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

Rytass Content Management System NestJS Base Module

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

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_param(paramIndex, decorator) {
    return function(target, key) {
        decorator(target, key, paramIndex);
    };
}
class ArticleSignatureDataLoader {
    articleVersionRepo;
    constructor(articleVersionRepo){
        this.articleVersionRepo = articleVersionRepo;
        this.versionSignaturesLoader = new DataLoader(async (ids)=>{
            const pairs = ids.map((token)=>{
                const [id, version] = token.split('|');
                const nVersion = Number(version);
                if (!id || Number.isNaN(nVersion) || nVersion < 0) {
                    throw new Error(`Invalid id: ${token}, please use format: id|version`);
                }
                return {
                    id,
                    version: Number(version)
                };
            });
            const qb = this.articleVersionRepo.createQueryBuilder('articleVersions');
            qb.leftJoinAndSelect('articleVersions.signatures', 'signatures');
            qb.leftJoinAndSelect('signatures.signatureLevel', 'signatureLevel');
            pairs.forEach((pair, index)=>{
                qb.orWhere(new Brackets((subQb)=>{
                    subQb.andWhere(`articleVersions.articleId = :id_${index}`, {
                        [`id_${index}`]: pair.id
                    });
                    subQb.andWhere(`articleVersions.version = :version_${index}`, {
                        [`version_${index}`]: pair.version
                    });
                    return subQb;
                }));
            });
            const versions = await qb.getMany();
            const versionMap = new Map(versions.map((version)=>[
                    `${version.articleId}|${version.version}`,
                    version
                ]));
            return ids.map((id)=>versionMap.get(id)?.signatures ?? []);
        }, {
            cacheMap: new LRUCache({
                max: 100,
                ttl: 1000 * 15,
                ttlAutopurge: true
            })
        });
    }
    versionSignaturesLoader;
}
ArticleSignatureDataLoader = _ts_decorate([
    Injectable(),
    _ts_param(0, Inject(RESOLVED_ARTICLE_VERSION_REPO))
], ArticleSignatureDataLoader);

export { ArticleSignatureDataLoader };