Merge branch 'v2-beta-dataloader' into v2-beta

nuwave · Mar 20, 2018 · eef99ab · eef99ab
2 parents ee3957f + dcc1936
commit eef99ab
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Showing 6 changed files with 192 additions and 23 deletions.
diff --git a/src/GraphQL.php b/src/GraphQL.php
@@ -65,6 +65,16 @@ public function execute($query, $context = null, $variables = [], $rootValue = n
         $result = $this->queryAndReturnResult($query, $context, $variables, $rootValue);
 
         if (! empty($result->errors)) {
+            foreach ($result->errors as $error) {
+                if ($error instanceof \Exception) {
+                    info('GraphQL Error:', [
+                        'code' => $error->getCode(),
+                        'message' => $error->getMessage(),
+                        'trace' => $error->getTraceAsString(),
+                    ]);
+                }
+            }
+
             return [
                 'data' => $result->data,
                 'errors' => array_map([$this, 'formatError'], $result->errors),
@@ -112,6 +122,26 @@ public function buildSchema()
         return $this->schema()->build($schema);
     }
 
+    /**
+     * Batch field resolver.
+     *
+     * @param string $abstract
+     * @param mixed  $key
+     * @param array  $data
+     * @param string $name
+     *
+     * @return \GraphQL\Deferred
+     */
+    public function batch($abstract, $key, array $data = [], $name = null)
+    {
+        $name = $name ?: $abstract;
+        $instance = app()->has($name)
+            ? resolve($name)
+            : app()->instance($name, resolve($abstract));
+
+        return $instance->load($key, $data);
+    }
+
     /**
      * Get an instance of the schema builder.
      *

diff --git a/src/Schema/Directives/Fields/BelongsTo.php b/src/Schema/Directives/Fields/BelongsTo.php
@@ -4,6 +4,7 @@
 
 use Nuwave\Lighthouse\Schema\Values\FieldValue;
 use Nuwave\Lighthouse\Support\Contracts\FieldResolver;
+use Nuwave\Lighthouse\Support\DataLoader\Loaders\BelongsToLoader;
 use Nuwave\Lighthouse\Support\Traits\HandlesDirectives;
 
 class BelongsTo implements FieldResolver
@@ -36,7 +37,11 @@ public function handle(FieldValue $value)
         );
 
         return $value->setResolver(function ($root, array $args) use ($relation) {
-            return $root->{$relation};
+            return graphql()->batch(BelongsToLoader::class, $root->getKey(), [
+                'relation' => $relation,
+                'root' => $root,
+                'args' => $args,
+            ]);
         });
     }
 }
diff --git a/src/Schema/Directives/Fields/HasManyDirective.php b/src/Schema/Directives/Fields/HasManyDirective.php
@@ -8,6 +8,7 @@
 use Nuwave\Lighthouse\Schema\Types\PaginatorField;
 use Nuwave\Lighthouse\Schema\Values\FieldValue;
 use Nuwave\Lighthouse\Support\Contracts\FieldResolver;
+use Nuwave\Lighthouse\Support\DataLoader\Loaders\HasManyLoader;
 use Nuwave\Lighthouse\Support\Exceptions\DirectiveException;
 use Nuwave\Lighthouse\Support\Traits\CanParseTypes;
 use Nuwave\Lighthouse\Support\Traits\HandlesDirectives;
@@ -141,13 +142,10 @@ protected function connectionTypeResolver($relation, FieldValue $value)
             });
 
         return function ($parent, array $args, $context = null, ResolveInfo $info = null) use ($relation, $scopes) {
-            $builder = call_user_func([$parent, $relation]);
-
-            return $builder->when(! empty($scopes), function ($q) use ($scopes, $args) {
-                foreach ($scopes as $scope) {
-                    call_user_func_array([$q, $scope], [$args]);
-                }
-            })->relayConnection($args);
+            return graphql()->batch(HasManyLoader::class, $parent->getKey(), array_merge(
+                compact('relation', 'parent', 'args', 'scopes'),
+                ['type' => 'relay']
+            ), camel_case($parent->getTable().'_'.$relation));
         };
     }
 
@@ -195,13 +193,10 @@ protected function paginatorTypeResolver($relation, FieldValue $value)
             });
 
         return function ($parent, array $args, $context = null, ResolveInfo $info = null) use ($relation, $scopes) {
-            $builder = call_user_func([$parent, $relation]);
-
-            return $builder->when(! empty($scopes), function ($q) use ($scopes, $args) {
-                foreach ($scopes as $scope) {
-                    call_user_func_array([$q, $scope], [$args]);
-                }
-            })->paginatorConnection($args);
+            return graphql()->batch(HasManyLoader::class, $parent->getKey(), array_merge(
+                compact('relation', 'parent', 'args', 'scopes'),
+                ['type' => 'paginator']
+            ), camel_case($parent->getTable().'_'.$relation));
         };
     }
 
