=encoding utf-8

=head1 NAME

ngx_stream_mqtt_preread_module - Module ngx_stream_mqtt_preread_module




=head1



The C<ngx_stream_mqtt_preread_module> module (1.23.4) allows
extracting information from the CONNECT message
of the Message Queuing Telemetry Transport protocol (MQTT) versions
L<3.1.1|https://docs.oasis-open.org/mqtt/mqtt/v3.1.1/mqtt-v3.1.1.html>
and
L<5.0|https://docs.oasis-open.org/mqtt/mqtt/v5.0/mqtt-v5.0.html>,
for example, a username or a client ID.






B<NOTE>

This module is available as part of our
commercial subscription.





=head1 Example Configuration




    
    mqtt_preread on;
    return       $mqtt_preread_clientid;






=head1 Directives

=head2 mqtt_preread


B<syntax:> mqtt_preread I<C<on> E<verbar> C<off>>


B<default:> I<off>


B<context:> I<stream>


B<context:> I<server>





Enables extracting information from the MQTT CONNECT message at
the L<preread|stream_processing> phase.







=head1 Embedded Variables




=over



=item C<$mqtt_preread_clientid>




the C<clientid> value from the CONNECT message



=item C<$mqtt_preread_username>




the C<username> value from the CONNECT message




=back