feat: allow user to choose between limit/offset and take/skip. (#508)

README.md

@@ -259,6 +259,14 @@ const paginateConfig: PaginateConfig<CatEntity> {
    * Description: Overrides the origin of absolute resource links if set.
    */
   origin: 'http://cats.example',
+
+  /**
+   * Required: false
+   * Type: string
+   * Description: Allow user to choose between limit/offset and take/skip.
+   * Default: PaginationType.TAKE_AND_SKIP
+   */
+  paginationType: PaginationType.LIMIT_AND_OFFSET,
 }
 ```
 
@@ -343,6 +351,29 @@ const config: PaginateConfig<CatEntity> = {
 const result = await paginate<CatEntity>(query, catRepo, config)
 ```
 
+## Usage of pagination type
+
+You can use either `limit`/`offset` or `take`/`skip` to return paginated results.
+
+### Example
+
+#### Code
+
+```typescript
+const config: PaginateConfig<CatEntity> = {
+  paginationType: PaginationType.LIMIT_AND_OFFSET,
+  // Or
+  paginationType: PaginationType.TAKE_AND_SKIP,
+}
+
+const result = await paginate<CatEntity>(query, catRepo, config)
+```
+
+> However, using `limit`/`offset` can return unexpected results.   
+> For more information
+> see [#477](https://github.com/ppetzold/nestjs-paginate/issues/477), [#4742](https://github.com/typeorm/typeorm/issues/4742)
+> and [#5670](https://github.com/typeorm/typeorm/issues/5670).
+
 ## Single Filters
 
 Filter operators must be whitelisted per column in `PaginateConfig`.

src/paginate.ts

@@ -52,6 +52,11 @@ export class Paginated<T> {
     }
 }
 
+export enum PaginationType {
+    LIMIT_AND_OFFSET = 'limit',
+    TAKE_AND_SKIP = 'take',
+}
+
 export interface PaginateConfig<T> {
     relations?: FindOptionsRelations<T> | RelationColumn<T>[]
     sortableColumns: Column<T>[]
@@ -69,11 +74,13 @@ export interface PaginateConfig<T> {
     withDeleted?: boolean
     relativePath?: boolean
     origin?: string
+    paginationType?: PaginationType
 }
 
 export const DEFAULT_MAX_LIMIT = 100
 export const DEFAULT_LIMIT = 20
 export const NO_PAGINATION = 0
+export const DEFAULT_PAGINATE_TYPE = PaginationType.TAKE_AND_SKIP
 
 export async function paginate<T extends ObjectLiteral>(
     query: PaginateQuery,
@@ -85,6 +92,7 @@ export async function paginate<T extends ObjectLiteral>(
     const defaultLimit = config.defaultLimit || DEFAULT_LIMIT
     const maxLimit = positiveNumberOrDefault(config.maxLimit, DEFAULT_MAX_LIMIT)
     const queryLimit = positiveNumberOrDefault(query.limit, defaultLimit)
+    const paginationType = config.paginationType || DEFAULT_PAGINATE_TYPE
 
     const isPaginated = !(queryLimit === NO_PAGINATION && maxLimit === NO_PAGINATION)
 
@@ -159,10 +167,14 @@ export async function paginate<T extends ObjectLiteral>(
     if (isPaginated) {
         // Switch from take and skip to limit and offset
         // due to this problem https://github.com/typeorm/typeorm/issues/5670
-        // (anyway this creates more clean query without double dinstict)
+        // (anyway this creates more clean query without double distinct)
         // queryBuilder.limit(limit).offset((page - 1) * limit)
+        if (paginationType === PaginationType.LIMIT_AND_OFFSET) {
+            queryBuilder.limit(limit).offset((page - 1) * limit)
+        } else {
             queryBuilder.take(limit).skip((page - 1) * limit)
         }
+    }
 
     if (config.relations) {
         // relations: ["relation"]