[RFC] Add epoch_start_timestamp_ms to system object (MystenLabs#7518)

This PR exposes timestamp of epoch start to the smart contracts in move, by putting this timestamp in the system object. This can be useful for smart contract that needs some very coarse time before we have more granular timestamps.
sarvex · Jan 24, 2023 · d38bf93 · d38bf93
1 parent 95b7493
commit d38bf93
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Showing 18 changed files with 124 additions and 26 deletions.
diff --git a/crates/sui-adapter/src/execution_engine.rs b/crates/sui-adapter/src/execution_engine.rs
@@ -357,6 +357,7 @@ fn advance_epoch<S: BackingPackageStore + ParentSync + ChildObjectResolver>(
             CallArg::Pure(bcs::to_bytes(&STORAGE_FUND_REINVEST_RATE).unwrap()),
             CallArg::Pure(bcs::to_bytes(&REWARD_SLASHING_RATE).unwrap()),
             CallArg::Pure(bcs::to_bytes(&STAKE_SUBSIDY_RATE).unwrap()),
+            CallArg::Pure(bcs::to_bytes(&change_epoch.epoch_start_timestamp_ms).unwrap()),
         ],
         gas_status.create_move_gas_status(),
         tx_ctx,

diff --git a/crates/sui-config/src/genesis.rs b/crates/sui-config/src/genesis.rs
@@ -695,7 +695,13 @@ fn build_unsigned_genesis_data(
         sui_framework::get_sui_framework(),
     ];
 
-    let objects = create_genesis_objects(&mut genesis_ctx, &modules, objects, validators);
+    let objects = create_genesis_objects(
+        &mut genesis_ctx,
+        &modules,
+        objects,
+        validators,
+        parameters.timestamp_ms,
+    );
 
     let (genesis_transaction, genesis_effects, objects) = create_genesis_transaction(objects);
     let (checkpoint, checkpoint_contents) =
@@ -819,6 +825,7 @@ fn create_genesis_objects(
     modules: &[Vec<CompiledModule>],
     input_objects: &[Object],
     validators: &[GenesisValidatorInfo],
+    epoch_start_timestamp_ms: u64,
 ) -> Vec<Object> {
     let mut store = InMemoryStorage::new(Vec::new());
 
@@ -841,7 +848,14 @@ fn create_genesis_objects(
         store.insert_object(object.to_owned());
     }
 
-    generate_genesis_system_object(&mut store, &move_vm, validators, genesis_ctx).unwrap();
+    generate_genesis_system_object(
+        &mut store,
+        &move_vm,
+        validators,
+        genesis_ctx,
+        epoch_start_timestamp_ms,
+    )
+    .unwrap();
 
     store
         .into_inner()
@@ -924,6 +938,7 @@ pub fn generate_genesis_system_object(
     move_vm: &MoveVM,
     committee: &[GenesisValidatorInfo],
     genesis_ctx: &mut TxContext,
+    epoch_start_timestamp_ms: u64,
 ) -> Result<()> {
     let genesis_digest = genesis_ctx.digest();
     let mut temporary_store =
@@ -989,6 +1004,7 @@ pub fn generate_genesis_system_object(
             CallArg::Pure(bcs::to_bytes(&stakes).unwrap()),
             CallArg::Pure(bcs::to_bytes(&gas_prices).unwrap()),
             CallArg::Pure(bcs::to_bytes(&commission_rates).unwrap()),
+            CallArg::Pure(bcs::to_bytes(&epoch_start_timestamp_ms).unwrap()),
         ],
         SuiGasStatus::new_unmetered().create_move_gas_status(),
         genesis_ctx,

