make topology view edges more useful

[rade]

Edges in the topology view are presently very underutilised. We could hang some additional info and controls off them.

Some ideas...

1. show IPs and ports on hover
2. gather/show network level metrics
3. show L7 metrics (see L7 metrics #1631)

[rade]

I am guessing that (1) could be accomplished purely in the UI. Correct @davkal @foot ?

[jpellizzari]

I have some concepts ready for design feedback:

https://docs.google.com/presentation/d/1AHfwIn2PZtYmpt4XEEiWhnCN77CUaLR-BnZstiLBQNo/edit

@2opremio, @ekimekim , @davkal , @foot , @bowenli, @fbarl please feel free to leave comments

[jpellizzari]

The consensus from the feedback was to use arrows to indicate connection relationships, and to arrange nodes in the 'node details' view with client connections on top, and server connections on bottom (slide 3 reversed).

[jpellizzari]

First pass at arrows:

[rade]

Nice!

This is for the radial "node selected" view, right? In that view, I think it would be helpful to try to orient the flow from top to bottom, as suggested in #875 (though still placing nodes at equal distance on a circle, perhaps leaving a gap between inbound, inbound+outbound, outbound; this does mean some flows can point in the wrong direction, but at least it's not a complete jumble).

Have we decided yet whether to also show arrow-heads on mouseover? I think we should.

[2opremio]

Feature request from real user unaware of this GitHub issue:

Is there a way (or could there be a way) of allowing me to attach
metadata to the edges? A typical tag might be “HTTPS / TLS1.2”, and is
clearly information that Weave wouldn’t know (my assumption, anyway)?

[jpellizzari]

@2opremio I take it we can't know for sure what protocol a connection is using without packet inspection; maybe we can assume protocols based on common ports?

[jpellizzari]

@rade Yes, that is the radial view.

perhaps leaving a gap between inbound, inbound+outbound, outbound;

Yes, I was planning on doing something like that. Using the positions of the nodes to add meaning.

Have we decided yet whether to also show arrow-heads on mouseover?

At the moment, the arrows don't feel too distracting if we just show them all the time (in the radial view).

[rade]

I was talking about mouseover in the main view.

The issue is that you really, really need the arrow heads for disambiguation in the main view. Node selection loses too much context.