@rytass/cms-base-nestjs-module/data-loaders/category.dataloader.js

Rytass Content Management System NestJS Base Module

import { Injectable, Inject } from '@nestjs/common';
import DataLoader from 'dataloader';
import { RESOLVED_CATEGORY_REPO } from '../typings/cms-base-providers.js';
import { Repository } from 'typeorm';
import { LRUCache } from 'lru-cache';

function _ts_decorate(decorators, target, key, desc) {
    var c = arguments.length, r = c < 3 ? target : desc === null ? desc = Object.getOwnPropertyDescriptor(target, key) : desc, d;
    if (typeof Reflect === "object" && typeof Reflect.decorate === "function") r = Reflect.decorate(decorators, target, key, desc);
    else for(var i = decorators.length - 1; i >= 0; i--)if (d = decorators[i]) r = (c < 3 ? d(r) : c > 3 ? d(target, key, r) : d(target, key)) || r;
    return c > 3 && r && Object.defineProperty(target, key, r), r;
}
function _ts_metadata(k, v) {
    if (typeof Reflect === "object" && typeof Reflect.metadata === "function") return Reflect.metadata(k, v);
}
function _ts_param(paramIndex, decorator) {
    return function(target, key) {
        decorator(target, key, paramIndex);
    };
}
class CategoryDataLoader {
    categoryRepo;
    constructor(categoryRepo){
        this.categoryRepo = categoryRepo;
    }
    withParentsLoader = new DataLoader(async (ids)=>{
        const qb = this.categoryRepo.createQueryBuilder('categories');
        qb.innerJoinAndSelect('categories.multiLanguageNames', 'multiLanguageNames');
        qb.leftJoinAndSelect('categories.parents', 'parents');
        qb.leftJoinAndSelect('parents.multiLanguageNames', 'childMultiLanguageNames');
        qb.andWhere('categories.id IN (:...ids)', {
            ids
        });
        const categories = await qb.getMany();
        const categoryMap = new Map(categories.map((category)=>[
                category.id,
                category
            ]));
        return ids.map((id)=>categoryMap.get(id) ?? null);
    }, {
        cacheMap: new LRUCache({
            max: 100,
            ttl: 1000 * 15,
            ttlAutopurge: true
        })
    });
}
CategoryDataLoader = _ts_decorate([
    Injectable(),
    _ts_param(0, Inject(RESOLVED_CATEGORY_REPO)),
    _ts_metadata("design:type", Function),
    _ts_metadata("design:paramtypes", [
        typeof Repository === "undefined" ? Object : Repository
    ])
], CategoryDataLoader);

export { CategoryDataLoader };