move types to helper file

src/helper.ts

@@ -0,0 +1,27 @@
+type Join<K, P> = K extends string ? (P extends string ? `${K}${'' extends P ? '' : '.'}${P}` : never) : never
+
+type Prev = [never, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, ...0[]]
+
+export type Column<T, D extends number = 2> = [D] extends [never]
+    ? never
+    : T extends Record<string, any>
+    ? {
+          [K in keyof T]-?: K extends string
+              ? T[K] extends Date
+                  ? `${K}`
+                  : T[K] extends Array<infer U>
+                  ? `${K}` | Join<K, Column<U, Prev[D]>>
+                  : `${K}` | Join<K, Column<T[K], Prev[D]>>
+              : never
+      }[keyof T]
+    : ''
+
+export type RelationColumn<T> = Extract<
+    Column<T>,
+    {
+        [K in Column<T>]: K extends `${infer R}.${string}` ? R : never
+    }[Column<T>]
+>
+
+export type Order<T> = [Column<T>, 'ASC' | 'DESC']
+export type SortBy<T> = Order<T>[]

src/paginate.ts

@@ -20,31 +20,7 @@ import { ServiceUnavailableException } from '@nestjs/common'
 import { values, mapKeys } from 'lodash'
 import { stringify } from 'querystring'
 import { WherePredicateOperator } from 'typeorm/query-builder/WhereClause'
-import { Join, Prev } from './utils'
+import { Column, Order, RelationColumn, SortBy } from './helper'
-
-type Column<T, D extends number = 2> = [D] extends [never]
-    ? never
-    : T extends Record<string, any>
-    ? {
-          [K in keyof T]-?: K extends string
-              ? T[K] extends Date
-                  ? `${K}`
-                  : T[K] extends Array<infer U>
-                  ? `${K}` | Join<K, Column<U, Prev[D]>>
-                  : `${K}` | Join<K, Column<T[K], Prev[D]>>
-              : never
-      }[keyof T]
-    : ''
-
-type RelationColumn<T> = Extract<
-    Column<T>,
-    {
-        [K in Column<T>]: K extends `${infer R}.${string}` ? R : never
-    }[Column<T>]
->
-
-type Order<T> = [Column<T>, 'ASC' | 'DESC']
-type SortBy<T> = Order<T>[]
 
 export class Paginated<T> {
     data: T[]

src/utils.ts

@@ -1,3 +0,0 @@
-export type Join<K, P> = K extends string ? (P extends string ? `${K}${'' extends P ? '' : '.'}${P}` : never) : never
-
-export type Prev = [never, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, ...0[]]