diff --git a/crates/sui-config/tests/snapshot_tests.rs b/crates/sui-config/tests/snapshot_tests.rs
@@ -21,6 +21,7 @@ use insta::assert_yaml_snapshot;
 use multiaddr::Multiaddr;
 use rand::rngs::StdRng;
 use rand::SeedableRng;
+use sui_config::genesis::GenesisChainParameters;
 use sui_config::ValidatorInfo;
 use sui_config::{genesis::Builder, genesis_config::GenesisConfig};
 use sui_types::base_types::{ObjectID, SuiAddress};
@@ -81,6 +82,7 @@ fn populated_genesis_snapshot_matches() {
     let genesis = Builder::new()
         .add_objects(objects)
         .add_validator(validator, pop)
+        .with_parameters(GenesisChainParameters { timestamp_ms: 10 })
         .add_validator_signature(&key)
         .build();
     assert_yaml_snapshot!(genesis.validator_set());

diff --git a/crates/sui-config/tests/snapshots/snapshot_tests__populated_genesis_snapshot_matches-2.snap b/crates/sui-config/tests/snapshots/snapshot_tests__populated_genesis_snapshot_matches-2.snap
@@ -506,4 +506,4 @@ stake_subsidy:
     value: 0
   current_epoch_amount: 1000000
 safe_mode: false
-
+epoch_start_timestamp_ms: 10
diff --git a/crates/sui-core/src/authority.rs b/crates/sui-core/src/authority.rs
@@ -63,7 +63,7 @@ use sui_types::event::{Event, EventID};
 use sui_types::gas::{GasCostSummary, SuiGasStatus};
 use sui_types::messages_checkpoint::{
     CheckpointContents, CheckpointContentsDigest, CheckpointDigest, CheckpointSequenceNumber,
-    CheckpointSummary,
+    CheckpointSummary, CheckpointTimestamp,
 };
 use sui_types::messages_checkpoint::{CheckpointRequest, CheckpointResponse};
 use sui_types::object::{Owner, PastObjectRead};
@@ -2576,6 +2576,7 @@ impl AuthorityState {
         &self,
         epoch_store: &Arc<AuthorityPerEpochStore>,
         gas_cost_summary: &GasCostSummary,
+        epoch_start_timestamp_ms: CheckpointTimestamp,
         timeout: Duration,
         transaction_certifier: &dyn TransactionCertifier,
     ) -> anyhow::Result<VerifiedCertificate> {
@@ -2592,6 +2593,7 @@ impl AuthorityState {
             gas_cost_summary.storage_cost,
             gas_cost_summary.computation_cost,
             gas_cost_summary.storage_rebate,
+            epoch_start_timestamp_ms,
         );
         // If we fail to sign the transaction locally for whatever reason, it's not recoverable.
         self.handle_transaction_impl(tx.clone(), epoch_store)

diff --git a/crates/sui-core/src/checkpoints/mod.rs b/crates/sui-core/src/checkpoints/mod.rs
@@ -562,11 +562,27 @@ impl CheckpointBuilder {
                 "Received {} checkpoint user signatures from consensus",
                 signatures.len()
             );
+            let sequence_number = last_checkpoint
+                .as_ref()
+                .map(|(_, c)| c.sequence_number + 1)
+                .unwrap_or_default();
+            let timestamp_ms = details.timestamp_ms;
+            if let Some((_, last_checkpoint)) = &last_checkpoint {
+                if last_checkpoint.timestamp_ms > timestamp_ms {
+                    error!("Unexpected decrease of checkpoint timestamp, sequence: {}, previous: {}, current: {}",
+                    sequence_number,  last_checkpoint.timestamp_ms, timestamp_ms);
+                }
+            }
+
             let epoch_rolling_gas_cost_summary =
                 self.get_epoch_total_gas_cost(last_checkpoint.as_ref().map(|(_, c)| c), &effects);
             if last_checkpoint_of_epoch {
-                self.augment_epoch_last_checkpoint(&epoch_rolling_gas_cost_summary, &mut effects)
-                    .await?;
+                self.augment_epoch_last_checkpoint(
+                    &epoch_rolling_gas_cost_summary,
+                    timestamp_ms,
+                    &mut effects,
+                )
+                .await?;
             }
 
             let contents =
@@ -583,17 +599,6 @@ impl CheckpointBuilder {
                 .unwrap_or(num_txns);
 
