pagination - wip

apps/server/src/helpers/pagination/paginated-result.ts

@@ -0,0 +1,14 @@
+import { IsArray } from 'class-validator';
+import { PaginationMetaDto } from './pagination-meta-dto';
+
+export class PaginatedResult<T> {
+  @IsArray()
+  readonly items: T[];
+
+  readonly pagination: PaginationMetaDto;
+
+  constructor(items: T[], pagination: PaginationMetaDto) {
+    this.items = items;
+    this.pagination = pagination;
+  }
+}

apps/server/src/helpers/pagination/pagination-meta-dto.ts

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+import { PaginationOptions } from './pagination-options';
+
+export class PaginationMetaDto {
+  readonly page: number;
+
+  readonly limit: number;
+
+  readonly total: number;
+
+  readonly pageCount: number;
+
+  readonly hasPreviousPage: boolean;
+
+  readonly hasNextPage: boolean;
+
+  constructor({ count, paginationOptions }: PageMetaDtoParameters) {
+    this.page = paginationOptions.page;
+    this.limit = paginationOptions.limit;
+    this.total = count;
+    this.pageCount = Math.ceil(this.total / this.limit);
+    this.hasPreviousPage = this.page > 1;
+    this.hasNextPage = this.page < this.pageCount;
+  }
+}
+
+export interface PageMetaDtoParameters {
+  count: number;
+  paginationOptions: PaginationOptions;
+}

apps/server/src/helpers/pagination/pagination-options.ts

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+import { IsNumber, IsOptional, IsPositive, Max, Min } from 'class-validator';
+
+export class PaginationOptions {
+  @IsOptional()
+  @IsNumber()
+  @Min(1)
+  page = 1;
+
+  @IsOptional()
+  @IsNumber()
+  @IsPositive()
+  @Min(1)
+  @Max(100)
+  limit = 25;
+
+  @IsOptional()
+  @IsNumber()
+  offset = 0;
+
+  get skip(): number {
+    return (this.page - 1) * this.limit;
+  }
+}