Add examples/05-using-typeConfigDecorator-with-SDL (#1702)

Author: Mohammed-Lashein

CHANGELOG.md

@@ -9,6 +9,10 @@ You can find and compare releases at the [GitHub release page](https://github.co
 
 ## Unreleased
 
+### Added
+  - Add **examples/05-using-typeConfigDecorator-with-SDL** to provide a solid example about resolving
+  fields on using [SDL](https://webonyx.github.io/graphql-php/schema-definition-language/) instead of [Object Types](https://webonyx.github.io/graphql-php/type-definitions/object-types/). 
+
 ## v15.20.0
 
 ### Added

docs/schema-definition-language.md

@@ -53,6 +53,8 @@ $contents = file_get_contents('schema.graphql');
 $schema = BuildSchema::build($contents, $typeConfigDecorator);
 ```
 
+You can learn more about using `$typeConfigDecorator` in [examples/05-using-typeConfigDecorator-with-SDL](../examples/05-using-typeConfigDecorator-with-SDL/)
+
 ## Performance considerations
 
 Method **BuildSchema::build()** produces a [lazy schema](schema-definition.md#lazy-loading-of-types) automatically,

examples/05-using-typeConfigDecorator-with-SDL/README.md

@@ -0,0 +1,32 @@
+# Using typeConfigDecoration with SDL
+
+This example is intended to show you the boilerplate that you would need to resolve object types in a query using the SDL instead of defining the schema using the Object Types. 
+
+**Code Context:** The business logic is from [Apollo graphql course. ](https://www.apollographql.com/tutorials/lift-off-part2/03-apollo-restdatasource) Full source code is also available in the accompanying repo for this course . 
+
+**Further explanation** : There is [an accompanying issue](https://github.com/webonyx/graphql-php/issues/1699) where I explained some of the boilerplate code . 
+
+## How to follow along ?
+1. Navigate to `examples/05-using-typeConfigDecorator-with-SDL` using the command line
+2. Run `composer install`
+3. Run `php -S localhost:8080 graphql.php`
+4. Use your favorite API client and make a request to `localhost:8080` . Provide the following as the request body : 
+
+```graphql
+  {
+    tracksForHome {
+      title
+      thumbnail
+      author {
+        id
+        name
+      }
+    }
+  }
+```
+
+5. You can also use `curl` : 
+```
+curl --data '{"query": "{ tracksForHome { title thumbnail author { id name } } }"}' --header "Content-Type: application/json" http://localhost:8080
+```
+

examples/05-using-typeConfigDecorator-with-SDL/app/models/Author.php

@@ -0,0 +1,11 @@
+<?php
+
+namespace App\Models;
+
+use Core\Model;
+
+class Author extends Model {
+  public static function find(int $id): array {
+    return static::get("author/$id");
+  }
+}

examples/05-using-typeConfigDecorator-with-SDL/app/models/Track.php

@@ -0,0 +1,11 @@
+<?php
+
+namespace App\Models;
+
+use Core\Model;
+
+class Track extends Model {
+  public static function all(): array {
+    return static::get('tracks');
+  }
+}

examples/05-using-typeConfigDecorator-with-SDL/composer.json

@@ -0,0 +1,11 @@
+{
+    "autoload": {
+        "psr-4": {
+            "App\\": "app/",
+            "Core\\": "core/"
+        }
+    },
+    "require": {
+        "webonyx/graphql-php": "^15.20"
+    }
+}

examples/05-using-typeConfigDecorator-with-SDL/core/Model.php

@@ -0,0 +1,18 @@
+<?php
+namespace Core;
+
+use Exception;
+
+class Model {
+  protected static $basePath = "https://odyssey-lift-off-rest-api.herokuapp.com/";
+  protected static function get(string $endpoint): array {
+    $url = static::$basePath . $endpoint;
+
+    $res =  file_get_contents($url);
+
+    if(!$res) {
+      throw new Exception("Failed to fetch data from url: $url");
+    }
+    return json_decode($res, true);
+  }
+}

examples/05-using-typeConfigDecorator-with-SDL/graphql.php

@@ -0,0 +1,50 @@
+<?php
+
+require __DIR__ . '/vendor/autoload.php';
+
+use App\Models\Track;
+use App\Models\Author;
+use GraphQL\GraphQL;
+use GraphQL\Utils\BuildSchema;
+
+ini_set('display_errors', 1);
+
+$typeConfigDecorator = function($typeConfig) {
+  /*
+    The hypothetical shape of $typeConfig in iterations :
+  
+    [
+    // Each iteration, the name property gets the name of a type from our schema like : Query, Track and Author
+    'name': "Query",
+    'fields': fn() => {}
+    ]
+  */
+  switch($typeConfig['name']) {
+    case "Query":
+      $typeConfig['fields'] = function() use ($typeConfig) {
+        $fields = $typeConfig['fields']();
+        $fields['tracksForHome']['resolve'] = fn() => Track::all();
+        return $fields;
+      };
+    break;
+    case "Track":
+      $typeConfig['fields'] = function() use ($typeConfig) {
+        $fields = $typeConfig['fields']();
+        $fields['author']['resolve'] = fn($track) => Author::find($track['authorId']);
+        return $fields;
+      };
+    break;
+  }
+  return $typeConfig;
+};
+$contents = file_get_contents(__DIR__ . '/schema.graphql');
+$schema = BuildSchema::build($contents, $typeConfigDecorator);
+
+$requestBody = file_get_contents('php://input');
+$parsedBody = json_decode($requestBody, true, 10);
+$queryString = $parsedBody['query'];
+
+$result = GraphQL::executeQuery($schema, $queryString);
+
+header('Content-Type: application/json');
+echo json_encode($result);

examples/05-using-typeConfigDecorator-with-SDL/schema.graphql

@@ -0,0 +1,19 @@
+type Query {
+  tracksForHome: [Track]
+
+}
+
+type Track {
+  id: ID!
+  title: String
+  thumbnail: String
+  length: Int
+  modulesCount: Int
+  author: Author
+}
+
+type Author {
+  id: ID!
+  name: String
+  photo: String
+}