             let previous_digest = last_checkpoint.as_ref().map(|(_, c)| c.digest());
-            let sequence_number = last_checkpoint
-                .as_ref()
-                .map(|(_, c)| c.sequence_number + 1)
-                .unwrap_or_default();
-            let timestamp_ms = details.timestamp_ms;
-            if let Some((_, last_checkpoint)) = &last_checkpoint {
-                if last_checkpoint.timestamp_ms > timestamp_ms {
-                    error!("Unexpected decrease of checkpoint timestamp, sequence: {}, previous: {}, current: {}",
-                    sequence_number,  last_checkpoint.timestamp_ms, timestamp_ms);
-                }
-            }
             let summary = CheckpointSummary::new(
                 epoch,
                 sequence_number,
@@ -655,6 +660,7 @@ impl CheckpointBuilder {
     async fn augment_epoch_last_checkpoint(
         &self,
         epoch_total_gas_cost: &GasCostSummary,
+        epoch_start_timestamp_ms: CheckpointTimestamp,
         effects: &mut Vec<TransactionEffects>,
     ) -> anyhow::Result<()> {
         let timer = Instant::now();
@@ -663,6 +669,7 @@ impl CheckpointBuilder {
             .create_advance_epoch_tx_cert(
                 &self.epoch_store,
                 epoch_total_gas_cost,
+                epoch_start_timestamp_ms,
                 Duration::from_secs(60), // TODO: Is 60s enough?
                 self.transaction_certifier.deref(),
             )

diff --git a/crates/sui-core/tests/staged/sui.yaml b/crates/sui-core/tests/staged/sui.yaml
@@ -41,6 +41,7 @@ ChangeEpoch:
     - storage_charge: U64
     - computation_charge: U64
     - storage_rebate: U64
+    - epoch_start_timestamp_ms: U64
 CircularObjectOwnership:
   STRUCT:
     - object:

diff --git a/crates/sui-framework/docs/genesis.md b/crates/sui-framework/docs/genesis.md
@@ -75,7 +75,7 @@ It will create a singleton SuiSystemState object, which contains
 all the information we need in the system.
 
 
-<pre><code><b>fun</b> <a href="genesis.md#0x2_genesis_create">create</a>(validator_pubkeys: <a href="">vector</a>&lt;<a href="">vector</a>&lt;u8&gt;&gt;, validator_network_pubkeys: <a href="">vector</a>&lt;<a href="">vector</a>&lt;u8&gt;&gt;, validator_worker_pubkeys: <a href="">vector</a>&lt;<a href="">vector</a>&lt;u8&gt;&gt;, validator_proof_of_possessions: <a href="">vector</a>&lt;<a href="">vector</a>&lt;u8&gt;&gt;, validator_sui_addresses: <a href="">vector</a>&lt;<b>address</b>&gt;, validator_names: <a href="">vector</a>&lt;<a href="">vector</a>&lt;u8&gt;&gt;, validator_descriptions: <a href="">vector</a>&lt;<a href="">vector</a>&lt;u8&gt;&gt;, validator_image_urls: <a href="">vector</a>&lt;<a href="">vector</a>&lt;u8&gt;&gt;, validator_project_urls: <a href="">vector</a>&lt;<a href="">vector</a>&lt;u8&gt;&gt;, validator_net_addresses: <a href="">vector</a>&lt;<a href="">vector</a>&lt;u8&gt;&gt;, validator_consensus_addresses: <a href="">vector</a>&lt;<a href="">vector</a>&lt;u8&gt;&gt;, validator_worker_addresses: <a href="">vector</a>&lt;<a href="">vector</a>&lt;u8&gt;&gt;, validator_stakes: <a href="">vector</a>&lt;u64&gt;, validator_gas_prices: <a href="">vector</a>&lt;u64&gt;, validator_commission_rates: <a href="">vector</a>&lt;u64&gt;, ctx: &<b>mut</b> <a href="tx_context.md#0x2_tx_context_TxContext">tx_context::TxContext</a>)
+<pre><code><b>fun</b> <a href="genesis.md#0x2_genesis_create">create</a>(validator_pubkeys: <a href="">vector</a>&lt;<a href="">vector</a>&lt;u8&gt;&gt;, validator_network_pubkeys: <a href="">vector</a>&lt;<a href="">vector</a>&lt;u8&gt;&gt;, validator_worker_pubkeys: <a href="">vector</a>&lt;<a href="">vector</a>&lt;u8&gt;&gt;, validator_proof_of_possessions: <a href="">vector</a>&lt;<a href="">vector</a>&lt;u8&gt;&gt;, validator_sui_addresses: <a href="">vector</a>&lt;<b>address</b>&gt;, validator_names: <a href="">vector</a>&lt;<a href="">vector</a>&lt;u8&gt;&gt;, validator_descriptions: <a href="">vector</a>&lt;<a href="">vector</a>&lt;u8&gt;&gt;, validator_image_urls: <a href="">vector</a>&lt;<a href="">vector</a>&lt;u8&gt;&gt;, validator_project_urls: <a href="">vector</a>&lt;<a href="">vector</a>&lt;u8&gt;&gt;, validator_net_addresses: <a href="">vector</a>&lt;<a href="">vector</a>&lt;u8&gt;&gt;, validator_consensus_addresses: <a href="">vector</a>&lt;<a href="">vector</a>&lt;u8&gt;&gt;, validator_worker_addresses: <a href="">vector</a>&lt;<a href="">vector</a>&lt;u8&gt;&gt;, validator_stakes: <a href="">vector</a>&lt;u64&gt;, validator_gas_prices: <a href="">vector</a>&lt;u64&gt;, validator_commission_rates: <a href="">vector</a>&lt;u64&gt;, epoch_start_timestamp_ms: u64, ctx: &<b>mut</b> <a href="tx_context.md#0x2_tx_context_TxContext">tx_context::TxContext</a>)
 </code></pre>
 
