mongoose-crud.service.ts

import { ModelType } from "@hasezoey/typegoose/lib/types";
import { CrudRequest, CreateManyDto, GetManyDefaultResponse, CrudService } from "@nestjsx/crud";
import { BadRequestException, NotFoundException } from "@nestjs/common";
import { mongoose } from "@hasezoey/typegoose";

export class MongooseCrudService<T> extends CrudService<T> {
  constructor(public model: ModelType<T>) {
    super()
  }

  buildQuery(req: CrudRequest) {
    let { limit = 10, page = 1, offset: skip = 0, filter = [], fields = [], sort = [], join = [], paramsFilter = [] } = req.parsed
    if (page > 1) {
      skip = (page - 1) * limit
    }
    const options = {
      page,
      skip,
      limit,
      sort: sort.reduce((acc, v) => (acc[v.field] = v.order === 'ASC' ? 1 : -1, acc), {}),
      populate: join.map(v => v.field),
      select: fields.join(' ')
    }
    const where = filter.reduce((acc, { field, operator, value }) => {
      let cond = null
      switch (operator) {
        case 'starts':
          cond = new RegExp(`^${value}`, 'i')
          break;
        case 'ends':
          cond = new RegExp(`${value}\$`, 'i')
          break;

        case 'cont':
          cond = new RegExp(`${value}`, 'i')
          break;
        case 'excl':
          cond = { $ne: new RegExp(`${value}`, 'i') }
          break;
        case 'notin':
          cond = { $nin: value }
          break
        case 'isnull':
          cond = null
          break
        case 'notnull':
          cond = { $ne: null }
          break
        case 'between':
          const [min, max] = value
          cond = { $gte: min, $lte: max }
          break
        default:
          cond = { [`\$${operator}`]: value }
      }
      acc[field] = cond
      return acc
    }, {})
    const idParam = paramsFilter.find(v => v.field === 'id')
    return { options, where, id: idParam ? idParam.value : null }
  }

  async getMany(req: CrudRequest) {

    const { options, where } = this.buildQuery(req)
    const queryBuilder = this.model.find().setOptions({
      ...options
    }).where({
      ...where
    })
    options.populate.map(v => {
      queryBuilder.populate(v)
    })

    const data = await queryBuilder.exec()
    if (options.page) {
      const total = await this.model.countDocuments(where)
      return this.createPageInfo(data, total, options.limit, options.skip)
    }
    return data
  }
  async getOne(req: CrudRequest): Promise<T> {
    const { options, where, id } = this.buildQuery(req)
    const queryBuilder = this.model.findById(id).setOptions({
      ...options
    }).where({
      ...where
    })
    options.populate.map(v => {
      queryBuilder.populate(v)
    })

    const data = await queryBuilder.exec()
    return data
  }
  createOne(req: CrudRequest, dto: T): Promise<T> {
    throw new Error("Method not implemented.");
  }
  createMany(req: CrudRequest, dto: CreateManyDto<any>): Promise<T[]> {
    throw new Error("Method not implemented.");
  }
  updateOne(req: CrudRequest, dto: T): Promise<T> {
    throw new Error("Method not implemented.");
  }
  replaceOne(req: CrudRequest, dto: T): Promise<T> {
    throw new Error("Method not implemented.");
  }
  deleteOne(req: CrudRequest): Promise<void | T> {
    throw new Error("Method not implemented.");
  }
  throwBadRequestException(msg?: any): BadRequestException {
    throw new Error("Method not implemented.");
  }
  throwNotFoundException(name: string): NotFoundException {
    throw new Error("Method not implemented.");
  }
}