Add Incremental Snapshot support to RPC

client/src/mock_sender.rs

@@ -8,8 +8,9 @@ use {
         rpc_response::{
             Response, RpcAccountBalance, RpcBlockProduction, RpcBlockProductionRange, RpcBlockhash,
             RpcConfirmedTransactionStatusWithSignature, RpcContactInfo, RpcFees, RpcPerfSample,
-            RpcResponseContext, RpcSimulateTransactionResult, RpcStakeActivation, RpcSupply,
-            RpcVersionInfo, RpcVoteAccountInfo, RpcVoteAccountStatus, StakeActivationState,
+            RpcResponseContext, RpcSimulateTransactionResult, RpcSnapshotSlotInfo,
+            RpcStakeActivation, RpcSupply, RpcVersionInfo, RpcVoteAccountInfo,
+            RpcVoteAccountStatus, StakeActivationState,
         },
         rpc_sender::RpcSender,
     },
@@ -222,6 +223,10 @@ impl RpcSender for MockSender {
             "getMaxShredInsertSlot" => json![0],
             "requestAirdrop" => Value::String(Signature::new(&[8; 64]).to_string()),
             "getSnapshotSlot" => Value::Number(Number::from(0)),
+            "getHighestSnapshotSlot" => json!(RpcSnapshotSlotInfo {
+                full: 100,
+                incremental: Some(110),
+            }),
             "getBlockHeight" => Value::Number(Number::from(1234)),
             "getSlotLeaders" => json!([PUBKEY]),
             "getBlockProduction" => {

client/src/rpc_client.rs

@@ -1018,13 +1018,16 @@ impl RpcClient {
         )
     }
 
-    /// Returns the highest slot that the node has a snapshot for.
+    /// Returns the highest slot information that the node has snapshots for.
+    ///
+    /// This will find the highest full snapshot slot, and the highest incremental snapshot slot
+    /// _based on_ the full snapshot slot, if there is one.
     ///
     /// # RPC Reference
     ///
-    /// This method corresponds directly to the [`getSnapshotSlot`] RPC method.
+    /// This method corresponds directly to the [`getHighestSnapshotSlot`] RPC method.
     ///
-    /// [`getSnapshotSlot`]: https://docs.solana.com/developing/clients/jsonrpc-api#getsnapshotslot
+    /// [`getHighestSnapshotSlot`]: https://docs.solana.com/developing/clients/jsonrpc-api#gethighestsnapshotslot
     ///
     /// # Examples
     ///
@@ -1034,9 +1037,18 @@ impl RpcClient {
     /// #     client_error::ClientError,
     /// # };
     /// # let rpc_client = RpcClient::new_mock("succeeds".to_string());
-    /// let slot = rpc_client.get_snapshot_slot()?;
+    /// let snapshot_slot_info = rpc_client.get_highest_snapshot_slot()?;
     /// # Ok::<(), ClientError>(())
     /// ```
+    pub fn get_highest_snapshot_slot(&self) -> ClientResult<RpcSnapshotSlotInfo> {
+        self.send(RpcRequest::GetHighestSnapshotSlot, Value::Null)
+    }
+
+    #[deprecated(
+        since = "1.8.0",
+        note = "Please use RpcClient::get_highest_snapshot_slot() instead"
+    )]
+    #[allow(deprecated)]
     pub fn get_snapshot_slot(&self) -> ClientResult<Slot> {
         self.send(RpcRequest::GetSnapshotSlot, Value::Null)
     }

client/src/rpc_request.rs

@@ -79,6 +79,11 @@ pub enum RpcRequest {
     )]
     GetRecentBlockhash,
     GetRecentPerformanceSamples,
+    GetHighestSnapshotSlot,
+    #[deprecated(
+        since = "1.8.0",
+        note = "Please use RpcRequest::GetHighestSnapshotSlot instead"
+    )]
     GetSnapshotSlot,
     GetSignaturesForAddress,
     GetSignatureStatuses,
@@ -151,6 +156,7 @@ impl fmt::Display for RpcRequest {
             RpcRequest::GetProgramAccounts => "getProgramAccounts",
             RpcRequest::GetRecentBlockhash => "getRecentBlockhash",
             RpcRequest::GetRecentPerformanceSamples => "getRecentPerformanceSamples",
+            RpcRequest::GetHighestSnapshotSlot => "getHighestSnapshotSlot",
             RpcRequest::GetSnapshotSlot => "getSnapshotSlot",
             RpcRequest::GetSignaturesForAddress => "getSignaturesForAddress",
             RpcRequest::GetSignatureStatuses => "getSignatureStatuses",

