66 lines
1.6 KiB
TypeScript
66 lines
1.6 KiB
TypeScript
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// common/utils/pagination/pagination.service.ts
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import { PaginationOptions, PaginationParams, PaginatedResponse } from './pagination.types';
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export class PaginationService {
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private readonly DEFAULT_PAGE = 1;
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private readonly DEFAULT_LIMIT = 10;
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private readonly MAX_LIMIT = 100;
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/**
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* Parse and validate pagination parameters
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*/
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parsePaginationParams(params: PaginationParams): PaginationOptions {
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let page = Number(params.page) || this.DEFAULT_PAGE;
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let limit = Number(params.limit) || this.DEFAULT_LIMIT;
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// Validate and constrain values
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page = Math.max(1, page);
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limit = Math.max(1, Math.min(limit, this.MAX_LIMIT));
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const skip = (page - 1) * limit;
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return {
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page,
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limit,
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skip,
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};
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}
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/**
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* Create paginated response
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*/
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createPaginatedResponse<T>(
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data: T[],
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totalCount: number,
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paginationOptions: PaginationOptions,
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): PaginatedResponse<T> {
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const { page, limit } = paginationOptions;
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const totalPages = Math.ceil(totalCount / limit);
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return {
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data,
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pagination: {
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currentPage: page,
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pageSize: limit,
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totalCount,
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totalPages,
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hasNext: page < totalPages,
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hasPrevious: page > 1,
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},
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};
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}
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/**
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* Extract pagination params from API Gateway event
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*/
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getPaginationFromEvent(event: any): PaginationParams {
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const queryParams = event.queryStringParameters || {};
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return {
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page: queryParams.page,
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limit: queryParams.limit,
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};
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}
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}
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export const paginationService = new PaginationService();
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