Add altruistic broadcast to slasher

[michaelsproul]

Description

Presently the Lighthouse slasher is like a greedy dragon, hoarding all of its precious slashings in the Lighthouse op pool and never sharing them with the rest of the network. We should add a flag like --slasher-broadcast or --slasher-altruistic that enables broadcasting attestations for the health of the kingdom network.

Version

v1.0.3

[AgeManning]

The other question is what should be the default behaviour?

I'm down for leaving the selfish option the default until a whistleblower index gets included

[michaelsproul]

Agree, I'm quite fond of the selfish behaviour because I think it incentives more users to run slashers, which is a net win

[paulhauner]

I'm also in favor of greedy as the default. I think it encourages more slashers on the network, whilst still allowing concerned entities to be altruistic.

Another, more complex option would be to switch on eth1_chain.is_some():

• true: we probably have stakers. Keep slashings private unless --broadcast-slashings true.
• false: probably no stakers. Publish slashings unless --broadcast-slashings false.

I'm not convinced the more complex version is worth it though, I prefer a single opt-in flag.

[michaelsproul]

I'm starting work on this now