client/src/rpc_response.rs

@@ -435,3 +435,9 @@ impl From<ConfirmedTransactionStatusWithSignature> for RpcConfirmedTransactionSt
         }
     }
 }
+
+#[derive(Serialize, Deserialize, Clone, Copy, Debug, PartialEq)]
+pub struct RpcSnapshotSlotInfo {
+    pub full: Slot,
+    pub incremental: Option<Slot>,
+}

docs/src/developing/clients/jsonrpc-api.md

@@ -34,6 +34,7 @@ gives a convenient interface for the RPC methods.
 - [getFirstAvailableBlock](jsonrpc-api.md#getfirstavailableblock)
 - [getGenesisHash](jsonrpc-api.md#getgenesishash)
 - [getHealth](jsonrpc-api.md#gethealth)
+- [getHighestSnapshotSlot](jsonrpc-api.md#gethighestsnapshotslot)
 - [getIdentity](jsonrpc-api.md#getidentity)
 - [getInflationGovernor](jsonrpc-api.md#getinflationgovernor)
 - [getInflationRate](jsonrpc-api.md#getinflationrate)
@@ -53,7 +54,6 @@ gives a convenient interface for the RPC methods.
 - [getSlotLeader](jsonrpc-api.md#getslotleader)
 - [getSlotLeaders](jsonrpc-api.md#getslotleaders)
 - [getStakeActivation](jsonrpc-api.md#getstakeactivation)
-- [getSnapshotSlot](jsonrpc-api.md#getsnapshotslot)
 - [getSupply](jsonrpc-api.md#getsupply)
 - [getTokenAccountBalance](jsonrpc-api.md#gettokenaccountbalance)
 - [getTokenAccountsByDelegate](jsonrpc-api.md#gettokenaccountsbydelegate)
@@ -101,6 +101,7 @@ Unstable methods may see breaking changes in patch releases and may not be suppo
 - [getFeeRateGovernor](jsonrpc-api.md#getfeerategovernor)
 - [getFees](jsonrpc-api.md#getfees)
 - [getRecentBlockhash](jsonrpc-api.md#getrecentblockhash)
+- [getSnapshotSlot](jsonrpc-api.md#getsnapshotslot)
 
 ## Request Formatting
 
@@ -1296,6 +1297,46 @@ Unhealthy Result (if additional information is available)
 }
 ```
 
+### getHighestSnapshotSlot
+
+**NEW: This method is only available in solana-core v1.8 or newer. Please use
+[getSnapshotSlot](jsonrpc-api.md#getsnapshotslot) for solana-core v1.7**
+
+Returns the highest slot information that the node has snapshots for.
+
+This will find the highest full snapshot slot, and the highest incremental
+snapshot slot _based on_ the full snapshot slot, if there is one.
+
+#### Parameters:
+
+None
+
+#### Results:
+
+- `<object>`
+  - `full: <u64>` - Highest full snapshot slot
+  - `incremental: <u64 | undefined>` - Highest incremental snapshot slot _based on_ `full`
+
+
+#### Example:
+
+Request:
+```bash
+curl http://localhost:8899 -X POST -H "Content-Type: application/json" -d '
+  {"jsonrpc":"2.0","id":1,"method":"getHighestSnapshotSlot"}
+'
+```
+
+Result:
+```json
+{"jsonrpc":"2.0","result":{"full":100,"incremental":110},"id":1}
+```
+
+Result when the node has no snapshot:
+```json
+{"jsonrpc":"2.0","error":{"code":-32008,"message":"No snapshot"},"id":1}
+```
+
 ### getIdentity
 
 Returns the identity pubkey for the current node
@@ -2121,38 +2162,6 @@ Result:
 }
 ```
 
-
-### getSnapshotSlot
-
-Returns the highest slot that the node has a snapshot for
-
-#### Parameters:
-
-None
-
-#### Results:
-
-- `<u64>` - Snapshot slot
-
-#### Example:
-
-Request:
-```bash
-curl http://localhost:8899 -X POST -H "Content-Type: application/json" -d '
-  {"jsonrpc":"2.0","id":1, "method":"getSnapshotSlot"}
-'
-```
-
-Result:
-```json
-{"jsonrpc":"2.0","result":100,"id":1}
-```
-
-Result when the node has no snapshot:
-```json
-{"jsonrpc":"2.0","error":{"code":-32008,"message":"No snapshot"},"id":1}
-```
-
 ### getSignaturesForAddress
 
