Keep the query and pagination capabilities of relation directives when disabling batch loading

CHANGELOG.md

@@ -11,6 +11,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - Enable multiple queries in a single request by clearing `BatchLoader` instances
   after executing each query https://github.com/nuwave/lighthouse/pull/1030
+- Keep the query and pagination capabilities of relation directives when disabling batch loading https://github.com/nuwave/lighthouse/pull/1083
 
 ## [4.7.1](https://github.com/nuwave/lighthouse/compare/v4.7.0...v4.7.1)
 

src/Execution/Arguments/ArgumentSet.php

@@ -110,11 +110,11 @@ public function rename(): self
     /**
      * Apply ArgBuilderDirectives and scopes to the builder.
      *
-     * @param  \Illuminate\Database\Query\Builder|\Illuminate\Database\Eloquent\Builder  $builder
+     * @param  \Illuminate\Database\Query\Builder|\Illuminate\Database\Eloquent\Builder|\Illuminate\Database\Eloquent\Model|\Illuminate\Database\Eloquent\Relations\Relation  $builder
      * @param  string[]  $scopes
      * @param  \Closure  $directiveFilter
      *
-     * @return \Illuminate\Database\Query\Builder|\Illuminate\Database\Eloquent\Builder
+     * @return \Illuminate\Database\Query\Builder|\Illuminate\Database\Eloquent\Builder|\Illuminate\Database\Eloquent\Model|\Illuminate\Database\Eloquent\Relations\Relation
      */
     public function enhanceBuilder($builder, array $scopes, Closure $directiveFilter = null)
     {

src/Execution/DataLoader/BatchLoader.php

@@ -4,12 +4,9 @@
 
 use GraphQL\Deferred;
 use Illuminate\Support\Collection;
-use Nuwave\Lighthouse\Support\Traits\HandlesCompositeKey;
 
 abstract class BatchLoader
 {
-    use HandlesCompositeKey;
-
     /**
      * Active BatchLoader instances.
      *
@@ -140,4 +137,19 @@ function ($key) use ($metaInfo): Deferred {
      * @return array<mixed, mixed>
      */
     abstract public function resolve(): array;
+
+    /**
+     * Build a key out of one or more given keys, supporting composite keys.
+     *
+     * E.g.: $primaryKey = ['key1', 'key2'];.
+     *
+     * @param  mixed  $key
+     * @return string
+     */
+    protected function buildKey($key): string
+    {
+        return is_array($key)
+            ? implode('___', $key)
+            : $key;
+    }
 }

src/Execution/DataLoader/ModelRelationFetcher.php

@@ -10,14 +10,12 @@
 use Illuminate\Pagination\LengthAwarePaginator;
 use Illuminate\Support\Collection;
 use Illuminate\Support\Str;
-use Nuwave\Lighthouse\Support\Traits\HandlesCompositeKey;
+use Nuwave\Lighthouse\Pagination\PaginationArgs;
 use ReflectionClass;
 use ReflectionMethod;
 
 class ModelRelationFetcher
 {
-    use HandlesCompositeKey;
-
     /**
      * The parent models that relations should be loaded for.
      *
@@ -33,109 +31,72 @@ class ModelRelationFetcher
     protected $relations;
 
     /**
-     * @param  mixed  $models The parent models that relations should be loaded for
+     * @param  \Illuminate\Database\Eloquent\Collection  $models  The parent models that relations should be loaded for
      * @param  mixed[]  $relations The relations to be loaded. Same format as the `with` method in Eloquent builder.
      * @return void
      */
-    public function __construct($models, array $relations)
-    {
-        $this->setModels($models);
-        $this->setRelations($relations);
-    }
-
-    /**
-     * Set the relations to be loaded.
-     *
-     * @param  array  $relations
-     * @return $this
-     */
-    public function setRelations(array $relations): self
+    public function __construct(EloquentCollection $models, array $relations)
     {
+        $this->models = $models;
         // Parse and set the relations.
         $this->relations = $this->newModelQuery()
             ->with($relations)
             ->getEagerLoads();
-
-        return $this;
     }
 
     /**
-     * Return a fresh instance of a query builder for the underlying model.
+     * Load all relations for the model, but constrain the query to the current page.
      *
-     * @return \Illuminate\Database\Eloquent\Builder
+     * @param  \Nuwave\Lighthouse\Pagination\PaginationArgs  $paginationArgs
+     * @return \Illuminate\Database\Eloquent\Collection
      */
-    protected function newModelQuery(): EloquentBuilder
+    public function loadRelationsForPage(PaginationArgs $paginationArgs): EloquentCollection
     {
-        return $this->models()
-            ->first()
-            ->newModelQuery();
-    }
+        foreach ($this->relations as $name => $constraints) {
+            $this->loadRelationForPage($paginationArgs, $name, $constraints);
+        }
 
-    /**
-     * Get all the underlying models.
-     *
-     * @return \Illuminate\Database\Eloquent\Collection<\Illuminate\Database\Eloquent\Model>
-     */
-    public function models(): EloquentCollection
-    {
         return $this->models;
     }
 
     /**
-     * Set one or more Model instances as an EloquentCollection.
-     *
-     * @param  mixed  $models
-     * @return $this
-     */
-    protected function setModels($models): self
-    {
-        $this->models = $models instanceof EloquentCollection
-            ? $models
-            : new EloquentCollection($models);
-
-        return $this;
-    }
-
-    /**
-     * Load all the relations of all the models.
+     * Reload the models to get the `{relation}_count` attributes of models set.
      *
-     * @return $this
+     * @return \Illuminate\Database\Eloquent\Collection
      */
-    public function loadRelations(): self
+    public function reloadModelsWithRelationCount(): EloquentCollection
     {
-        $this->models->load($this->relations);
-
-        return $this;
-    }
+        $ids = $this->models->modelKeys();
 
