nestjs-paginate/src/decorator.ts
2023-02-15 10:16:35 +01:00

82 lines
2.8 KiB
TypeScript

import { createParamDecorator, ExecutionContext } from '@nestjs/common'
import { Request } from 'express'
import { pickBy, Dictionary, isString, mapKeys } from 'lodash'
export interface PaginateQuery {
page?: number
limit?: number
sortBy?: [string, string][]
searchBy?: string[]
search?: string
filter?: { [column: string]: string | string[] }
select?: string[]
path: string
}
const singleSplit = (param: string, res: any[]) => res.push(param)
const multipleSplit = (param: string, res: any[]) => {
const items = param.split(':')
if (items.length === 2) {
res.push(items as [string, string])
}
}
const multipleAndCommaSplit = (param: string, res: any[]) => {
const set = new Set<string>(param.split(','))
set.forEach((item) => res.push(item))
}
function parseParam<T>(queryParam: unknown, parserLogic: (param: string, res: any[]) => void): T[] | undefined {
const res = []
if (queryParam) {
const params = !Array.isArray(queryParam) ? [queryParam] : queryParam
for (const param of params) {
if (isString(param)) {
parserLogic(param, res)
}
}
}
return res.length ? res : undefined
}
export const Paginate = createParamDecorator((_data: unknown, ctx: ExecutionContext): PaginateQuery => {
const request: Request = ctx.switchToHttp().getRequest()
const { query } = request
// Determine if Express or Fastify to rebuild the original url and reduce down to protocol, host and base url
let originalUrl: any
if (request.originalUrl) {
originalUrl = request.protocol + '://' + request.get('host') + request.originalUrl
} else {
originalUrl = request.protocol + '://' + request.hostname + request.url
}
const urlParts = new URL(originalUrl)
const path = urlParts.protocol + '//' + urlParts.host + urlParts.pathname
const searchBy = parseParam<string>(query.searchBy, singleSplit)
const sortBy = parseParam<[string, string]>(query.sortBy, multipleSplit)
const select = parseParam<string>(query.select, multipleAndCommaSplit)
const filter = mapKeys(
pickBy(
query,
(param, name) =>
name.includes('filter.') &&
(isString(param) || (Array.isArray(param) && (param as any[]).every((p) => isString(p))))
) as Dictionary<string | string[]>,
(_param, name) => name.replace('filter.', '')
)
return {
page: query.page ? parseInt(query.page.toString(), 10) : undefined,
limit: query.limit ? parseInt(query.limit.toString(), 10) : undefined,
sortBy,
search: query.search ? query.search.toString() : undefined,
searchBy,
filter: Object.keys(filter).length ? filter : undefined,
select,
path,
}
})