'] ?? '' == 'graphql_interface') {
+            if ($interface['type'] ?? '' == InterfaceType::GRAPHQL_INTERFACE) {
                 foreach ($source as $typeName => $type) {
                     if (isset($type['implements'])
                         && isset($type['implements'][$interface['name']])
@@ -332,7 +332,7 @@ private function addModuleNameToTypes(array $source, string $filePath): array
     {
         foreach ($source as $typeName => $type) {
             if ((!isset($type['module']))
-                && (($type['type'] ?? '' === self::GRAPHQL_INTERFACE && isset($type['typeResolver']))
+                && (($type['type'] ?? '' === InterfaceType::GRAPHQL_INTERFACE && isset($type['typeResolver']))
                     || isset($type['implements'])
                 )
             ) {

lib/internal/Magento/Framework/GraphQlSchemaStitching/GraphQlReader/Reader/EnumType.php

@@ -15,6 +15,8 @@
  */
 class EnumType implements TypeMetaReaderInterface
 {
+    public const GRAPHQL_ENUM = 'graphql_enum';
+
     /**
      * @var DocReader
      */
@@ -37,7 +39,7 @@ public function read(\GraphQL\Type\Definition\Type $typeMeta) : array
         if ($typeMeta instanceof \GraphQL\Type\Definition\EnumType) {
             $result = [
                 'name' => $typeMeta->name,
-                'type' => 'graphql_enum',
+                'type' => self::GRAPHQL_ENUM,
                 'items' => [] // Populated later
             ];
             foreach ($typeMeta->getValues() as $enumValueMeta) {

lib/internal/Magento/Framework/GraphQlSchemaStitching/GraphQlReader/Reader/InputObjectType.php

@@ -17,6 +17,8 @@
  */
 class InputObjectType implements TypeMetaReaderInterface
 {
+    public const GRAPHQL_INPUT = 'graphql_input';
+
     /**
      * @var TypeMetaWrapperReader
      */
@@ -57,7 +59,7 @@ public function read(\GraphQL\Type\Definition\Type $typeMeta) : array
             $typeName = $typeMeta->name;
             $result = [
                 'name' => $typeName,
-                'type' => 'graphql_input',
+                'type' => self::GRAPHQL_INPUT,
                 'fields' => [] // Populated later
             ];
             $fields = $typeMeta->getFields();

lib/internal/Magento/Framework/GraphQlSchemaStitching/GraphQlReader/Reader/InterfaceType.php

@@ -17,6 +17,8 @@
  */
 class InterfaceType implements TypeMetaReaderInterface
 {
+    public const GRAPHQL_INTERFACE = 'graphql_interface';
+
     /**
      * @var FieldMetaReader
      */
@@ -57,7 +59,7 @@ public function read(\GraphQL\Type\Definition\Type $typeMeta) : array
             $typeName = $typeMeta->name;
             $result = [
                 'name' => $typeName,
-                'type' => 'graphql_interface',
+                'type' => self::GRAPHQL_INTERFACE,
                 'fields' => []
             ];