Add a method to start a new session

[bogaert]

Sessionization is now purely based on time since the last event. We could add a method that, if called, resets the session ID and increments the session index.

Possible use cases:

• a user switches accounts
• a user completes a purchase and returns to the homepage

See also: snowplow/snowplow-ios-tracker#290

[alexanderdean]

Christophe Bogaert (@bogaert) can you provide a little more information for Mike on this?

[alexanderdean]

Nudge Christophe Bogaert (@bogaert)

[bogaert]

We got this request once or twice from a user. Right now, we start a new session if the last event was 30 or more minutes ago (i.e. when the session cookie has expired). However, there are cases when a user of Snowplow might want to expire a session sooner. For instance, when a user completes a transaction and returns to the homepage, one could consider the previous session complete. When the user returns to the homepage (or continues to any other page), this would start a new session, reflecting that the user has completed the previous unit of work, and is starting a new one.

I hope this explanation makes sense!

I don't think there's need for this to be in 2.9.0 though, given that there's been little user demand. I think server-side sessionization is the better approach in these cases.

[alexanderdean]

Cool, it's not a biggie so we will probably just include it as an easy add.