feat(mainnet): add gov: collective, membership, motion

[peterwht]

Adds a Council based governance that:

• Has NO elections (selected councillors, to start)
• Han NO membership pallet.
• Uses pallet-motion to allow council to use Root origin.

---

• Relevant configuration:

• AtLeastThreeFourthsOfCouncil: at least 3/4 * total seats are aye votes.

• UnanimousCouncilVote: 100% of the votes are aye votes.

• pallet_collective

type DefaultVote = MoreThanMajorityThenPrimeDefaultVote;
type DisapproveOrigin = EnsureRoot<AccountId>;
type KillOrigin = EnsureRoot<AccountId>;
type SetMembersOrigin = EnsureRoot<AccountId>; // <-- This is the only way to modify the members of council.

• pallet_motion

This pallet is how for the council achieves dispatch with Root origin.

// Simple majority is disabled.
type SimpleMajorityOrigin = NeverEnsureOrigin<()>;
// At least 3/4 of the council vote is needed.
type SuperMajorityOrigin = AtLeastThreeFourthsOfCouncil;
// A unanimous council vote is needed.
type UnanimousOrigin = UnanimousCouncilVote;

To familiarize yourself with this governance mechanism, please use the following guide.

Guide

Goal Checklist

• Create a Motion that requires Root
  • Vote on Motion
  • Execute Motion

Create a Motion that requires Root

1. Launch chain pop up parachain -f networks/mainnet.toml
2. Navigate to Council page and note Members
3. Navigate to sub-page for Motions
4. Press "Propose Motion"
5. Min threshold is currently 1/2 + 1. I recommend setting threshold to 4 (unanimous)
6. Set the proposal call to motion.unanimous, providing Root origin
7. Set the sub-call to something that requires Root. One recommendation is to use balances.forceSetBalance
8. You will see a council.Proposed event
9. On the Motions page you will see a new Motion available for vote, along with proposal info
10. Press the Vote button and vote AYE. Repeat this with 4 dev accounts
11. After the threshold is surpassed, the Vote button now changes to Close. Press this button and submit. The proposal is now passed! You will see several events such as council.voted, council.Approved, council.Executed

---

Notes

• One important thing to confirm for ANY governance we choose: do we have to pay DOT to propose a runtime upgrade. This can be costly if so.

• By removing the membership pallet the way to change the members of the council is via dispatching the call council.set_members, which requires Root origin, hence needs to be wrapped in a motion and approved via super majority or unanimous vote.

[peterwht]

[sc-2571]

[al3mart]

Polakdot js apps seems to crash after inputting an external motion 😓 with the expectation of pallet_democracy being present ?

For the record the call I noted as a preimage was balances.forceSetBalance.

I'd assume this is expected as the runtime doesn't feature a way for non council members to cast votes. I think the app will have just wrapped the noted call as a democracy call.
Though is just ugly that the app presents that message.

[al3mart]

The inclusion of these seemed like a sensible choice. Provides a little better UX for the accounts voting on the motions.

Also seems more flexible looking ahead.

[peterwht]

[sc-2200]

[AlexD10S]

The step-by-step guide in the PR description is great. I've been testing and looks good 👌

[al3mart]

I have applied the feedback in this thread.

Introducing a more strict configuration in: 25029be
And adding configuration tests in: 78e9e79

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 94.39868% with 34 lines in your changes missing coverage. Please review.

Project coverage is 74.28%. Comparing base (168cf85) to head (8ba715f).
Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
pallets/motion/src/weights.rs	50.00%	21 Missing ⚠️
node/src/chain_spec.rs	0.00%	7 Missing ⚠️
pallets/motion/src/lib.rs	82.14%	3 Missing and 2 partials ⚠️
pallets/motion/src/benchmarking.rs	85.71%	0 Missing and 1 partial ⚠️

@@            Coverage Diff             @@
##             main     #448      +/-   ##
==========================================
+ Coverage   73.50%   74.28%   +0.78%     
==========================================
  Files          78       84       +6     
  Lines       15696    16301     +605     
  Branches    15696    16301     +605     
==========================================
+ Hits        11538    12110     +572     
- Misses       3897     3927      +30     
- Partials      261      264       +3     

Files with missing lines	Coverage Δ
pallets/motion/src/mock.rs	100.00% <100.00%> (ø)
pallets/motion/src/tests.rs	100.00% <100.00%> (ø)
runtime/mainnet/src/config/governance.rs	100.00% <100.00%> (ø)
runtime/mainnet/src/lib.rs	81.37% <ø> (ø)
pallets/motion/src/benchmarking.rs	85.71% <85.71%> (ø)
pallets/motion/src/lib.rs	82.14% <82.14%> (ø)
node/src/chain_spec.rs	9.96% <0.00%> (-0.21%)	⬇️
pallets/motion/src/weights.rs	50.00% <50.00%> (ø)

... and 1 file with indirect coverage changes

[peterwht]

Thanks for taking this on!

I left a few comments -- biggest one about the min origin required for root.

In a separate PR (maybe with the genesis config presets), I think it would make our lives easier to have a Dev version of mainnet so we can use the dev accounts. Just noting for later.

FYI: I can't approve this PR as I am the original author.

[evilrobot-01]

Saw that prior comments were never submitted, so submitting now in case they are helpful.

[Daanvdplas]

LGTM!

[evilrobot-01]

High level review only, with various suggestions which is left up to author to decide on whether they should be addressed or not.

Note: did not look at any of the tests.

[evilrobot-01]

Seems good to me. I have not looked at the tests or config in any detail so would not be comfortable giving it an approval.

Great work in gettting it all neatened up and ready for prime time!

[Daanvdplas]

LGTM!

[al3mart]

Note that I've pushed some of the changes here, this is an approval after a review from @peterwht to my changes.