feat(api): add parsePaginationParams helper

package.json

@@ -49,6 +49,7 @@
     "pg": "^8.12.0",
     "pino": "^8.6.1",
     "pino-pretty": "^9.1.0",
+    "qs": "^6.13.0",
     "redis": "^4.7.0",
     "reflect-metadata": "^0.2.2",
     "zod": "^3.23.8"
@@ -67,6 +68,7 @@
     "@types/jest": "^29.5.12",
     "@types/lodash": "^4.17.6",
     "@types/node": "^20.8.6",
+    "@types/qs": "^6.9.15",
     "@types/superagent": "^8.1.8",
     "@types/supertest": "^6.0.2",
     "@types/uuid": "^10.0.0",

src/utils/__tests__/parsePaginationParams.test.ts

@@ -0,0 +1,41 @@
+import parsePaginationParams from '../parsePaginationParams';
+
+describe('parsePaginationParams', () => {
+  test('should parse valid page and pageSize as numbers', () => {
+    const query = {
+      page: '2',
+      pageSize: '10',
+    };
+
+    const result = parsePaginationParams(query);
+    expect(result).toEqual({
+      page: 2,
+      pageSize: 10,
+    });
+  });
+
+  test('should turn negative numbers into the default paging', () => {
+    const query = {
+      page: '-1',
+      pageSize: '-11111110',
+    };
+
+    const result = parsePaginationParams(query);
+    expect(result).toEqual({
+      page: 1,
+      pageSize: 10,
+    });
+  });
+
+  test('should return undefined for empty query', () => {
+    const query = {};
+    const result = parsePaginationParams(query);
+    expect(result).toEqual({ page: undefined, pageSize: undefined });
+  });
+
+  test('should return undefined for invalid page and pageSize', () => {
+    const query = { page: 'abc', pageSize: 'xyz' };
+    const result = parsePaginationParams(query);
+    expect(result).toEqual({ page: undefined, pageSize: undefined });
+  });
+});

src/utils/parsePaginationParams.ts

@@ -0,0 +1,43 @@
+import type { ParsedQs } from 'qs';
+
+interface PaginationParams {
+  page?: number;
+  pageSize?: number;
+}
+
+export default function parsePaginationParams(
+  query: ParsedQs,
+): PaginationParams {
+  let page: number | undefined;
+  let pageSize: number | undefined;
+
+  if (
+    typeof query.page === 'number' ||
+    (typeof query.page === 'string' && isInt(query.page))
+  ) {
+    page = Number(query.page);
+    if (page < 1) {
+      page = 1;
+    }
+  }
+
+  if (
+    typeof query.pageSize === 'number' ||
+    (typeof query.pageSize === 'string' && isInt(query.pageSize))
+  ) {
+    pageSize = Number(query.pageSize);
+    if (pageSize < 1) {
+      pageSize = 10;
+    }
+  }
+
+  return {
+    page,
+    pageSize,
+  };
+}
+
+function isInt(value: string): boolean {
+  const number = Number(value);
+  return !Number.isNaN(number) && Number.isInteger(number);
+}