 **NEW: This method is only available in solana-core v1.7 or newer. Please use
@@ -4778,3 +4787,37 @@ Result:
   "id": 1
 }
 ```
+
+### getSnapshotSlot
+
+**DEPRECATED: Please use [getHighestSnapshotSlot](jsonrpc-api.md#gethighestsnapshotslot) instead**
+This method is expected to be removed in solana-core v1.9
+
+Returns the highest slot that the node has a snapshot for
+
+#### Parameters:
+
+None
+
+#### Results:
+
+- `<u64>` - Snapshot slot
+
+#### Example:
+
+Request:
+```bash
+curl http://localhost:8899 -X POST -H "Content-Type: application/json" -d '
+  {"jsonrpc":"2.0","id":1, "method":"getSnapshotSlot"}
+'
+```
+
+Result:
+```json
+{"jsonrpc":"2.0","result":100,"id":1}
+```
+
+Result when the node has no snapshot:
+```json
+{"jsonrpc":"2.0","error":{"code":-32008,"message":"No snapshot"},"id":1}
+```

rpc/src/rpc.rs

@@ -2276,8 +2276,8 @@ pub mod rpc_minimal {
             commitment: Option<CommitmentConfig>,
         ) -> Result<u64>;
 
-        #[rpc(meta, name = "getSnapshotSlot")]
-        fn get_snapshot_slot(&self, meta: Self::Metadata) -> Result<Slot>;
+        #[rpc(meta, name = "getHighestSnapshotSlot")]
+        fn get_highest_snapshot_slot(&self, meta: Self::Metadata) -> Result<RpcSnapshotSlotInfo>;
 
         #[rpc(meta, name = "getTransactionCount")]
         fn get_transaction_count(
@@ -2373,16 +2373,31 @@ pub mod rpc_minimal {
             Ok(meta.get_block_height(commitment))
         }
 
-        fn get_snapshot_slot(&self, meta: Self::Metadata) -> Result<Slot> {
-            debug!("get_snapshot_slot rpc request received");
+        fn get_highest_snapshot_slot(&self, meta: Self::Metadata) -> Result<RpcSnapshotSlotInfo> {
+            debug!("get_highest_snapshot_slot rpc request received");
 
-            meta.snapshot_config
-                .and_then(|snapshot_config| {
-                    snapshot_utils::get_highest_full_snapshot_archive_slot(
-                        &snapshot_config.snapshot_archives_dir,
-                    )
-                })
-                .ok_or_else(|| RpcCustomError::NoSnapshot.into())
+            if meta.snapshot_config.is_none() {
+                return Err(RpcCustomError::NoSnapshot.into());
+            }
+
+            let snapshot_archives_dir = meta
+                .snapshot_config
+                .map(|snapshot_config| snapshot_config.snapshot_archives_dir)
+                .unwrap();
+
+            let full_snapshot_slot =
+                snapshot_utils::get_highest_full_snapshot_archive_slot(&snapshot_archives_dir)
+                    .ok_or(RpcCustomError::NoSnapshot)?;
+            let incremental_snapshot_slot =
+                snapshot_utils::get_highest_incremental_snapshot_archive_slot(
+                    &snapshot_archives_dir,
+                    full_snapshot_slot,
+                );
+
+            Ok(RpcSnapshotSlotInfo {
+                full: full_snapshot_slot,
+                incremental: incremental_snapshot_slot,
+            })
         }
 
         fn get_transaction_count(
@@ -3686,6 +3701,9 @@ pub mod rpc_deprecated_v1_8 {
             &self,
             meta: Self::Metadata,
         ) -> Result<RpcResponse<RpcFeeRateGovernor>>;
+
+        #[rpc(meta, name = "getSnapshotSlot")]
+        fn get_snapshot_slot(&self, meta: Self::Metadata) -> Result<Slot>;
     }
 
     pub struct DeprecatedV1_8Impl;
@@ -3729,6 +3747,18 @@ pub mod rpc_deprecated_v1_8 {
             debug!("get_fee_rate_governor rpc request received");
             Ok(meta.get_fee_rate_governor())
         }
+
+        fn get_snapshot_slot(&self, meta: Self::Metadata) -> Result<Slot> {
+            debug!("get_snapshot_slot rpc request received");
+
+            meta.snapshot_config
+                .and_then(|snapshot_config| {
+                    snapshot_utils::get_highest_full_snapshot_archive_slot(
+                        &snapshot_config.snapshot_archives_dir,
+                    )
+                })
+                .ok_or_else(|| RpcCustomError::NoSnapshot.into())
+        }
     }
 }