chore: moved fee exhaust constant to consensus constants (#1166)

Description
---

Fee exhaust divisor (mainly used to calculate leader fees) was a hard
coded constant and moved to the consensus constants to make it
configurable on a tari network basis (DAN constants - Tari Network
mapping).

Motivation and Context
---
Fee exhaust divisor (mainly used to calculate leader fees) was a simple
hard coded constant before and it should be network specific.

How Has This Been Tested?
---

Checking whether everything is still building and running.

What process can a PR reviewer use to test or verify this change?
---


Breaking Changes
---

- [x] None
- [ ] Requires data directory to be deleted
- [ ] Other - Please specify

applications/tari_dan_app_utilities/Cargo.toml

@@ -11,6 +11,7 @@ tari_common = { workspace = true }
 tari_common_types = { workspace = true }
 tari_core = { workspace = true, default-features = false, features = ["transactions"] }
 tari_crypto = { workspace = true }
+tari_consensus = { workspace = true }
 tari_shutdown = { workspace = true }
 tari_dan_common_types = { workspace = true }
 tari_state_store_sqlite = { workspace = true }

applications/tari_dan_app_utilities/src/base_layer_scanner.rs

@@ -30,6 +30,7 @@ use tari_base_node_client::{
     BaseNodeClientError,
 };
 use tari_common_types::types::{Commitment, FixedHash, FixedHashSizeError, PublicKey};
+use tari_consensus::consensus_constants::ConsensusConstants;
 use tari_core::transactions::{
     tari_amount::MicroMinotari,
     transaction_components::{
@@ -61,10 +62,7 @@ use tari_state_store_sqlite::SqliteStateStore;
 use tari_template_lib::models::{EncryptedData, TemplateAddress, UnclaimedConfidentialOutputAddress};
 use tokio::{task, task::JoinHandle, time};
 
-use crate::{
-    consensus_constants::ConsensusConstants,
-    template_manager::interface::{TemplateManagerError, TemplateManagerHandle, TemplateRegistration},
-};
+use crate::template_manager::interface::{TemplateManagerError, TemplateManagerHandle, TemplateRegistration};
 
 const LOG_TARGET: &str = "tari::dan::base_layer_scanner";
 

applications/tari_dan_app_utilities/src/lib.rs

@@ -22,7 +22,6 @@
 
 pub mod base_layer_scanner;
 pub mod configuration;
-pub mod consensus_constants;
 pub mod json_encoding;
 pub mod keypair;
 pub mod p2p_config;

applications/tari_indexer/Cargo.toml

@@ -28,6 +28,7 @@ tari_indexer_lib = { workspace = true }
 tari_template_lib = { workspace = true }
 tari_transaction = { workspace = true }
 tari_dan_p2p = { workspace = true }
+tari_consensus = { workspace = true }
 tari_validator_node_rpc = { workspace = true }
 tari_rpc_framework = { workspace = true }
 tari_networking = { workspace = true }

applications/tari_indexer/src/bootstrap.rs

@@ -30,10 +30,10 @@ use tari_common::{
     configuration::bootstrap::{grpc_default_port, ApplicationType},
     exit_codes::{ExitCode, ExitError},
 };
+use tari_consensus::consensus_constants::ConsensusConstants;
 use tari_crypto::tari_utilities::ByteArray;
 use tari_dan_app_utilities::{
     base_layer_scanner,
-    consensus_constants::ConsensusConstants,
     keypair::RistrettoKeypair,
     seed_peer::SeedPeer,
     template_manager::{self, implementation::TemplateManager},

