Add voting power cap during snapshot (#135)

* Process snapshot to output VoterHIR

Use VoterHIR as the output format for the snapshot
tool

* revert vp cap

* add proptest implementation for VoterHIR

* Add cap for voting influence in snapshot

Limit overall influence of actors in an election by capping their
maximum voting power at arbitrary levels.

Since a lot of configurations are going in the snapshot process,
I'm thinking of having it output two different artifacts:
the list of VoterHIRs, as already proposed, and another one which
is a light wrapper around VoterHIR which contains contributions
from snapshot, to be used for the reward process.

I'm proposing to keep the separate because the first one is
more general, while the second one is tied to our current
deployment and more likely to change.

* update doc comment

* add missing import

* pin Fraction to 0.10

* address review comments

Author: zeegomo

Cargo.lock

@@ -61,6 +61,7 @@ gag = "1"
 vit-servicing-station-lib = { git = "https://github.com/input-output-hk/vit-servicing-station.git", branch = "master" }
 env_logger = "0.9"
 voting-hir = { path = "../voting-hir", features = ["serde"] }
+fraction = "0.10"
 
 [dev-dependencies]
 rand_chacha = "0.3"
@@ -71,6 +72,7 @@ chain-vote = { git = "https://github.com/input-output-hk/chain-libs.git", branch
 proptest = { git = "https://github.com/input-output-hk/proptest", branch = "master" }
 test-strategy = "0.2"
 serde_test = "1"
+voting-hir =  { path = "../voting-hir", features = ["serde", "proptest"] }
 
 [build-dependencies]
 versionisator = "1.0.3"

catalyst-toolbox/Cargo.toml

@@ -1,11 +1,13 @@
 use catalyst_toolbox::rewards::voters::{calc_voter_rewards, Rewards, VoteCount};
-use catalyst_toolbox::snapshot::{registration::MainnetRewardAddress, Snapshot};
+use catalyst_toolbox::snapshot::{
+    registration::MainnetRewardAddress, voting_group::VotingGroupAssigner, Snapshot,
+};
 use catalyst_toolbox::utils::assert_are_close;
 
 use color_eyre::Report;
+use fraction::Fraction;
 use jcli_lib::jcli_lib::block::Common;
-use jormungandr_lib::interfaces::Block0Configuration;
-
+use jormungandr_lib::{crypto::account::Identifier, interfaces::Block0Configuration};
 use structopt::StructOpt;
 
 use std::collections::BTreeMap;
@@ -30,6 +32,10 @@ pub struct VotersRewards {
     #[structopt(long)]
     registration_threshold: u64,
 
+    /// Voting power cap for each account
+    #[structopt(short, long)]
+    voting_power_cap: Fraction,
+
     #[structopt(long)]
     votes_count_path: PathBuf,
 
@@ -64,6 +70,7 @@ impl VotersRewards {
             registration_threshold,
             votes_count_path,
             vote_threshold,
+            voting_power_cap,
         } = self;
         let block = common.input.load_block()?;
         let block0 = Block0Configuration::from_block(&block)?;
@@ -75,7 +82,9 @@ impl VotersRewards {
         let snapshot = Snapshot::from_raw_snapshot(
             serde_json::from_reader(jcli_lib::utils::io::open_file_read(&Some(snapshot_path))?)?,
             registration_threshold.into(),
-        );
+            voting_power_cap,
+            &DummyAssigner,
+        )?;
 
         let results = calc_voter_rewards(
             vote_count,
@@ -92,3 +101,10 @@ impl VotersRewards {
         Ok(())
     }
 }
+
+struct DummyAssigner;
+impl VotingGroupAssigner for DummyAssigner {
+    fn assign(&self, _vk: &Identifier) -> String {
+        unimplemented!()
+    }
+}

catalyst-toolbox/src/bin/cli/rewards/voters.rs

@@ -1,13 +1,14 @@
 use catalyst_toolbox::snapshot::{voting_group::RepsVotersAssigner, RawSnapshot, Snapshot};
 use color_eyre::Report;
+use fraction::Fraction;
 use jcli_lib::utils::{output_file::OutputFile, output_format::OutputFormat};
 use jormungandr_lib::interfaces::Value;
 use std::fs::File;
 use std::io::Write;
 use std::path::PathBuf;
 use structopt::StructOpt;
 
-const DEFAULT_DIRECT_VOTER_GROUP: &str = "voter";
+const DEFAULT_DIRECT_VOTER_GROUP: &str = "direct";
 const DEFAULT_REPRESENTATIVE_GROUP: &str = "rep";
 
 /// Process raw registrations into blockchain initials
@@ -35,6 +36,10 @@ pub struct SnapshotCmd {
     #[structopt(long)]
     reps_db_api_url: reqwest::Url,
 
+    /// Voting power cap for each account
+    #[structopt(short, long)]
+    voting_power_cap: Fraction,
+
     #[structopt(flatten)]
     output: OutputFile,
 
@@ -52,8 +57,13 @@ impl SnapshotCmd {
             .representatives_group
             .unwrap_or_else(|| DEFAULT_REPRESENTATIVE_GROUP.into());
         let assigner = RepsVotersAssigner::new(direct_voter, representative, self.reps_db_api_url)?;
-        let initials =
-            Snapshot::from_raw_snapshot(raw_snapshot, self.threshold).to_voter_hir(&assigner);
+        let initials = Snapshot::from_raw_snapshot(
+            raw_snapshot,
+            self.threshold,
+            self.voting_power_cap,
+            &assigner,
+        )?
+        .to_voter_hir();
         let mut out_writer = self.output.open()?;
         let content = self
             .output_format

catalyst-toolbox/src/bin/cli/snapshot/mod.rs

@@ -186,6 +186,7 @@ mod tests {
     use chain_impl_mockchain::chaintypes::ConsensusVersion;
     use chain_impl_mockchain::fee::LinearFee;
     use chain_impl_mockchain::tokens::{identifier::TokenIdentifier, name::TokenName};
+    use fraction::Fraction;
     use jormungandr_lib::crypto::account::Identifier;
     use jormungandr_lib::interfaces::BlockchainConfiguration;
     use jormungandr_lib::interfaces::{Destination, Initial, InitialToken, InitialUTxO};
@@ -338,7 +339,13 @@ mod tests {
             total_stake += i;
         }
 
-        let snapshot = Snapshot::from_raw_snapshot(raw_snapshot.into(), 0.into());
+        let snapshot = Snapshot::from_raw_snapshot(
+            raw_snapshot.into(),
+            0.into(),
+            Fraction::from(1u64),
+            &|_vk: &Identifier| String::new(),
+        )
+        .unwrap();
 
         let initial = snapshot.to_block0_initials(Discrimination::Test);
         let block0 = blockchain_configuration(initial);