feat: add epoch start timestamp (#23)

### Context:
This PR introduces `epoch_start_timestamp` within `ClusterHistoryEntry`
to enhance APY tracking, as detailed in
#18

The `epoch_start_timestamp` is assigned during the execution of the
`copy_cluster_info` ix for the current epoch

### Tests:
A new function has been added to modify the Clock sysvar. This was
necessary because `advance_num_epochs` did not update the Clock sysvar
during tests

### Dependencies
This PR depends on the successful merge of
#22. After merge, I will
update this accordingly.

programs/validator-history/idl/validator_history.json

@@ -649,6 +649,10 @@
             "name": "totalBlocks",
             "type": "u32"
           },
+          {
+            "name": "epochStartTimestamp",
+            "type": "u32"
+          },
           {
             "name": "epoch",
             "type": "u16"
@@ -658,7 +662,7 @@
             "type": {
               "array": [
                 "u8",
-                250
+                246
               ]
             }
           }

programs/validator-history/src/instructions/copy_cluster_info.rs

@@ -1,10 +1,15 @@
-use anchor_lang::{
-    prelude::*,
-    solana_program::{clock::Clock, slot_history::Check},
+use {
+    crate::{
+        errors::ValidatorHistoryError,
+        utils::{cast_epoch, cast_epoch_start_timestamp},
+        ClusterHistory,
+    },
+    anchor_lang::{
+        prelude::*,
+        solana_program::{clock::Clock, slot_history::Check},
+    },
 };
 
-use crate::{errors::ValidatorHistoryError, utils::cast_epoch, ClusterHistory};
-
 #[derive(Accounts)]
 pub struct CopyClusterInfo<'info> {
     #[account(
@@ -29,12 +34,14 @@ pub fn handle_copy_cluster_info(ctx: Context<CopyClusterInfo>) -> Result<()> {
 
     let epoch = cast_epoch(clock.epoch);
 
+    let epoch_start_timestamp = cast_epoch_start_timestamp(clock.epoch_start_timestamp);
     // Sets the slot history for the previous epoch, since the current epoch is not yet complete.
     if epoch > 0 {
         cluster_history_account
             .set_blocks(epoch - 1, blocks_in_epoch(epoch - 1, &slot_history)?)?;
     }
     cluster_history_account.set_blocks(epoch, blocks_in_epoch(epoch, &slot_history)?)?;
+    cluster_history_account.set_epoch_start_timestamp(epoch, epoch_start_timestamp)?;
 
     cluster_history_account.cluster_history_last_update_slot = clock.slot;
 

programs/validator-history/src/state.rs

@@ -1,13 +1,13 @@
-use std::{cmp::Ordering, collections::HashMap, mem::size_of, net::IpAddr};
-
-use anchor_lang::prelude::*;
-use borsh::{BorshDeserialize, BorshSerialize};
-use type_layout::TypeLayout;
-
-use crate::{
-    crds_value::{ContactInfo, LegacyContactInfo, LegacyVersion, Version2},
-    errors::ValidatorHistoryError,
-    utils::cast_epoch,
+use {
+    crate::{
+        crds_value::{ContactInfo, LegacyContactInfo, LegacyVersion, Version2},
+        errors::ValidatorHistoryError,
+        utils::cast_epoch,
+    },
+    anchor_lang::prelude::*,
+    borsh::{BorshDeserialize, BorshSerialize},
+    std::{cmp::Ordering, collections::HashMap, mem::size_of, net::IpAddr},
+    type_layout::TypeLayout,
 };
 
 static_assertions::const_assert_eq!(size_of::<Config>(), 104);
@@ -654,16 +654,18 @@ pub struct ClusterHistory {
 #[zero_copy]
 pub struct ClusterHistoryEntry {
     pub total_blocks: u32,
+    pub epoch_start_timestamp: u32,
     pub epoch: u16,
-    pub padding: [u8; 250],
+    pub padding: [u8; 246],
 }
 
 impl Default for ClusterHistoryEntry {
     fn default() -> Self {
         Self {
             total_blocks: u32::MAX,
             epoch: u16::MAX,
-            padding: [u8::MAX; 250],
+            epoch_start_timestamp: u32::MAX,
+            padding: [u8::MAX; 246],
         }
     }
 }
@@ -793,6 +795,18 @@ impl ClusterHistory {
 
         Ok(())
     }
+    pub fn set_epoch_start_timestamp(
+        &mut self,
+        epoch: u16,
+        epoch_start_timestamp: u32,
+    ) -> Result<()> {
+        if let Some(entry) = self.history.last_mut() {
+            if entry.epoch == epoch {
+                entry.epoch_start_timestamp = epoch_start_timestamp;
+            }
+        }
+        Ok(())
+    }
 }
 
