better typing for relation

src/crud-base.ts

@@ -23,14 +23,15 @@ import { ConsoleLogger } from '@nestjs/common';
 import { camelCase } from 'typeorm/util/StringUtils';
 import _ from 'lodash';
 import { ClassType } from './utility/insert-field';
+import { RecursiveKeyOf } from './utility/recursive-key-of';
 
 export type EntityId<T extends { id: any }> = T['id'];
-export interface RelationDef {
-  name: string;
+export interface RelationDef<T> {
+  name: T;
   inner?: boolean;
 }
 
-export const Inner = (name: string): RelationDef => {
+export const Inner = <T>(name: T): RelationDef<T> => {
   return { name, inner: true };
 };
 
@@ -39,7 +40,7 @@ export type ValidCrudEntity<T> = Record<string, any> & {
 } & Partial<QueryWise<T> & DeletionWise & EntityHooks & PageSettingsFactory>;
 
 export interface CrudOptions<T extends ValidCrudEntity<T>> {
-  relations?: (string | RelationDef)[];
+  relations?: (RecursiveKeyOf<T> | RelationDef<RecursiveKeyOf<T>>)[];
   extraGetQuery?: (qb: SelectQueryBuilder<T>) => void;
   hardDelete?: boolean;
 }
@@ -52,7 +53,10 @@ export class CrudBase<T extends ValidCrudEntity<T>> {
   readonly entityPaginatedReturnMessageDto = PaginatedReturnMessageDto(
     this.entityClass,
   );
-  readonly entityRelations: (string | RelationDef)[];
+  readonly entityRelations: (
+    | RecursiveKeyOf<T>
+    | RelationDef<RecursiveKeyOf<T>>
+  )[];
   readonly extraGetQuery: (qb: SelectQueryBuilder<T>) => void;
   readonly log = new ConsoleLogger(`${this.entityClass.name}Service`);
 
@@ -191,7 +195,10 @@ export class CrudBase<T extends ValidCrudEntity<T>> {
     return camelCase(this.entityName);
   }
 
-  _applyRelationToQuery(qb: SelectQueryBuilder<T>, relation: RelationDef) {
+  _applyRelationToQuery(
+    qb: SelectQueryBuilder<T>,
+    relation: RelationDef<RecursiveKeyOf<T>>,
+  ) {
     const { name } = relation;
     const relationUnit = name.split('.');
     const base =
@@ -209,7 +216,7 @@ export class CrudBase<T extends ValidCrudEntity<T>> {
   _applyRelationsToQuery(qb: SelectQueryBuilder<T>) {
     for (const relation of this.entityRelations) {
       if (typeof relation === 'string') {
-        this._applyRelationToQuery(qb, { name: relation });
+        this._applyRelationToQuery(qb, { name: relation as any });
       } else {
         this._applyRelationToQuery(qb, relation);
       }

src/utility/recursive-key-of.ts

+/* eslint-disable @typescript-eslint/ban-types */
+
+export type RecursiveKeyOf<TObj extends Record<string, any>> = {
+  [TKey in keyof TObj & string]: RecursiveKeyOfHandleValue<
+    TObj[TKey],
+    `${TKey}`
+  >;
+}[keyof TObj & string];
+
+type RecursiveKeyOfInner<TObj extends Record<string, any>> = {
+  [TKey in keyof TObj & string]: RecursiveKeyOfHandleValue<
+    TObj[TKey],
+    `.${TKey}`
+  >;
+}[keyof TObj & string];
+
+type RecursiveKeyOfHandleValue<TValue, Text extends string> = TValue extends
+  | Function
+  | ((...args: any[]) => any)
+  | (new (...args: any[]) => any)
+  ? never
+  : TValue extends Date | string | number | boolean
+  ? never // Text
+  : TValue extends (infer TItem)[]
+  ? Text | `${Text}${RecursiveKeyOfInner<TItem>}`
+  : TValue extends Record<string, any>
+  ? Text | `${Text}${RecursiveKeyOfInner<TValue>}`
+  : never; // Text;

tests/module.spec.ts

 import { NestExpressApplication } from '@nestjs/platform-express';
 import { Controller, Injectable } from '@nestjs/common';
 import { CrudService } from '../src/crud-base';
-import { Gender, User } from './utility/user';
+import { User } from './utility/user';
 import { RestfulFactory } from '../src/decorators';
-import { Test } from '@nestjs/testing';
-import { InjectDataSource, TypeOrmModule } from '@nestjs/typeorm';
+import { InjectDataSource } from '@nestjs/typeorm';
 import { DataSource } from 'typeorm';
-import request from 'supertest';
 
 @Injectable()
 class UserService extends CrudService(User) {

tests/utility/user.ts

 import { Entity, Index } from 'typeorm';
-import { DateColumn, EnumColumn, IntColumn, NotChangeable, NotColumn, NotWritable, StringColumn } from '../../src/decorators';
+import {
+  DateColumn,
+  EnumColumn,
+  IntColumn,
+  NotChangeable,
+  NotColumn,
+  NotWritable,
+  StringColumn,
+} from '../../src/decorators';
 import { IdBase, StringIdBase } from '../../src/bases';
 
 export enum Gender {
@@ -7,6 +15,11 @@ export enum Gender {
   M = 'M',
 }
 
+export class Book {
+  id: number;
+  name: string;
+}
+
 @Entity()
 export class User extends IdBase() {
   @Index()
@@ -28,6 +41,8 @@ export class User extends IdBase() {
 
   @NotColumn()
   birthday: Date;
+
+  books: Book[];
 }
 
 @Entity()