 
@@ -100,6 +100,7 @@ all the information we need in the system.
     validator_stakes: <a href="">vector</a>&lt;u64&gt;,
     validator_gas_prices: <a href="">vector</a>&lt;u64&gt;,
     validator_commission_rates: <a href="">vector</a>&lt;u64&gt;,
+    epoch_start_timestamp_ms: u64,
     ctx: &<b>mut</b> TxContext,
 ) {
     <b>let</b> sui_supply = <a href="sui.md#0x2_sui_new">sui::new</a>(ctx);
@@ -165,6 +166,7 @@ all the information we need in the system.
         <a href="genesis.md#0x2_genesis_INIT_MAX_VALIDATOR_COUNT">INIT_MAX_VALIDATOR_COUNT</a>,
         <a href="genesis.md#0x2_genesis_INIT_MIN_VALIDATOR_STAKE">INIT_MIN_VALIDATOR_STAKE</a>,
         <a href="genesis.md#0x2_genesis_INIT_STAKE_SUBSIDY_AMOUNT">INIT_STAKE_SUBSIDY_AMOUNT</a>,
+        epoch_start_timestamp_ms,
     );
 }
 </code></pre>

diff --git a/crates/sui-framework/docs/sui_system.md b/crates/sui-framework/docs/sui_system.md
@@ -29,6 +29,7 @@
 -  [Function `advance_epoch`](#0x2_sui_system_advance_epoch)
 -  [Function `advance_epoch_safe_mode`](#0x2_sui_system_advance_epoch_safe_mode)
 -  [Function `epoch`](#0x2_sui_system_epoch)
+-  [Function `epoch_start_timestamp_ms`](#0x2_sui_system_epoch_start_timestamp_ms)
 -  [Function `validator_delegate_amount`](#0x2_sui_system_validator_delegate_amount)
 -  [Function `validator_stake_amount`](#0x2_sui_system_validator_stake_amount)
 -  [Function `get_reporters_of`](#0x2_sui_system_get_reporters_of)
@@ -179,6 +180,12 @@ The top-level object containing all information of the Sui system.
  TODO: Down the road we may want to save a few states such as pending gas rewards, so that we could
  redistribute them.
 </dd>
+<dt>
+<code>epoch_start_timestamp_ms: u64</code>
+</dt>
+<dd>
+ Unix timestamp of the current epoch start
+</dd>
 </dl>
 
 
@@ -346,7 +353,7 @@ Create a new SuiSystemState object and make it shared.
 This function will be called only once in genesis.
 