 #[cfg(test)]

programs/validator-history/src/utils.rs

@@ -1,10 +1,16 @@
-use anchor_lang::prelude::{AccountInfo, Pubkey};
-use anchor_lang::solana_program::native_token::lamports_to_sol;
+use anchor_lang::{
+    prelude::{AccountInfo, Pubkey},
+    solana_program::native_token::lamports_to_sol,
+};
 
 pub fn cast_epoch(epoch: u64) -> u16 {
     (epoch % u16::MAX as u64).try_into().unwrap()
 }
 
+pub fn cast_epoch_start_timestamp(start_timestamp: i64) -> u32 {
+    start_timestamp.try_into().unwrap()
+}
+
 pub fn fixed_point_sol(lamports: u64) -> u32 {
     // convert to sol
     let mut sol = lamports_to_sol(lamports);

tests/src/fixtures.rs

@@ -1,24 +1,25 @@
 #![allow(clippy::await_holding_refcell_ref)]
-use anchor_lang::{
-    solana_program::{
-        clock::Clock,
-        pubkey::Pubkey,
-        vote::state::{VoteInit, VoteState, VoteStateVersions},
+use {
+    anchor_lang::{
+        solana_program::{
+            clock::Clock,
+            pubkey::Pubkey,
+            vote::state::{VoteInit, VoteState, VoteStateVersions},
+        },
+        AccountSerialize, InstructionData, ToAccountMetas,
     },
-    AccountSerialize, InstructionData, ToAccountMetas,
-};
-use solana_program_test::*;
-use solana_sdk::{
-    account::Account, epoch_schedule::EpochSchedule, instruction::Instruction, signature::Keypair,
-    signer::Signer, transaction::Transaction,
-};
-use std::{cell::RefCell, rc::Rc};
-
-use jito_tip_distribution::{
-    sdk::derive_tip_distribution_account_address,
-    state::{MerkleRoot, TipDistributionAccount},
+    jito_tip_distribution::{
+        sdk::derive_tip_distribution_account_address,
+        state::{MerkleRoot, TipDistributionAccount},
+    },
+    solana_program_test::*,
+    solana_sdk::{
+        account::Account, epoch_schedule::EpochSchedule, instruction::Instruction,
+        signature::Keypair, signer::Signer, transaction::Transaction,
+    },
+    std::{cell::RefCell, rc::Rc},
+    validator_history::{self, constants::MAX_ALLOC_BYTES, ClusterHistory, ValidatorHistory},
 };
-use validator_history::{self, constants::MAX_ALLOC_BYTES, ClusterHistory, ValidatorHistory};
 
 pub struct TestFixture {
     pub ctx: Rc<RefCell<ProgramTestContext>>,
@@ -248,6 +249,26 @@ impl TestFixture {
             .expect("Failed warping to future epoch");
     }
 
+    pub async fn advance_clock(&self, num_epochs: u64, ms_per_slot: u64) -> u64 {
+        let mut clock: Clock = self
+            .ctx
+            .borrow_mut()
+            .banks_client
+            .get_sysvar()
+            .await
+            .expect("Failed getting clock");
+
+        let epoch_schedule: EpochSchedule = self.ctx.borrow().genesis_config().epoch_schedule;
+        let target_epoch = clock.epoch + num_epochs;
+        let dif_slots = epoch_schedule.get_first_slot_in_epoch(target_epoch) - clock.slot;
+
+        clock.epoch_start_timestamp += (dif_slots * ms_per_slot) as i64;
+        clock.unix_timestamp += (dif_slots * ms_per_slot) as i64;
+        self.ctx.borrow_mut().set_sysvar(&clock);
+
+        dif_slots
+    }
+
     pub async fn submit_transaction_assert_success(&self, transaction: Transaction) {
         let mut ctx = self.ctx.borrow_mut();
         if let Err(e) = ctx