@@ -218,14 +213,10 @@ protected function defaultResolver($relation, FieldValue $value)
         $scopes = $this->getScopes($value);
 
         return function ($parent, array $args) use ($relation, $scopes) {
-            // TODO: Wrap w/ data loader to prevent N+1
-            $builder = call_user_func([$parent, $relation]);
-            // TODO: Create scopeGqlQuery scope to allow adjustments for $args.
-            return $builder->when(! empty($scopes), function ($q) use ($scopes, $args) {
-                foreach ($scopes as $scope) {
-                    call_user_func_array([$q, $scope], [$args]);
-                }
-            })->get();
+            return graphql()->batch(HasManyLoader::class, $parent->getKey(), array_merge(
+                compact('relation', 'parent', 'args', 'scopes'),
+                ['type' => 'default']
+            ), camel_case($parent->getTable().'_'.$relation));
         };
     }
 

diff --git a/src/Support/DataLoader/BatchLoader.php b/src/Support/DataLoader/BatchLoader.php
@@ -0,0 +1,62 @@
+<?php
+
+namespace Nuwave\Lighthouse\Support\DataLoader;
+
+use GraphQL\Deferred;
+
+abstract class BatchLoader
+{
+    /**
+     * Keys to resolve.
+     *
+     * @var \Illuminate\Support\Collection
+     */
+    protected $keys = [];
+
+    /**
+     * Check if data has been loaded.
+     *
+     * @var bool
+     */
+    protected $hasLoaded = false;
+
+    /**
+     * Load object by key.
+     *
+     * @param mixed $key
+     * @param array $data
+     *
+     * @return Deferred
+     */
+    public function load($key, array $data = [])
+    {
+        $this->keys[$key] = $data;
+
+        return new Deferred(function () use ($key) {
+            if (! $this->hasLoaded) {
+                $this->resolve();
+                $this->hasLoaded = true;
+            }
+
+            return array_get($this->keys, "$key.value");
+        });
+    }
+
+    /**
+     * Set key value.
+     *
+     * @param mixed $key
+     * @param mixed $value
+     */
+    protected function set($key, $value)
+    {
+        if ($field = array_get($this->keys, $key)) {
+            $this->keys[$key] = array_merge($field, compact('value'));
+        }
+    }
+
+    /**
+     * Resolve keys.
+     */
+    abstract public function resolve();
+}
diff --git a/src/Support/DataLoader/Loaders/BelongsToLoader.php b/src/Support/DataLoader/Loaders/BelongsToLoader.php
@@ -0,0 +1,26 @@
+<?php
+
+namespace Nuwave\Lighthouse\Support\DataLoader\Loaders;
+
+use Nuwave\Lighthouse\Support\DataLoader\BatchLoader;
+
+class BelongsToLoader extends BatchLoader
+{
+    /**
+     * Resolve keys.
+     */
+    public function resolve()
+    {
+        collect($this->keys)->map(function ($item) {
+            return array_merge($item, ['json' => json_encode($item['args'])]);
+        })->groupBy('json')->each(function ($items) {
+            $relation = array_get($items->first(), 'relation');
+            $models = $items->pluck('root');
+
+            $models->fetch([$relation]);
+            $models->each(function ($model) use ($relation) {
+                $this->set($model->id, $model->getRelation($relation));
+            });
+        });
+    }
+}
diff --git a/src/Support/DataLoader/Loaders/HasManyLoader.php b/src/Support/DataLoader/Loaders/HasManyLoader.php
@@ -0,0 +1,55 @@
+<?php
+
+namespace Nuwave\Lighthouse\Support\DataLoader\Loaders;
+
+use Nuwave\Lighthouse\Support\DataLoader\BatchLoader;
+use Nuwave\Lighthouse\Support\Traits\HandlesGlobalId;
+
+class HasManyLoader extends BatchLoader
+{
+    use HandlesGlobalId;
+
+    /**
+     * Resolve keys.
+     */
+    public function resolve()
+    {
+        collect($this->keys)->map(function ($item) {
+            return array_merge($item, ['json' => json_encode($item['args'])]);
+        })->groupBy('json')->each(function ($items) {
+            $first = $items->first();
+            $parents = $items->pluck('parent');
+            $scopes = array_get($first, 'scopes', []);
+            $relation = $first['relation'];
+            $type = $first['type'];
+            $args = $first['args'];
+
+            $constraints = [$relation => function ($q) use ($scopes, $args) {
+                foreach ($scopes as $scope) {
+                    call_user_func_array([$q, $scope], [$args]);
+                }
+            }];
+
+            switch ($type) {
+                case 'relay':
+                    $first = data_get($args, 'first', 15);
+                    $after = $this->decodeCursor($args);
+                    $currentPage = $first && $after ? floor(($first + $after) / $first) : 1;
+                    $parents->fetchForPage($first, $currentPage, $constraints);
+                    break;
+                case 'paginator':
+                    $first = data_get($args, 'count', 15);
+                    $page = data_get($args, 'page', 1);
+                    $parents->fetchForPage($first, $page, $constraints);
+                    break;
+                default:
+                    $parents->fetch($constraints);
+                    break;
+            }
+
+            $parents->each(function ($model) use ($relation) {
+                $this->set($model->id, $model->getRelation($relation));
+            });
+        });
+    }
+}