 
-<pre><code><b>public</b>(<b>friend</b>) <b>fun</b> <a href="sui_system.md#0x2_sui_system_create">create</a>(validators: <a href="">vector</a>&lt;<a href="validator.md#0x2_validator_Validator">validator::Validator</a>&gt;, sui_supply: <a href="balance.md#0x2_balance_Supply">balance::Supply</a>&lt;<a href="sui.md#0x2_sui_SUI">sui::SUI</a>&gt;, storage_fund: <a href="balance.md#0x2_balance_Balance">balance::Balance</a>&lt;<a href="sui.md#0x2_sui_SUI">sui::SUI</a>&gt;, max_validator_candidate_count: u64, min_validator_stake: u64, initial_stake_subsidy_amount: u64)
+<pre><code><b>public</b>(<b>friend</b>) <b>fun</b> <a href="sui_system.md#0x2_sui_system_create">create</a>(validators: <a href="">vector</a>&lt;<a href="validator.md#0x2_validator_Validator">validator::Validator</a>&gt;, sui_supply: <a href="balance.md#0x2_balance_Supply">balance::Supply</a>&lt;<a href="sui.md#0x2_sui_SUI">sui::SUI</a>&gt;, storage_fund: <a href="balance.md#0x2_balance_Balance">balance::Balance</a>&lt;<a href="sui.md#0x2_sui_SUI">sui::SUI</a>&gt;, max_validator_candidate_count: u64, min_validator_stake: u64, initial_stake_subsidy_amount: u64, epoch_start_timestamp_ms: u64)
 </code></pre>
 
 
@@ -362,6 +369,7 @@ This function will be called only once in genesis.
     max_validator_candidate_count: u64,
     min_validator_stake: u64,
     initial_stake_subsidy_amount: u64,
+    epoch_start_timestamp_ms: u64,
 ) {
     <b>let</b> validators = <a href="validator_set.md#0x2_validator_set_new">validator_set::new</a>(validators);
     <b>let</b> reference_gas_price = <a href="validator_set.md#0x2_validator_set_derive_reference_gas_price">validator_set::derive_reference_gas_price</a>(&validators);
@@ -380,6 +388,7 @@ This function will be called only once in genesis.
         validator_report_records: <a href="vec_map.md#0x2_vec_map_empty">vec_map::empty</a>(),
         <a href="stake_subsidy.md#0x2_stake_subsidy">stake_subsidy</a>: <a href="stake_subsidy.md#0x2_stake_subsidy_create">stake_subsidy::create</a>(initial_stake_subsidy_amount),
         safe_mode: <b>false</b>,
+        epoch_start_timestamp_ms,
     };
     <a href="transfer.md#0x2_transfer_share_object">transfer::share_object</a>(state);
 }
@@ -1005,7 +1014,7 @@ gas coins.
 4. Update all validators.
 
 
-<pre><code><b>public</b> entry <b>fun</b> <a href="sui_system.md#0x2_sui_system_advance_epoch">advance_epoch</a>(self: &<b>mut</b> <a href="sui_system.md#0x2_sui_system_SuiSystemState">sui_system::SuiSystemState</a>, new_epoch: u64, storage_charge: u64, computation_charge: u64, storage_rebate: u64, storage_fund_reinvest_rate: u64, reward_slashing_rate: u64, stake_subsidy_rate: u64, ctx: &<b>mut</b> <a href="tx_context.md#0x2_tx_context_TxContext">tx_context::TxContext</a>)
+<pre><code><b>public</b> entry <b>fun</b> <a href="sui_system.md#0x2_sui_system_advance_epoch">advance_epoch</a>(self: &<b>mut</b> <a href="sui_system.md#0x2_sui_system_SuiSystemState">sui_system::SuiSystemState</a>, new_epoch: u64, storage_charge: u64, computation_charge: u64, storage_rebate: u64, storage_fund_reinvest_rate: u64, reward_slashing_rate: u64, stake_subsidy_rate: u64, epoch_start_timestamp_ms: u64, ctx: &<b>mut</b> <a href="tx_context.md#0x2_tx_context_TxContext">tx_context::TxContext</a>)
 </code></pre>
 
