VK Connect

A package for integrating VK Mini Apps with official VK clients for iOS, Android and Web.

Usage

import connect from '@vkontakte/vk-connect';

// Sends event to client
connect.send('VKWebAppInit');

// Subscribes to event, sended by client
connect.subscribe(e => console.log(e));

For use in a browser, include the file dist/index.umd.js and use as follows

<script src="dist/index.umd.js"></script>

<script>
  // Sends event to client
  vkConnect.send('VKWebAppInit');
</script>

API Reference

connect.send(method[, params])

Sends a message to native client and returns the Promise object with response data

Parameters

• method required The VK Connect method
• params optional Message data object

Example

// Sending event to client
connect
  .send('VKWebAppGetEmail')
  .then(data => {
    // Handling received data
    console.log(data.email);
  })
  .catch(error => {
    // Handling an error
  });

You can also use imperative way

try {
  const data = await connect.send('VKWebAppGetEmail');

  // Handling received data
  console.log(data.email);
} catch (error) {
  // Handling an error
}

connect.subscribe(fn)

Subscribes a function to events listening

Parameters

• fn required Function to be subscribed to events

Example

// Subscribing to receiving events
connect.subscribe(event => {
  if (!event.detail) {
    return;
  }

  const { type, data } = event.detail;

  if (type === 'VKWebAppOpenCodeReaderResult') {
    // Reading result of the Code Reader
    console.log(data.code_data);
  }

  if (type === 'VKWebAppOpenCodeReaderFailed') {
    // Catching the error
    console.log(data.error_type, data.error_data);
  }
});

// Sending method
connect.send('VKWebAppOpenCodeReader', {});

connect.unsubscribe(fn)

Unsubscribes a function from events listening

Parameters

• fn required Event subscribed function

Example

const fn = event => {
  // ...
};

// Subscribing
connect.subscribe(fn);

// Unsubscribing
connect.unsubscribe(fn);

connect.supports(method)

Checks if an event is available on the current device

Parameters

• method required The VK Connect method

connect.isWebView()

Returns true if VK Connect is running in mobile app, or false if not

Middleware API

Middlewares are pieces of code that intercept and process data between sending and receiving. Thus, by creating middlewares, you can easily log data, modify data before sending it, talking to an asynchronous API, etc. If you've used Redux, you were also probably already familiar with the concept—a similar is used here.

applyMiddleware(middleware1, ..., middlewareN)

Creates the VK Connect enhancer that applies middleware to the send method. This is handy for a variety of task such as logging every sent event. Returns the VK Connect enhancer applying the middleware.

Parameters

• middlewareN A middleware to be applied

Example

import connect, { applyMiddleware } from '@vkontakte/vk-connect';

// Logs the result of each sent event
const logger = ({ send, subscribe }) => next => async (method, props) => {
  const result = await next(method, props);
  console.log(result);
  return result;
};

const enhancedConnect = applyMiddleware(logger)(connect);