Exposing event request in interaction handler

[Vladmel1234]

Hey i in order to present error messages in View in need to preform Ack to the raw event with Error payload https://api.slack.com/surfaces/modals#displaying_errors In order to do it properly i need request inside interaction handler this issue will be follow by PR

there is open PR https://github.com/slack-io/slacker/pull/19 that doing this but it looks like it wont be merged soon because of fix requests i am opening one with requests fulfilled in case you prefer to merge original one i am more than fine with it but it looks like its in stale state

[0xArch3r]

This event request is also needed if you want to use the external api feature to populate like the dropdown searches etc.