-    /**
-     * Load all relations for the model, but constrain the query to the current page.
-     *
-     * @param  int  $perPage
-     * @param  int  $page
-     * @return $this
-     */
-    public function loadRelationsForPage(int $perPage, int $page = 1): self
-    {
-        foreach ($this->relations as $name => $constraints) {
-            $this->loadRelationForPage($perPage, $page, $name, $constraints);
-        }
+        $this->models = $this
+            ->newModelQuery()
+            ->withCount($this->relations)
+            ->whereKey($ids)
+            ->get()
+            ->filter(function (Model $model) use ($ids): bool {
+                // We might have gotten some models that we did not have before
+                // so we filter them out
+                return in_array(
+                    $model->getKey(),
+                    $ids,
+                    true
+                );
+            });
 
-        return $this;
+        return $this->models;
     }
 
     /**
      * Load only one page of relations of all the models.
      *
      * The relation will be converted to a `Paginator` instance.
      *
-     * @param  int  $first
-     * @param  int  $page
+     * @param  \Nuwave\Lighthouse\Pagination\PaginationArgs  $paginationArgs
      * @param  string  $relationName
      * @param  \Closure  $relationConstraints
-     * @return $this
+     * @return void
      */
-    public function loadRelationForPage(int $first, int $page, string $relationName, Closure $relationConstraints): self
+    protected function loadRelationForPage(PaginationArgs $paginationArgs, string $relationName, Closure $relationConstraints): void
     {
         // Load the count of relations of models, this will be the `total` argument of `Paginator`.
         // Be aware that this will reload all the models entirely with the count of their relations,
@@ -145,8 +106,8 @@ public function loadRelationForPage(int $first, int $page, string $relationName,
         $relations = $this
             ->buildRelationsFromModels($relationName, $relationConstraints)
             ->map(
-                function (Relation $relation) use ($first, $page) {
-                    return $relation->forPage($page, $first);
+                function (Relation $relation) use ($paginationArgs) {
+                    return $relation->forPage($paginationArgs->page, $paginationArgs->first);
                 }
             );
 
@@ -161,52 +122,19 @@ function (Relation $relation) use ($first, $page) {
 
         $this->associateRelationModels($relationName, $relationModels);
 
-        $this->convertRelationToPaginator($first, $page, $relationName);
-
-        return $this;
-    }
-
-    /**
-     * Reload the models to get the `{relation}_count` attributes of models set.
-     *
-     * @return $this
-     */
-    public function reloadModelsWithRelationCount(): self
-    {
-        /** @var \Illuminate\Database\Eloquent\Builder $query */
-        $query = $this->models()
-            ->first()
-            ->newQuery()
-            ->withCount($this->relations);
-
-        $ids = $this->getModelIds();
-
-        $reloadedModels = $query
-            ->whereKey($ids)
-            ->get()
-            ->filter(function (Model $model) use ($ids): bool {
-                return in_array(
-                    $model->getKey(),
-                    $ids,
-                    true
-                );
-            });
-
-        return $this->setModels($reloadedModels);
+        $this->convertRelationToPaginator($paginationArgs, $relationName);
     }
 
     /**
-     * Extract the primary keys from the underlying models.
+     * Return a fresh instance of a query builder for the underlying model.
      *
-     * @return mixed[]
+     * @return \Illuminate\Database\Eloquent\Builder
      */
-    protected function getModelIds(): array
+    protected function newModelQuery(): EloquentBuilder
     {
         return $this->models
-            ->map(function (Model $model) {
-                return $model->getKey();
-            })
-            ->all();
+            ->first()
+            ->newModelQuery();
     }
 
     /**
@@ -284,27 +212,11 @@ protected function loadDefaultWith(EloquentCollection $collection): self
      * @param  string  $relationName
      * @return string
      */
-    public function getRelationCountName(string $relationName): string
+    protected function getRelationCountName(string $relationName): string
     {
         return Str::snake("{$relationName}_count");
     }
 
-    /**
-     * Get an associative array of relations, keyed by the models primary key.
-     *
-     * @param  string  $relationName
-     * @return mixed[]
-     */
-    public function getRelationDictionary(string $relationName): array
-    {
-        return $this->models
-            ->mapWithKeys(
-                function (Model $model) use ($relationName): array {
-                    return [$this->buildKey($model->getKey()) => $model->getRelation($relationName)];
-                }
-            )->all();
-    }
-
     /**
      * Merge all the relation queries into a single query with UNION ALL.
      *
@@ -326,14 +238,13 @@ function (EloquentBuilder $builder, Relation $relation) {
     }
 
     /**
-     * @param  int  $first
-     * @param  int  $page
+     * @param  \Nuwave\Lighthouse\Pagination\PaginationArgs  $paginationArgs
      * @param  string  $relationName
      * @return $this
      */
-    protected function convertRelationToPaginator(int $first, int $page, string $relationName): self
+    protected function convertRelationToPaginator(PaginationArgs $paginationArgs, string $relationName): self
     {
-        $this->models->each(function (Model $model) use ($page, $first, $relationName): void {
+        $this->models->each(function (Model $model) use ($paginationArgs, $relationName): void {
             $total = $model->getAttribute(
                 $this->getRelationCountName($relationName)
             );
@@ -343,8 +254,8 @@ protected function convertRelationToPaginator(int $first, int $page, string $rel
                 [
                     'items' => $model->getRelation($relationName),
                     'total' => $total,
-                    'perPage' => $first,
-                    'currentPage' => $page,
+                    'perPage' => $paginationArgs->first,
+                    'currentPage' => $paginationArgs->page,
                     'options' => [],
                 ]
             );