@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, Repository } 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_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 ArticleSignatureDataLoader {
    articleVersionRepo;
    constructor(articleVersionRepo){
        this.articleVersionRepo = articleVersionRepo;
    }
    versionSignaturesLoader = new DataLoader(async (args)=>{
        const qb = this.articleVersionRepo.createQueryBuilder('articleVersions');
        qb.leftJoinAndSelect('articleVersions.signatures', 'signatures');
        qb.leftJoinAndSelect('signatures.signatureLevel', 'signatureLevel');
        args.forEach(({ id, version }, index)=>{
            qb.orWhere(new Brackets((subQb)=>{
                subQb.andWhere(`articleVersions.articleId = :id_${index}`, {
                    [`id_${index}`]: id
                });
                subQb.andWhere(`articleVersions.version = :version_${index}`, {
                    [`version_${index}`]: version
                });
                return subQb;
            }));
        });
        qb.addOrderBy('signatures.signedAt', 'DESC');
        const versions = await qb.getMany();
        const versionMap = new Map(versions.map((version)=>[
                `${version.articleId}|${version.version}`,
                version
            ]));
        return args.map(({ id, version })=>versionMap.get(`${id}|${version}`)?.signatures ?? []);
    }, {
        cache: true,
        cacheMap: new LRUCache({
            max: 100,
            ttl: 1000 * 15,
            ttlAutopurge: true
        }),
        cacheKeyFn: (args)=>`${args.id}|${args.version}`
    });
}
ArticleSignatureDataLoader = _ts_decorate([
    Injectable(),
    _ts_param(0, Inject(RESOLVED_ARTICLE_VERSION_REPO)),
    _ts_metadata("design:type", Function),
    _ts_metadata("design:paramtypes", [
        typeof Repository === "undefined" ? Object : Repository
    ])
], ArticleSignatureDataLoader);

export { ArticleSignatureDataLoader };