 
@@ -1024,11 +1033,14 @@ gas coins.
                                      // into storage fund, in basis point.
     reward_slashing_rate: u64, // how much rewards are slashed <b>to</b> punish a <a href="validator.md#0x2_validator">validator</a>, in bps.
     stake_subsidy_rate: u64, // what percentage of the total <a href="stake.md#0x2_stake">stake</a> do we mint <b>as</b> <a href="stake.md#0x2_stake">stake</a> subsidy.
+    epoch_start_timestamp_ms: u64, // Timestamp of the epoch start
     ctx: &<b>mut</b> TxContext,
 ) {
     // Validator will make a special system call <b>with</b> sender set <b>as</b> 0x0.
     <b>assert</b>!(<a href="tx_context.md#0x2_tx_context_sender">tx_context::sender</a>(ctx) == @0x0, 0);
 
+    self.epoch_start_timestamp_ms = epoch_start_timestamp_ms;
+
     <b>let</b> bps_denominator_u64 = (<a href="sui_system.md#0x2_sui_system_BASIS_POINT_DENOMINATOR">BASIS_POINT_DENOMINATOR</a> <b>as</b> u64);
     // Rates can't be higher than 100%.
     <b>assert</b>!(
@@ -1198,6 +1210,31 @@ since epochs are ever-increasing and epoch changes are intended to happen every
 
 
 
+</details>
+
+<a name="0x2_sui_system_epoch_start_timestamp_ms"></a>
+
+## Function `epoch_start_timestamp_ms`
+
+Returns unix timestamp of the start of current epoch
+
+
+<pre><code><b>public</b> <b>fun</b> <a href="sui_system.md#0x2_sui_system_epoch_start_timestamp_ms">epoch_start_timestamp_ms</a>(self: &<a href="sui_system.md#0x2_sui_system_SuiSystemState">sui_system::SuiSystemState</a>): u64
+</code></pre>
+
+
+
+<details>
+<summary>Implementation</summary>
+
+
+<pre><code><b>public</b> <b>fun</b> <a href="sui_system.md#0x2_sui_system_epoch_start_timestamp_ms">epoch_start_timestamp_ms</a>(self: &<a href="sui_system.md#0x2_sui_system_SuiSystemState">SuiSystemState</a>): u64 {
+    self.epoch_start_timestamp_ms
+}
+</code></pre>
+
+
+
 </details>
 
 <a name="0x2_sui_system_validator_delegate_amount"></a>

diff --git a/crates/sui-framework/sources/governance/genesis.move b/crates/sui-framework/sources/governance/genesis.move
@@ -43,6 +43,7 @@ module sui::genesis {
         validator_stakes: vector<u64>,
         validator_gas_prices: vector<u64>,
         validator_commission_rates: vector<u64>,
+        epoch_start_timestamp_ms: u64,
         ctx: &mut TxContext,
     ) {
         let sui_supply = sui::new(ctx);
@@ -108,6 +109,7 @@ module sui::genesis {
             INIT_MAX_VALIDATOR_COUNT,
             INIT_MIN_VALIDATOR_STAKE,
             INIT_STAKE_SUBSIDY_AMOUNT,
+            epoch_start_timestamp_ms,
         );
     }
 
@@ -123,7 +125,8 @@ module sui::genesis {
             storage_fund,
             INIT_MAX_VALIDATOR_COUNT,
             INIT_MIN_VALIDATOR_STAKE,
-            INIT_STAKE_SUBSIDY_AMOUNT
+            INIT_STAKE_SUBSIDY_AMOUNT,
+            0,
         )
     }
 }