Advanced Real-Time Identity
This domain tests the identity layer that makes real-time personalization trustworthy: MPID lifecycle, identify/login/logout, identity resolution, and server-side identity.
Identity model
Every event is tied to an MPID, mParticle's canonical user key. Identity types include customer ID, email, other, and MPID. A user may remain anonymous until a known identity is supplied. The identify call adds identities to the current user; login transitions to a known user and links prior anonymous activity according to workspace identity settings; logout returns the session to an anonymous state.
Real-time rules
- Call identity APIs before logging events that depend on the user, and wait for the identity callback before using the returned MPID.
- Workspace identity resolution settings decide which identities are resolvable keys, so agree the key (customer ID versus email) before launch.
- IDSync keeps identities aligned across connected systems.
- Server-side events must include an MPID or a resolvable identity, or they create a separate profile.
- Logout does not delete data; it changes the active user context.
Worked example
A user browses anonymously, then logs in. The app calls login with a customer ID. The callback returns the known MPID. Events after that call attribute to that profile; earlier anonymous events link according to identity settings. Logging an event before the callback risks attributing it to the anonymous user.
Traps
- Firing events before identify completes.
- Using different identity keys on client and server.
- Assuming logout erases history.
- Confusing MPID with customer ID in API payloads.