applications/tari_indexer/src/event_scanner.rs

@@ -26,8 +26,8 @@ use futures::StreamExt;
 use log::*;
 use tari_bor::decode;
 use tari_common::configuration::Network;
+use tari_consensus::consensus_constants::ConsensusConstants;
 use tari_crypto::{ristretto::RistrettoPublicKey, tari_utilities::message_format::MessageFormat};
-use tari_dan_app_utilities::consensus_constants::ConsensusConstants;
 use tari_dan_common_types::{committee::Committee, Epoch, NumPreshards, PeerAddress, ShardGroup};
 use tari_dan_p2p::proto::rpc::{GetTransactionResultRequest, PayloadResultStatus, SyncBlocksRequest};
 use tari_dan_storage::consensus_models::{Block, BlockError, BlockId, Decision, TransactionRecord};
@@ -101,6 +101,7 @@ pub struct EventScanner {
     client_factory: TariValidatorNodeRpcClientFactory,
     substate_store: SqliteSubstateStore,
     event_filters: Vec<EventFilter>,
+    consensus_constants: ConsensusConstants,
 }
 
 impl EventScanner {
@@ -111,6 +112,7 @@ impl EventScanner {
         client_factory: TariValidatorNodeRpcClientFactory,
         substate_store: SqliteSubstateStore,
         event_filters: Vec<EventFilter>,
+        consensus_constants: ConsensusConstants,
     ) -> Self {
         Self {
             network,
@@ -119,6 +121,7 @@ impl EventScanner {
             client_factory,
             substate_store,
             event_filters,
+            consensus_constants,
         }
     }
 
@@ -476,10 +479,7 @@ impl EventScanner {
 
         let start_block_id = match start_block_id {
             Some(block_id) => block_id,
-            None => {
-                let consensus_constants = ConsensusConstants::from(self.network);
-                self.build_genesis_block_id(consensus_constants.num_preshards)?
-            },
+            None => self.build_genesis_block_id(self.consensus_constants.num_preshards)?,
         };
 
         committee.shuffle();

applications/tari_indexer/src/lib.rs

@@ -51,11 +51,8 @@ use tari_common::{
     configuration::bootstrap::{grpc_default_port, ApplicationType},
     exit_codes::{ExitCode, ExitError},
 };
-use tari_dan_app_utilities::{
-    consensus_constants::ConsensusConstants,
-    keypair::setup_keypair_prompt,
-    substate_file_cache::SubstateFileCache,
-};
+use tari_consensus::consensus_constants::ConsensusConstants;
+use tari_dan_app_utilities::{keypair::setup_keypair_prompt, substate_file_cache::SubstateFileCache};
 use tari_dan_storage::global::DbFactory;
 use tari_dan_storage_sqlite::SqliteDbFactory;
 use tari_epoch_manager::{EpochManagerEvent, EpochManagerReader};
@@ -179,13 +176,15 @@ pub async fn run_indexer(config: ApplicationConfig, mut shutdown_signal: Shutdow
         .map(TryInto::try_into)
         .collect::<Result<_, _>>()
         .map_err(|e| ExitError::new(ExitCode::ConfigError, format!("Invalid event filters: {}", e)))?;
+    let consensus_constants = ConsensusConstants::from(config.network);
     let event_scanner = Arc::new(EventScanner::new(
         config.network,
         config.indexer.sidechain_id,
         Box::new(services.epoch_manager.clone()),
         services.validator_node_client_factory.clone(),
         services.substate_store.clone(),
         event_filters,
+        consensus_constants,
     ));
 
     // Run the GraphQL API

applications/tari_validator_node/src/bootstrap.rs

@@ -34,13 +34,13 @@ use tari_common::{
     configuration::Network,
     exit_codes::{ExitCode, ExitError},
 };
+use tari_consensus::consensus_constants::ConsensusConstants;
 #[cfg(not(feature = "metrics"))]
 use tari_consensus::traits::hooks::NoopHooks;
 use tari_core::transactions::transaction_components::ValidatorNodeSignature;
 use tari_crypto::{ristretto::RistrettoPublicKey, tari_utilities::ByteArray};
 use tari_dan_app_utilities::{
     base_layer_scanner,
-    consensus_constants::ConsensusConstants,
     keypair::RistrettoKeypair,
     seed_peer::SeedPeer,
     substate_file_cache::SubstateFileCache,

applications/tari_validator_node/src/consensus/mod.rs

@@ -8,7 +8,6 @@ use tari_consensus::{
 };
 use tari_crypto::ristretto::RistrettoPublicKey;
 use tari_dan_app_utilities::{
-    consensus_constants::ConsensusConstants,
     template_manager::implementation::TemplateManager,
     transaction_executor::TariDanTransactionProcessor,
 };
@@ -52,6 +51,7 @@ mod spec;
 pub use block_transaction_executor::*;
 pub use handle::*;
 pub use signature_service::*;
+use tari_consensus::consensus_constants::ConsensusConstants;
 
 use crate::{p2p::NopLogger, transaction_validators::WithContext};
 
@@ -84,10 +84,7 @@ pub async fn spawn(
     let hs_config = HotstuffConfig {
         network,
         sidechain_id,
-        max_base_layer_blocks_behind: consensus_constants.max_base_layer_blocks_behind,
-        max_base_layer_blocks_ahead: consensus_constants.max_base_layer_blocks_ahead,
-        num_preshards: consensus_constants.num_preshards,
-        pacemaker_max_base_time: consensus_constants.pacemaker_max_base_time,
+        consensus_constants,
     };
 
     let hotstuff_worker = HotstuffWorker::<TariConsensusSpec>::new(

applications/tari_validator_node/src/lib.rs

@@ -48,7 +48,8 @@ use tari_common::{
     configuration::bootstrap::{grpc_default_port, ApplicationType},
     exit_codes::{ExitCode, ExitError},
 };
-use tari_dan_app_utilities::{consensus_constants::ConsensusConstants, keypair::setup_keypair_prompt};
+use tari_consensus::consensus_constants::ConsensusConstants;
+use tari_dan_app_utilities::keypair::setup_keypair_prompt;
 use tari_dan_common_types::SubstateAddress;
 use tari_dan_storage::global::DbFactory;
 use tari_dan_storage_sqlite::SqliteDbFactory;
@@ -116,13 +117,14 @@ pub async fn run_validator_node(
     #[cfg(feature = "metrics")]
     let metrics_registry = create_metrics_registry(keypair.public_key());
 
+    let consensus_constants = ConsensusConstants::from(config.network);
     let base_node_client = create_base_layer_client(config).await?;
     let services = spawn_services(
         config,
         shutdown_signal.clone(),
         keypair.clone(),
         global_db,
-        ConsensusConstants::devnet(), // TODO: change this eventually
+        consensus_constants,
         base_node_client.clone(),
         #[cfg(feature = "metrics")]
         &metrics_registry,

dan_layer/consensus/src/block_validations.rs

@@ -79,7 +79,7 @@ pub async fn check_base_layer_block_hash<TConsensusSpec: ConsensusSpec>(
     //         current: current_height,
     //     })?;
     // }
-    if base_layer_block_height > current_height + config.max_base_layer_blocks_ahead {
+    if base_layer_block_height > current_height + config.consensus_constants.max_base_layer_blocks_ahead {
         Err(ProposalValidationError::BlockHeightTooHigh {
             proposed: base_layer_block_height,
             current: current_height,

applications/tari_dan_app_utilities/src/consensus_constants.rs → dan_layer/consensus/src/consensus_constants.rs

@@ -33,6 +33,8 @@ pub struct ConsensusConstants {
     pub max_base_layer_blocks_behind: u64,
     pub num_preshards: NumPreshards,
     pub pacemaker_max_base_time: Duration,
+    /// The value that fees are divided by to determine the amount of fees to burn. 0 means no fees are burned.
+    pub fee_exhaust_divisor: u64,
 }
 
 impl ConsensusConstants {
@@ -44,6 +46,7 @@ impl ConsensusConstants {
             max_base_layer_blocks_behind: 5,
             num_preshards: NumPreshards::P256,
             pacemaker_max_base_time: Duration::from_secs(10),
+            fee_exhaust_divisor: 20, // 5%
         }
     }
 }

dan_layer/consensus/src/hotstuff/common.rs

@@ -46,10 +46,6 @@ use crate::{
 
 const LOG_TARGET: &str = "tari::dan::consensus::hotstuff::common";
 
-/// The value that fees are divided by to determine the amount of fees to burn. 0 means no fees are burned.
-/// This is a placeholder for the fee exhaust consensus constant so that we know where it's used later.
-pub const EXHAUST_DIVISOR: u64 = 20; // 5%
-
 /// Calculates the dummy block required to reach the new height and returns the last dummy block (parent for next
 /// proposal).
 pub fn calculate_last_dummy_block<TAddr: NodeAddressable, TLeaderStrategy: LeaderStrategy<TAddr>>(

dan_layer/consensus/src/hotstuff/config.rs

@@ -1,18 +1,14 @@
 //   Copyright 2023 The Tari Project
 //   SPDX-License-Identifier: BSD-3-Clause
 
-use std::time::Duration;
-
 use tari_common::configuration::Network;
 use tari_crypto::ristretto::RistrettoPublicKey;
-use tari_dan_common_types::NumPreshards;
+
+use crate::consensus_constants::ConsensusConstants;
 
 #[derive(Debug, Clone)]
 pub struct HotstuffConfig {
     pub network: Network,
-    pub max_base_layer_blocks_ahead: u64,
-    pub max_base_layer_blocks_behind: u64,
-    pub num_preshards: NumPreshards,
-    pub pacemaker_max_base_time: Duration,
     pub sidechain_id: Option<RistrettoPublicKey>,
+    pub consensus_constants: ConsensusConstants,
 }

dan_layer/consensus/src/hotstuff/on_propose.rs

@@ -66,7 +66,6 @@ use crate::{
             TransactionLockConflicts,
         },
         HotstuffConfig,
-        EXHAUST_DIVISOR,
     },
     messages::{HotstuffMessage, ProposalMessage},
     tracing::TraceTimer,
@@ -497,7 +496,11 @@ where TConsensusSpec: ConsensusSpec
         );
 
         // batch is empty for is_empty, is_epoch_end and is_epoch_start blocks
-        let mut substate_store = PendingSubstateStore::new(tx, *parent_block.block_id(), self.config.num_preshards);
+        let mut substate_store = PendingSubstateStore::new(
+            tx,
+            *parent_block.block_id(),
+            self.config.consensus_constants.num_preshards,
+        );
         let mut executed_transactions = HashMap::new();
         let timer = TraceTimer::info(LOG_TARGET, "Generating commands").with_iterations(batch.len());
         let mut lock_conflicts = TransactionLockConflicts::new();
@@ -657,7 +660,8 @@ where TConsensusSpec: ConsensusSpec
 
                 if tx_rec.current_decision().is_commit() {
                     let involved = NonZeroU64::new(1).expect("1 > 0");
-                    let leader_fee = tx_rec.calculate_leader_fee(involved, EXHAUST_DIVISOR);
+                    let leader_fee =
+                        tx_rec.calculate_leader_fee(involved, self.config.consensus_constants.fee_exhaust_divisor);
                     tx_rec.set_leader_fee(leader_fee);
                     let diff = execution.result().finalize.result.accept().ok_or_else(|| {
                         HotStuffError::InvariantError(format!(
@@ -863,7 +867,7 @@ where TConsensusSpec: ConsensusSpec
                     tx_rec.transaction_id(),
                 ))
             })?;
-            let leader_fee = tx_rec.calculate_leader_fee(involved, EXHAUST_DIVISOR);
+            let leader_fee = tx_rec.calculate_leader_fee(involved, self.config.consensus_constants.fee_exhaust_divisor);
             tx_rec.set_leader_fee(leader_fee);
         }
         let atom = tx_rec.get_current_transaction_atom();

dan_layer/consensus/src/hotstuff/on_ready_to_vote_on_local_block.rs

@@ -61,7 +61,6 @@ use crate::{
         },
         HotstuffConfig,
         ProposalValidationError,
-        EXHAUST_DIVISOR,
     },
     tracing::TraceTimer,
     traits::{ConsensusSpec, WriteableSubstateStore},
@@ -297,7 +296,8 @@ where TConsensusSpec: ConsensusSpec
     ) -> Result<(), HotStuffError> {
         // Store used for transactions that have inputs without specific versions.
         // It lives through the entire block so multiple transactions can be sequenced together in the same block
-        let mut substate_store = PendingSubstateStore::new(tx, *block.parent(), self.config.num_preshards);
+        let mut substate_store =
+            PendingSubstateStore::new(tx, *block.parent(), self.config.consensus_constants.num_preshards);
         let mut total_leader_fee = 0;
         let locked_block = LockedBlock::get(tx, block.epoch())?;
 
@@ -613,8 +613,10 @@ where TConsensusSpec: ConsensusSpec
                         return Ok(Some(NoVoteReason::NoLeaderFee));
                     }
 
-                    let calculated_leader_fee =
-                        tx_rec.calculate_leader_fee(NonZeroU64::new(1).expect("1 > 0"), EXHAUST_DIVISOR);
+                    let calculated_leader_fee = tx_rec.calculate_leader_fee(
+                        NonZeroU64::new(1).expect("1 > 0"),
+                        self.config.consensus_constants.fee_exhaust_divisor,
+                    );
                     if calculated_leader_fee != *atom.leader_fee.as_ref().expect("None already checked") {
                         warn!(
                             target: LOG_TARGET,
@@ -1226,7 +1228,8 @@ where TConsensusSpec: ConsensusSpec
             let num_involved_shard_groups = tx_rec.evidence().num_shard_groups();
             let involved = NonZeroU64::new(num_involved_shard_groups as u64)
                 .ok_or_else(|| HotStuffError::InvariantError("Number of involved shard groups is 0".to_string()))?;
-            let calculated_leader_fee = tx_rec.calculate_leader_fee(involved, EXHAUST_DIVISOR);
+            let calculated_leader_fee =
+                tx_rec.calculate_leader_fee(involved, self.config.consensus_constants.fee_exhaust_divisor);
             if calculated_leader_fee != *leader_fee {
                 warn!(
                     target: LOG_TARGET,

dan_layer/consensus/src/hotstuff/on_receive_local_proposal.rs

@@ -314,7 +314,9 @@ impl<TConsensusSpec: ConsensusSpec> OnReceiveLocalProposalHandler<TConsensusSpec
             if let Some(vn) = self.epoch_manager.get_our_validator_node(next_epoch).await.optional()? {
                 // TODO: Change VN db to include the shard group in the ValidatorNode struct.
                 let num_committees = self.epoch_manager.get_num_committees(next_epoch).await?;
-                let next_shard_group = vn.shard_key.to_shard_group(self.config.num_preshards, num_committees);
+                let next_shard_group = vn
+                    .shard_key
+                    .to_shard_group(self.config.consensus_constants.num_preshards, num_committees);
                 self.store.with_write_tx(|tx| {
                     // Generate checkpoint
                     create_epoch_checkpoint(tx, epoch, local_committee_info.shard_group())?;
@@ -412,7 +414,7 @@ impl<TConsensusSpec: ConsensusSpec> OnReceiveLocalProposalHandler<TConsensusSpec
             self.leader_strategy.clone(),
             self.outbound_messaging.clone(),
             self.store.clone(),
-            self.config.num_preshards,
+            self.config.consensus_constants.num_preshards,
             local_committee_info,
             blocks,
         ));
@@ -611,7 +613,7 @@ impl<TConsensusSpec: ConsensusSpec> OnReceiveLocalProposalHandler<TConsensusSpec
                 block_description: candidate_block.to_string(),
                 justify_block: candidate_block.justify().as_leaf_block(),
             }
-            .into());
+                .into());
         };
 
         if justify_block.height() != candidate_block.justify().block_height() {
@@ -660,7 +662,7 @@ impl<TConsensusSpec: ConsensusSpec> OnReceiveLocalProposalHandler<TConsensusSpec
                     justify_block_height: justify_block.height(),
                     candidate_block_height: candidate_block.height(),
                 }
-                .into());
+                    .into());
             };
 
             if candidate_block.parent() != last_dummy.id() {