tests/tests/test_cluster_history.rs

@@ -1,15 +1,41 @@
 #![allow(clippy::await_holding_refcell_ref)]
-use anchor_lang::{
-    solana_program::{instruction::Instruction, slot_history::SlotHistory},
-    InstructionData, ToAccountMetas,
+use {
+    anchor_lang::{
+        solana_program::{instruction::Instruction, slot_history::SlotHistory},
+        InstructionData, ToAccountMetas,
+    },
+    solana_program_test::*,
+    solana_sdk::{
+        clock::Clock, compute_budget::ComputeBudgetInstruction, signer::Signer,
+        transaction::Transaction,
+    },
+    tests::fixtures::TestFixture,
+    validator_history::ClusterHistory,
 };
-use solana_program_test::*;
-use solana_sdk::{
-    clock::Clock, compute_budget::ComputeBudgetInstruction, signer::Signer,
-    transaction::Transaction,
-};
-use tests::fixtures::TestFixture;
-use validator_history::ClusterHistory;
+
+const MS_PER_SLOT: u64 = 400;
+
+fn create_copy_cluster_history_transaction(fixture: &TestFixture) -> Transaction {
+    let instruction = Instruction {
+        program_id: validator_history::id(),
+        data: validator_history::instruction::CopyClusterInfo {}.data(),
+        accounts: validator_history::accounts::CopyClusterInfo {
+            cluster_history_account: fixture.cluster_history_account,
+            slot_history: anchor_lang::solana_program::sysvar::slot_history::id(),
+            signer: fixture.keypair.pubkey(),
+        }
+        .to_account_metas(None),
+    };
+    let heap_request_ix = ComputeBudgetInstruction::request_heap_frame(256 * 1024);
+    let compute_budget_ix = ComputeBudgetInstruction::set_compute_unit_limit(300_000);
+
+    Transaction::new_signed_with_payer(
+        &[heap_request_ix, compute_budget_ix, instruction],
+        Some(&fixture.keypair.pubkey()),
+        &[&fixture.keypair],
+        fixture.ctx.borrow().last_blockhash,
+    )
+}
 
 #[tokio::test]
 async fn test_copy_cluster_info() {
@@ -32,25 +58,7 @@ async fn test_copy_cluster_info() {
     slot_history.add(latest_slot + 1);
 
     // Submit instruction
-    let instruction = Instruction {
-        program_id: validator_history::id(),
-        data: validator_history::instruction::CopyClusterInfo {}.data(),
-        accounts: validator_history::accounts::CopyClusterInfo {
-            cluster_history_account: fixture.cluster_history_account,
-            slot_history: anchor_lang::solana_program::sysvar::slot_history::id(),
-            signer: fixture.keypair.pubkey(),
-        }
-        .to_account_metas(None),
-    };
-    let heap_request_ix = ComputeBudgetInstruction::request_heap_frame(256 * 1024);
-    let compute_budget_ix = ComputeBudgetInstruction::set_compute_unit_limit(300_000);
-
-    let transaction = Transaction::new_signed_with_payer(
-        &[heap_request_ix, compute_budget_ix, instruction],
-        Some(&fixture.keypair.pubkey()),
-        &[&fixture.keypair],
-        ctx.borrow().last_blockhash,
-    );
+    let transaction = create_copy_cluster_history_transaction(&fixture);
 
     ctx.borrow_mut().set_sysvar(&slot_history);
     fixture.submit_transaction_assert_success(transaction).await;
@@ -74,3 +82,41 @@ async fn test_copy_cluster_info() {
     assert!(account.history.arr[1].total_blocks == 2);
     assert_eq!(account.cluster_history_last_update_slot, latest_slot)
 }
+
+#[tokio::test]
+async fn test_start_epoch_timestamp() {
+    // Initialize
+    let fixture = TestFixture::new().await;
+    let ctx = &fixture.ctx;
+    fixture.initialize_config().await;
+    fixture.initialize_cluster_history_account().await;
+
+    // Set SlotHistory sysvar
+    let slot_history = SlotHistory::default();
+    ctx.borrow_mut().set_sysvar(&slot_history);
+
+    // Submit epoch 0 instruction
+    let transaction = create_copy_cluster_history_transaction(&fixture);
+    fixture.submit_transaction_assert_success(transaction).await;
+
+    // Change epoch and set clock timestamps in the future
+    fixture.advance_num_epochs(1).await;
+    let dif_slots = fixture.advance_clock(1, MS_PER_SLOT).await;
+
+    // Submit epoch 1 instruction
+    let transaction = create_copy_cluster_history_transaction(&fixture);
+    fixture.submit_transaction_assert_success(transaction).await;
+
+    let account: ClusterHistory = fixture
+        .load_and_deserialize(&fixture.cluster_history_account)
+        .await;
+
+    assert_eq!(account.history.arr[0].epoch, 0);
+    assert_eq!(account.history.arr[1].epoch, 1);
+    assert_ne!(account.history.arr[0].epoch_start_timestamp, u32::MAX);
+    assert_ne!(account.history.arr[1].epoch_start_timestamp, u32::MAX);
+    assert_eq!(
+        account.history.arr[0].epoch_start_timestamp,
+        account.history.arr[1].epoch_start_timestamp - (dif_slots * MS_PER_SLOT) as u32
+    );
+}