From 90e97354fcf20784ddcb04d51a6577f8ed2bdf86 Mon Sep 17 00:00:00 2001
From: Zao Soula <contact@zaosoula.fr>
Date: Sat, 14 Dec 2024 19:58:24 +0100
Subject: [PATCH] feat(preloader): add preloadOnce to preload a relationship
 only once

---
 src/orm/preloader/index.ts | 12 ++++++++++++
 src/types/model.ts         |  2 ++
 src/types/relations.ts     |  3 +++
 3 files changed, 17 insertions(+)

diff --git a/src/orm/preloader/index.ts b/src/orm/preloader/index.ts
index 2850bd0c..d942c823 100644
--- a/src/orm/preloader/index.ts
+++ b/src/orm/preloader/index.ts
@@ -128,6 +128,18 @@ export class Preloader implements PreloaderContract<LucidRow> {
     return this.load(name, callback)
   }
 
+  /**
+   * Define a relationship to preload, but only if they are not
+   * already preloaded
+   */
+  preloadOnce(name: any): this {
+    if (!this.preloads[name]) {
+      return this.load(name)
+    }
+
+    return this
+  }
+
   /**
    * Toggle query debugging
    */
diff --git a/src/types/model.ts b/src/types/model.ts
index 0b41283f..7052c993 100644
--- a/src/types/model.ts
+++ b/src/types/model.ts
@@ -42,6 +42,7 @@ import {
   WithAggregate,
   WithCount,
   PreloadWithoutCallback,
+  PreloadOnce,
 } from './relations.js'
 
 /**
@@ -481,6 +482,7 @@ export interface ModelQueryBuilderContract<Model extends LucidModel, Result = In
    * Define relationships to be preloaded
    */
   preload: Preload<InstanceType<Model>, this>
+  preloadOnce: PreloadOnce<InstanceType<Model>, this>
 
   /**
    * Aggregates
diff --git a/src/types/relations.ts b/src/types/relations.ts
index 3291aff3..c96b9291 100644
--- a/src/types/relations.ts
+++ b/src/types/relations.ts
@@ -1065,6 +1065,9 @@ export interface PreloadWithoutCallback<Model extends LucidRow, Builder> {
   <Name extends ExtractModelRelations<Model>>(relation: Name): Builder
 }
 
+export interface PreloadOnce<Model extends LucidRow, Builder>
+  extends PreloadWithoutCallback<Model, Builder> {}
+
 /**
  * Shape of the preloader to preload relationships
  */