Channel start message received handler with support for extended attributes.
In most situations, while using Vortex Library, you can assume the default implementation to handle the start channel request.
However, a start message request could have several attributes and additional parameters that are notified in the form of a "piggyback", to set up new channels, performing especial operations, as happens with TLS negotiation.
This handler allows to get start message notification with all possible data received.
Here is an channel start message example:
<start number='1' serverName='my.domain.com'> <profile uri='http://some-unique-profile-uri/mech' encoding='none'> <![CDATA[some necessary initial round trip data]]> </profile> </start>
This handler will notify the channel number being requested, the serverName value, the profile requested, the piggyback encoding and the optional piggyback.
Keep in mind that the encoding is an implicit attribute. Having it not defined yields to the default value 'none', which is represented by EncodingNone.
Functions using this handler: