[MESOS-7786] Create a special "no sender" PID.

• Type: Improvement
• Status: Reviewable
• Priority: Major
• Resolution: Unresolved
• Component/s: libprocess
• Assignee: Unassigned
• Reporter: Yan Xu
• Created: 12/Jul/17 20:10
• Updated: 17/Jul/17 23:20

Description

In libprocess we have this "fire and forget" messaging semantics with process::post (e.g., MESOS-7753 and a few places in tests).

Right now these kind of messages use an empty sender PID, i.e., @0.0.0.0:0 which is could fail some checks like MESOS-7401.

At a high level I think

• It's OK if libprocess messages don't have a sender actor, akin to the no-sender concept in Akka.
• However all remote messages should have a valid source address i.e., ip and port in its Libprocess-From.

So we can create a special no-sender ID and just make sure real actors can't use this ID. The ID could __no_sender__ or simply _? The UPID would then look like _@192.168.1.2:5050.

Issue Links

• is related to: MESOS-7753 `log.LearnedMessage` could be rejected due to being sent from '@0.0.0.0:0'