api.js

import axios from 'axios';

let instance = axios.create();
instance.defaults.baseURL = 'xxx.teamwork.com'
instance.defaults.headers.common['Authorization'] = 'Bearer XXX';

export default instance;

tasks.js

import api from './api';

const defaultParams = {
  page: 1,
  pageSize: 10,
};

const normalizeV1Pagination = (headers) => ({
  page: parseInt(headers['x-page'], 10),
  pages: parseInt(headers['x-pages'], 10),
  totalRecords: parseInt(headers['x-records'], 10),
});

const normalizeV1Cache = (headers) => ({
  etag: headers['etag'],
});

const normalizeV2Data = (data) => data;

const normalizeV1Data = (data) => data.map((task) => ({
  title: task.content,
  description: task.description,
  assignee: task['responsible-party-names'] || 'Anybody',
}));

const normalizeV2Headers = (headers) => headers;

const serializeParams = (params = {}) => ({
  ...defaultParams,
  ...params,
});

const fetch = {
  'v1': async (params = { id: 0 }) => {
    try {
      const { data, headers } = await api.get(`projects/${params.id}/tasks.json`, {
        params: serializeParams(params)
      });
      if (data.STATUS === "OK") {
        return {
          data: normalizeV1Data(data['todo-items']),
          paginator: normalizeV1Pagination(headers),
          cache: normalizeV1Cache(headers),
        };
      }
    } catch (err) {
      throw new Error(err);
    }
  },
  'v2': async (params = { id: 0 }) => {
    try {
      const { data, headers, status } = await api.get(`/projects/api/v2/projects/${params.id}/taskids.json`, {
        data: serializeParams(params)
      });
      if (status === 200) {
        return {
          data: normalizeV2Data(data.project),
          paginator: normalizeV2Headers(headers),
          cache: normalizeV1Cache(headers),
        };
      }
    } catch (err) {
      throw new Error(err);
    }
  }
};

export default async (params, options = { version: 'v1' }) => {
  return fetch[options.version](params);
};

tasks.test.js

import test from 'ava';
import getTasksByProject from './tasks';

test('respectful page size', async (t) => {
  const tasks = await getTasksByProject({ id: 422481, pageSize: 10 });
	t.is(tasks.data.length, 10);
});

test('working paginator', async (t) => {
  const page1 = await getTasksByProject({ id: 422481, page: 1, pageSize: 15 });
  const page2 = await getTasksByProject({ id: 422481, page: 2, pageSize: 15 });

  const tasks = [
    ...page1.data,
    ...page2.data,
  ];
  t.is(page1.paginator.page, 1);
  t.is(page2.paginator.page, 2);
  t.is(tasks.length, 30);
});

test('normalised data', async (t) => {
  const page1 = await getTasksByProject({ id: 422481, page: 1, pageSize: 15 });

  t.deepEqual(Object.keys(page1.data[0]), ['title', 'description', 'assignee']);
  t.deepEqual(Object.keys(page1.paginator), ['page', 'pages', 'totalRecords']);
});