Updated blog example: demonstrated and commented inheritance vs composition options; added describing comments

examples/01-blog/Blog/AppContext.php

@@ -7,7 +7,7 @@ use GraphQL\Utils;
 
 /**
  * Class AppContext
- * Instance available in all GraphQL resolvers
+ * Instance available in all GraphQL resolvers as 3rd argument
  *
  * @package GraphQL\Examples\Social
  */

examples/01-blog/Blog/Type/BaseType.php

@@ -4,8 +4,11 @@ namespace GraphQL\Examples\Blog\Type;
 use GraphQL\Type\Definition\Type;
 use GraphQL\Type\DefinitionContainer;
 
-class BaseType implements DefinitionContainer
+abstract class BaseType implements DefinitionContainer
 {
+    // Base class to reduce boilerplate for those who prefer own clean hierarchy of classes
+    // (and avoids extending GraphQL classes directly)
+
     /**
      * @var Type
      */

examples/01-blog/Blog/Type/CommentType.php

@@ -11,6 +11,7 @@ class CommentType extends BaseType
 {
     public function __construct(TypeSystem $types)
     {
+        // Option #1: using composition over inheritance to define type, see ImageType for inheritance example
         $this->definition = new ObjectType([
             'name' => 'Comment',
             'fields' => function() use ($types) {
@@ -18,6 +19,7 @@ class CommentType extends BaseType
                     'id' => $types->id(),
                     'author' => $types->user(),
                     'parent' => $types->comment(),
+                    'isAnonymous' => $types->boolean(),
                     'replies' => [
                         'type' => $types->listOf($types->comment()),
                         'args' => [
@@ -45,6 +47,9 @@ class CommentType extends BaseType
 
     public function author(Comment $comment, $args, AppContext $context)
     {
+        if ($comment->isAnonymous) {
+            return null;
+        }
         return $context->dataSource->findUser($comment->authorId);
     }
 

examples/01-blog/Blog/Type/Enum/ContentFormatEnum.php

@@ -11,6 +11,7 @@ class ContentFormatEnum extends BaseType
 
     public function __construct()
     {
+        // Option #1: Define type using composition over inheritance, see ImageSizeEnumType for inheritance option
         $this->definition = new EnumType([
             'name' => 'ContentFormatEnum',
             'values' => [self::FORMAT_TEXT, self::FORMAT_HTML]

examples/01-blog/Blog/Type/Enum/ImageSizeEnumType.php

@@ -2,24 +2,23 @@
 namespace GraphQL\Examples\Blog\Type\Enum;
 
 use GraphQL\Examples\Blog\Data\Image;
-use GraphQL\Examples\Blog\Type\BaseType;
 use GraphQL\Type\Definition\EnumType;
 
-class ImageSizeEnumType extends BaseType
+class ImageSizeEnumType extends EnumType
 {
-    /**
-     * ImageSizeEnumType constructor.
-     */
     public function __construct()
     {
-        $this->definition = new EnumType([
+        // Option #2: Define enum type using inheritance
-            'name' => 'ImageSizeEnum',
+        $config = [
+            // Note: 'name' option is not needed in this form - it will be inferred from className
             'values' => [
                 'ICON' => Image::SIZE_ICON,
                 'SMALL' => Image::SIZE_SMALL,
                 'MEDIUM' => Image::SIZE_MEDIUM,
                 'ORIGINAL' => Image::SIZE_ORIGINAL
             ]
-        ]);
+        ];
+
+        parent::__construct($config);
     }
 }

examples/01-blog/Blog/Type/Field/HtmlField.php

@@ -10,6 +10,9 @@ class HtmlField
     {
         $objectKey = $objectKey ?: $name;
 
+        // Demonstrates how to organize re-usable fields
+        // Usual example: when the same field with same args shows up in different types
+        // (for example when it is a part of some interface)
         return [
             'name' => $name,
             'type' => $types->string(),

examples/01-blog/Blog/Type/FieldDefinitions.php

@@ -1,31 +0,0 @@
-<?php
-namespace GraphQL\Examples\Blog\Type;
-
-
-use GraphQL\Examples\Blog\Type\Enum\ContentFormatEnum;
-use GraphQL\Examples\Blog\TypeSystem;
-
-/**
- * Class Field
- * @package GraphQL\Examples\Blog\Type
- */
-class FieldDefinitions
-{
-    private $types;
-
-    public function __construct(TypeSystem $types)
-    {
-        $this->types = $types;
-    }
-
-    private $htmlField;
-
-    public function htmlField($name, $objectKey = null)
-    {
-        $objectKey = $objectKey ?: $name;
-
-        return $this->htmlField ?: $this->htmlField = [
-            'name' => $name,
-        ];
-    }
-}

examples/01-blog/Blog/Type/ImageType.php

@@ -7,11 +7,12 @@ use GraphQL\Examples\Blog\TypeSystem;
 use GraphQL\Type\Definition\EnumType;
 use GraphQL\Type\Definition\ObjectType;
 
