how to get tasks that have a due date from task lists in nodejs Google Tasks API?

Question

in this page there is a nodejs example to get all task lists from Google Tasks. I get it to work and I've been playing around to get the tasks of each task list that have a due date, but i haven't even been able to get all tasks associated to a task list. Is it possible? It should be possible, but how?

I must say that i'm a beginner in nodejs... This is the example:

const fs = require('fs');
const readline = require('readline');
const {google} = require('googleapis');

// If modifying these scopes, delete credentials.json.
const SCOPES = ['https://www.googleapis.com/auth/tasks.readonly'];
const TOKEN_PATH = 'credentials.json';

// Load client secrets from a local file.
fs.readFile('client_secret.json', (err, content) => {
  if (err) return console.log('Error loading client secret file:', err);
  // Authorize a client with credentials, then call the Google Slides API.
  authorize(JSON.parse(content), listTaskLists);
});

/**
 * Create an OAuth2 client with the given credentials, and then execute the
 * given callback function.
 * @param {Object} credentials The authorization client credentials.
 * @param {function} callback The callback to call with the authorized client.
 */
function authorize(credentials, callback) {
  const {client_secret, client_id, redirect_uris} = credentials.installed;
  const oAuth2Client = new google.auth.OAuth2(
      client_id, client_secret, redirect_uris[0]);

  // Check if we have previously stored a token.
  fs.readFile(TOKEN_PATH, (err, token) => {
    if (err) return getNewToken(oAuth2Client, callback);
    oAuth2Client.setCredentials(JSON.parse(token));
    callback(oAuth2Client);
  });
}

/**
 * Get and store new token after prompting for user authorization, and then
 * execute the given callback with the authorized OAuth2 client.
 * @param {google.auth.OAuth2} oAuth2Client The OAuth2 client to get token for.
 * @param {getEventsCallback} callback The callback for the authorized client.
 */
function getNewToken(oAuth2Client, callback) {
  const authUrl = oAuth2Client.generateAuthUrl({
    access_type: 'offline',
    scope: SCOPES,
  });
  console.log('Authorize this app by visiting this url:', authUrl);
  const rl = readline.createInterface({
    input: process.stdin,
    output: process.stdout,
  });
  rl.question('Enter the code from that page here: ', (code) => {
    rl.close();
    oAuth2Client.getToken(code, (err, token) => {
      if (err) return callback(err);
      oAuth2Client.setCredentials(token);
      // Store the token to disk for later program executions
      fs.writeFile(TOKEN_PATH, JSON.stringify(token), (err) => {
        if (err) console.error(err);
        console.log('Token stored to', TOKEN_PATH);
      });
      callback(oAuth2Client);
    });
  });
}

/**
 * Lists the user's first 10 task lists.
 *
 * @param {google.auth.OAuth2} auth An authorized OAuth2 client.
 */
function listTaskLists(auth) {
  const service = google.tasks({version: 'v1', auth});
  service.tasklists.list({
    maxResults: 10,
  }, (err, res) => {
    if (err) return console.error('The API returned an error: ' + err);
    const taskLists = res.data.items;
    if (taskLists) {
      console.log('Task lists:');
      taskLists.forEach((taskList) => {
        console.log(`${taskList.title} (${taskList.id})`);
      });
    } else {
      console.log('No task lists found.');
    }
  });
}

Answer 1

In the example, to get all tasks list from Google Tasks, you are using the function service.tasklists.list.

Then you need to get the id from every tasklist returned and call the function service.tasks.list with id from tasklists as parameter. Something like:

function getTasksFromTaskList(tasklistid, auth) {
  const service = google.tasks({version: 'v1', auth});
  service.tasks.list({
    tasklist: tasklistid,
  }, (err, res) => {
    if (err) return console.error('The API returned an error: ' + err);
    const tasks = res.data.items;
    if (tasks) {
      console.log(`Tasks from ${tasklistid}:`);
      tasks.forEach((task) => {
        console.log(`${task.title} (${task.id})`);
      });
    } else {
      console.log('No tasks found.');
    }
  });
}

You will find more information in the API reference: https://developers.google.com/tasks/v1/reference/tasks/list.

As you can see on that link, you can include more optional parameters in the request (for example, due date).