Accessing userid and channel type from the dialog flow and custom component

Summary

I am looking ofr a proper way to access user information and channel information

Content

Hi,

I am looking for a proper way to access user information and channel information, from both Dialog Flow and Custom Component.

My Bot is running on 3 different channels ( Alexa, Facebook Messenger, Website) and i would like :

1) to have a switch proposing various options based on the invoking channel, thus my need to acces the channel type from the dialog flow. I have tried many things (channelType ... ) but nothing worked out. Same when trying to access it from a custom component.

2) to have acess to userId, so i can access and store data. in the custom component i have tried