PusherBroadcaster.php

TLDR

The PusherBroadcaster.php file is a part of the Illuminate\Broadcasting\Broadcasters namespace in the Laravel framework's Broadcasting package. It extends the Broadcaster class and provides the functionality to broadcast events using the Pusher service. The file contains the PusherBroadcaster class, which includes methods for resolving authenticated users, authenticating incoming requests, broadcasting events, and handling Pusher responses.

Methods

resolveAuthenticatedUser

This method resolves the authenticated user payload for an incoming connection request. It checks if the user is authenticated by calling the resolveAuthenticatedUser method of the parent class. If the authenticateUser method exists in the Pusher instance, it calls that method with the socket ID and user object. Otherwise, it generates the authentication data by hashing the socket ID, user data, and secret key.

auth

This method authenticates the incoming request for a given channel. It checks if the channel name is empty or if the channel is guarded and the user cannot be retrieved. If either condition is true, an AccessDeniedHttpException is thrown. Otherwise, it calls the verifyUserCanAccessChannel method of the parent class.

validAuthenticationResponse

This method returns the valid authentication response for a given request and result. If the channel name starts with "private," it decodes the Pusher response using the decodePusherResponse method. Otherwise, it normalizes the channel name and retrieves the user object. It then generates the authentication response using either the authorizePresenceChannel or presence_auth methods of the Pusher instance.

decodePusherResponse

This protected method decodes the given Pusher response. If the request does not have a callback, it returns the decoded response as an array. Otherwise, it returns a JSON response with the decoded response and the request's callback.

broadcast

This method broadcasts the given event to the specified channels using the Pusher service. It chunks the channels into groups of 100 and triggers the event using the trigger method of the Pusher instance. If an ApiErrorException occurs, it throws a BroadcastException with the corresponding error message.

getPusher

This method returns the Pusher SDK instance used for broadcasting.

setPusher

This method sets the Pusher SDK instance used for broadcasting.

<?php

namespace Illuminate\Broadcasting\Broadcasters;

use Illuminate\Broadcasting\BroadcastException;
use Illuminate\Support\Arr;
use Illuminate\Support\Collection;
use Pusher\ApiErrorException;
use Pusher\Pusher;
use Symfony\Component\HttpKernel\Exception\AccessDeniedHttpException;

class PusherBroadcaster extends Broadcaster
{
    use UsePusherChannelConventions;

    /**
     * The Pusher SDK instance.
     *
     * @var \Pusher\Pusher
     */
    protected $pusher;

    /**
     * Create a new broadcaster instance.
     *
     * @param  \Pusher\Pusher  $pusher
     * @return void
     */
    public function __construct(Pusher $pusher)
    {
        $this->pusher = $pusher;
    }

    /**
     * Resolve the authenticated user payload for an incoming connection request.
     *
     * See: https://pusher.com/docs/channels/library_auth_reference/auth-signatures/#user-authentication
     * See: https://pusher.com/docs/channels/server_api/authenticating-users/#response
     *
     * @param  \Illuminate\Http\Request  $request
     * @return array|null
     */
    public function resolveAuthenticatedUser($request)
    {
        if (! $user = parent::resolveAuthenticatedUser($request)) {
            return;
        }

        if (method_exists($this->pusher, 'authenticateUser')) {
            return $this->pusher->authenticateUser($request->socket_id, $user);
        }

        $settings = $this->pusher->getSettings();
        $encodedUser = json_encode($user);
        $decodedString = "{$request->socket_id}::user::{$encodedUser}";

        $auth = $settings['auth_key'].':'.hash_hmac(
            'sha256', $decodedString, $settings['secret']
        );

        return [
            'auth' => $auth,
            'user_data' => $encodedUser,
        ];
    }

    /**
     * Authenticate the incoming request for a given channel.
     *
     * @param  \Illuminate\Http\Request  $request
     * @return mixed
     *
     * @throws \Symfony\Component\HttpKernel\Exception\AccessDeniedHttpException
     */
    public function auth($request)
    {
        $channelName = $this->normalizeChannelName($request->channel_name);

        if (empty($request->channel_name) ||
            ($this->isGuardedChannel($request->channel_name) &&
            ! $this->retrieveUser($request, $channelName))) {
            throw new AccessDeniedHttpException;
        }

        return parent::verifyUserCanAccessChannel(
            $request, $channelName
        );
    }

    /**
     * Return the valid authentication response.
     *
     * @param  \Illuminate\Http\Request  $request
     * @param  mixed  $result
     * @return mixed
     */
    public function validAuthenticationResponse($request, $result)
    {
        if (str_starts_with($request->channel_name, 'private')) {
            return $this->decodePusherResponse(
                $request,
                method_exists($this->pusher, 'authorizeChannel')
                    ? $this->pusher->authorizeChannel($request->channel_name, $request->socket_id)
                    : $this->pusher->socket_auth($request->channel_name, $request->socket_id)
            );
        }

        $channelName = $this->normalizeChannelName($request->channel_name);

        $user = $this->retrieveUser($request, $channelName);

        $broadcastIdentifier = method_exists($user, 'getAuthIdentifierForBroadcasting')
                        ? $user->getAuthIdentifierForBroadcasting()
                        : $user->getAuthIdentifier();

        return $this->decodePusherResponse(
            $request,
            method_exists($this->pusher, 'authorizePresenceChannel')
                ? $this->pusher->authorizePresenceChannel($request->channel_name, $request->socket_id, $broadcastIdentifier, $result)
                : $this->pusher->presence_auth($request->channel_name, $request->socket_id, $broadcastIdentifier, $result)
        );
    }

    /**
     * Decode the given Pusher response.
     *
     * @param  \Illuminate\Http\Request  $request
     * @param  mixed  $response
     * @return array
     */
    protected function decodePusherResponse($request, $response)
    {
        if (! $request->input('callback', false)) {
            return json_decode($response, true);
        }

        return response()->json(json_decode($response, true))
                    ->withCallback($request->callback);
    }

    /**
     * Broadcast the given event.
     *
     * @param  array  $channels
     * @param  string  $event
     * @param  array  $payload
     * @return void
     *
     * @throws \Illuminate\Broadcasting\BroadcastException
     */
    public function broadcast(array $channels, $event, array $payload = [])
    {
        $socket = Arr::pull($payload, 'socket');

        $parameters = $socket !== null ? ['socket_id' => $socket] : [];

        $channels = Collection::make($this->formatChannels($channels));

        try {
            $channels->chunk(100)->each(function ($channels) use ($event, $payload, $parameters) {
                $this->pusher->trigger($channels->toArray(), $event, $payload, $parameters);
            });
        } catch (ApiErrorException $e) {
            throw new BroadcastException(
                sprintf('Pusher error: %s.', $e->getMessage())
            );
        }
    }

    /**
     * Get the Pusher SDK instance.
     *
     * @return \Pusher\Pusher
     */
    public function getPusher()
    {
        return $this->pusher;
    }

    /**
     * Set the Pusher SDK instance.
     *
     * @param  \Pusher\Pusher  $pusher
     * @return void
     */
    public function setPusher($pusher)
    {
        $this->pusher = $pusher;
    }
}