-class ImageType extends BaseType
+class ImageType extends ObjectType
 {
     public function __construct(TypeSystem $types)
     {
-        $this->definition = new ObjectType([
+        // Option #2: define type using inheritance, see any other object type for compositional example
+        $config = [
             'name' => 'ImageType',
             'fields' => [
                 'id' => $types->id(),
@@ -43,7 +44,9 @@ class ImageType extends BaseType
                     }
                 ]
             ]
-        ]);
+        ];
+
+        parent::__construct($config);
     }
 
     public function resolveUrl(Image $value, $args, AppContext $context)

examples/01-blog/Blog/Type/MentionType.php

@@ -11,6 +11,7 @@ class MentionType extends BaseType
 {
     public function __construct(TypeSystem $types)
     {
+        // Option #1: using composition over inheritance to define type, see ImageType for inheritance example
         $this->definition = new UnionType([
             'name' => 'Mention',
             'types' => function() use ($types) {

examples/01-blog/Blog/Type/NodeType.php

@@ -9,12 +9,9 @@ use GraphQL\Type\Definition\InterfaceType;
 
 class NodeType extends BaseType
 {
-    /**
-     * NodeType constructor.
-     * @param TypeSystem $types
-     */
     public function __construct(TypeSystem $types)
     {
+        // Option #1: using composition over inheritance to define type, see ImageType for inheritance example
         $this->definition = new InterfaceType([
             'name' => 'Node',
             'fields' => [

examples/01-blog/Blog/Type/QueryType.php

@@ -11,6 +11,7 @@ class QueryType extends BaseType
 {
     public function __construct(TypeSystem $types)
     {
+        // Option #1: using composition over inheritance to define type, see ImageType for inheritance example
         $this->definition = new ObjectType([
             'name' => 'Query',
             'fields' => [

examples/01-blog/Blog/Type/Scalar/EmailType.php

@@ -10,6 +10,7 @@ class EmailType extends BaseType
 {
     public function __construct()
     {
+        // Option #1: define scalar types using composition (see UrlType fo option #2 using inheritance)
         $this->definition = new CustomScalarType([
             'name' => 'Email',
             'serialize' => [$this, 'serialize'],

examples/01-blog/Blog/Type/Scalar/UrlType.php

@@ -5,14 +5,9 @@ use GraphQL\Language\AST\StringValue;
 use GraphQL\Type\Definition\ScalarType;
 use GraphQL\Utils;
 
-/**
+class UrlType extends ScalarType
- * Class UrlTypeDefinition
- *
- * @package GraphQL\Examples\Blog\Type\Scalar
- */
-class UrlTypeDefinition extends ScalarType
 {
-    public $name = 'Url';
+    // Option #2: Displays scalar type defined using inheritance. See EmailType for definition via composition
 
     /**
      * Serializes an internal value to include in a response.

examples/01-blog/Blog/Type/StoryType.php

@@ -23,6 +23,7 @@ class StoryType extends BaseType
 
     public function __construct(TypeSystem $types)
     {
+        // Option #1: using composition over inheritance to define type, see ImageType for inheritance example
         $this->definition = new ObjectType([
             'name' => 'Story',
             'fields' => function() use ($types) {

examples/01-blog/Blog/Type/UserType.php

@@ -11,6 +11,7 @@ class UserType extends BaseType
 {
     public function __construct(TypeSystem $types)
     {
+        // Option #1: using composition over inheritance to define type, see ImageType for inheritance example
         $this->definition = new ObjectType([
             'name' => 'User',
             'fields' => function() use ($types) {

examples/01-blog/Blog/TypeSystem.php

@@ -5,13 +5,12 @@ use GraphQL\Examples\Blog\Type\CommentType;
 use GraphQL\Examples\Blog\Type\Enum\ContentFormatEnum;
 use GraphQL\Examples\Blog\Type\Enum\ImageSizeEnumType;
 use GraphQL\Examples\Blog\Type\Field\HtmlField;
-use GraphQL\Examples\Blog\Type\FieldDefinitions;
 use GraphQL\Examples\Blog\Type\MentionType;
 use GraphQL\Examples\Blog\Type\NodeType;
 use GraphQL\Examples\Blog\Type\QueryType;
 use GraphQL\Examples\Blog\Type\Scalar\EmailType;
 use GraphQL\Examples\Blog\Type\StoryType;
-use GraphQL\Examples\Blog\Type\Scalar\UrlTypeDefinition;
+use GraphQL\Examples\Blog\Type\Scalar\UrlType;
 use GraphQL\Examples\Blog\Type\UserType;
 use GraphQL\Examples\Blog\Type\ImageType;
 use GraphQL\Type\Definition\ListOfType;
@@ -129,15 +128,15 @@ class TypeSystem
 
     public function email()
     {
-        return $this->emailType ?: ($this->emailType = new EmailType);
+        return $this->emailType ?: ($this->emailType = new EmailType());
     }
 
     /**
-     * @return UrlTypeDefinition
+     * @return UrlType
      */
     public function url()
     {
-        return $this->urlType ?: ($this->urlType = new UrlTypeDefinition);
+        return $this->urlType ?: ($this->urlType = new UrlType());
     }
 
     /**