| 1 | /* |
| 2 | * @Author: nevin |
| 3 | * @Date: 2025-01-20 16:36:41 |
| 4 | * @LastEditTime: 2025-02-22 17:43:47 |
| 5 | * @LastEditors: nevin |
| 6 | * @Description: |
| 7 | */ |
| 8 | import { Model } from 'mongoose'; |
| 9 | import { |
| 10 | IPaginationMeta, |
| 11 | IPaginationOptions, |
| 12 | PaginationTypeEnum, |
| 13 | } from './interface'; |
| 14 | import { Pagination } from './pagination'; |
| 15 | |
| 16 | const DEFAULT_LIMIT = 20; |
| 17 | const DEFAULT_PAGE = 1; |
| 18 | |
| 19 | export function resolveOptions( |
| 20 | options: IPaginationOptions, |
| 21 | ): [number, number, PaginationTypeEnum] { |
| 22 | const { page, pageSize, paginationType } = options; |
| 23 | |
| 24 | return [ |
| 25 | page || DEFAULT_PAGE, |
| 26 | pageSize || DEFAULT_LIMIT, |
| 27 | paginationType || PaginationTypeEnum.TAKE_AND_SKIP, |
| 28 | ]; |
| 29 | } |
| 30 | |
| 31 | export function createPaginationObject<T>({ |
| 32 | items, |
| 33 | totalItems, |
| 34 | currentPage, |
| 35 | limit, |
| 36 | }: { |
| 37 | items: T[]; |
| 38 | totalItems?: number; |
| 39 | currentPage: number; |
| 40 | limit: number; |
| 41 | }): Pagination<T> { |
| 42 | const totalPages = |
| 43 | totalItems !== undefined ? Math.ceil(totalItems / limit) : undefined; |
| 44 | |
| 45 | const meta: IPaginationMeta = { |
| 46 | totalItems, |
| 47 | itemCount: items.length, |
| 48 | itemsPerPage: +limit, |
| 49 | totalPages, |
| 50 | currentPage: +currentPage, |
| 51 | }; |
| 52 | |
| 53 | return new Pagination<T>(items, meta); |
| 54 | } |
| 55 | |
| 56 | export async function paginateModel<T>( |
| 57 | model: Model<T>, |
| 58 | options: IPaginationOptions, |
| 59 | condition: any, |
| 60 | populate?: any, |
| 61 | sort?: any, |
| 62 | ): Promise<Pagination<T>> { |
| 63 | const [page, limit] = resolveOptions(options); |
| 64 | |
| 65 | const promises: [Promise<T[]>, Promise<number> | undefined] = [ |
| 66 | model |
| 67 | .find(condition) |
| 68 | .skip(limit * (page - 1)) |
| 69 | .limit(limit) |
| 70 | .populate(populate) |
| 71 | .sort(sort), |
| 72 | model.countDocuments(condition), |
| 73 | ]; |
| 74 | |
| 75 | const [items, total] = await Promise.all(promises); |
| 76 | |
| 77 | return createPaginationObject<T>({ |
| 78 | items, |
| 79 | totalItems: total, |
| 80 | currentPage: page, |
| 81 | limit, |
| 82 | }); |
| 83 | } |
| 84 |