Rpc: introduce get_inflation_reward rpc call (#16278)

* feat: introduce get_inflation_reward rpc call

* fix: style suggestions

* fix: more style changes and match how other rpc functions are defined

* feat: get reward for a single epoch

* feat: default to the most recent epoch

* fix: don't factor out get_confirmed_block

* style: introduce from impl for RpcEncodingConfigWrapper

* style: bring commitment into variable

* feat: support multiple pubkeys for get_inflation_reward

* feat: add get_inflation_reward to rpc client

* feat: return rewards in order

* fix: rename pubkeys to addresses

* docs: introduce jsonrpc docs for get_inflation_reward

* style: early return in map (not sure which is more idiomatic)

* fix: call the rpc client function args addresses as well

* fix: style

* fix: filter out only addresses we care about

* style: make this more idiomatic

* fix: change rpc client epoch to optional and include some docs edits

* feat: filter out rent rewards in get_inflation_reward

* feat: add option epoch config param to get_inflation_reward

* feat: rpc client get_inflation_reward takes epoch instead of config and some filter staking and voting rewards

client/src/rpc_client.rs

@@ -5,10 +5,10 @@ use {
         mock_sender::{MockSender, Mocks},
         rpc_config::RpcAccountInfoConfig,
         rpc_config::{
-            RpcConfirmedBlockConfig, RpcConfirmedTransactionConfig,
+            RpcConfirmedBlockConfig, RpcConfirmedTransactionConfig, RpcEpochConfig,
             RpcGetConfirmedSignaturesForAddress2Config, RpcLargestAccountsConfig,
             RpcProgramAccountsConfig, RpcSendTransactionConfig, RpcSimulateTransactionConfig,
-            RpcStakeConfig, RpcTokenAccountsFilter,
+            RpcTokenAccountsFilter,
         },
         rpc_request::{RpcError, RpcRequest, RpcResponseErrorData, TokenAccountsFilter},
         rpc_response::*,
@@ -436,7 +436,7 @@ impl RpcClient {
             RpcRequest::GetStakeActivation,
             json!([
                 stake_account.to_string(),
-                RpcStakeConfig {
+                RpcEpochConfig {
                     epoch,
                     commitment: Some(self.commitment_config),
                 }
@@ -764,6 +764,27 @@ impl RpcClient {
         self.send(RpcRequest::GetInflationRate, Value::Null)
     }
 
+    pub fn get_inflation_reward(
+        &self,
+        addresses: &[Pubkey],
+        epoch: Option<Epoch>,
+    ) -> ClientResult<Vec<Option<RpcInflationReward>>> {
+        let addresses: Vec<_> = addresses
+            .iter()
+            .map(|address| address.to_string())
+            .collect();
+        self.send(
+            RpcRequest::GetInflationReward,
+            json!([
+                addresses,
+                RpcEpochConfig {
+                    epoch,
+                    commitment: Some(self.commitment_config),
+                }
+            ]),
+        )
+    }
+
     pub fn get_version(&self) -> ClientResult<RpcVersionInfo> {
         self.send(RpcRequest::GetVersion, Value::Null)
     }

client/src/rpc_config.rs

@@ -50,7 +50,7 @@ pub struct RpcLargestAccountsConfig {
 
 #[derive(Debug, Clone, Default, PartialEq, Serialize, Deserialize)]
 #[serde(rename_all = "camelCase")]
-pub struct RpcStakeConfig {
+pub struct RpcEpochConfig {
     pub epoch: Option<Epoch>,
     #[serde(flatten)]
     pub commitment: Option<CommitmentConfig>,
@@ -161,6 +161,12 @@ impl RpcConfirmedBlockConfig {
     }
 }
 
+impl From<RpcConfirmedBlockConfig> for RpcEncodingConfigWrapper<RpcConfirmedBlockConfig> {
+    fn from(config: RpcConfirmedBlockConfig) -> Self {
+        RpcEncodingConfigWrapper::Current(Some(config))
+    }
+}
+
 #[derive(Debug, Clone, Copy, Default, PartialEq, Serialize, Deserialize)]
 #[serde(rename_all = "camelCase")]
 pub struct RpcConfirmedTransactionConfig {

client/src/rpc_request.rs

@@ -30,6 +30,7 @@ pub enum RpcRequest {
     GetIdentity,
     GetInflationGovernor,
     GetInflationRate,
+    GetInflationReward,
     GetLargestAccounts,
     GetLeaderSchedule,
     GetMaxRetransmitSlot,
@@ -91,6 +92,7 @@ impl fmt::Display for RpcRequest {
             RpcRequest::GetIdentity => "getIdentity",
             RpcRequest::GetInflationGovernor => "getInflationGovernor",
             RpcRequest::GetInflationRate => "getInflationRate",
+            RpcRequest::GetInflationReward => "getInflationReward",
             RpcRequest::GetLargestAccounts => "getLargestAccounts",
             RpcRequest::GetLeaderSchedule => "getLeaderSchedule",
             RpcRequest::GetMaxRetransmitSlot => "getMaxRetransmitSlot",

client/src/rpc_response.rs

@@ -362,6 +362,15 @@ pub struct RpcPerfSample {
     pub sample_period_secs: u16,
 }
 
+#[derive(Clone, Debug, PartialEq, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct RpcInflationReward {
+    pub epoch: Epoch,
+    pub effective_slot: Slot,
+    pub amount: u64,       // lamports
+    pub post_balance: u64, // lamports
+}
+
 impl From<ConfirmedTransactionStatusWithSignature> for RpcConfirmedTransactionStatusWithSignature {
     fn from(value: ConfirmedTransactionStatusWithSignature) -> Self {
         let ConfirmedTransactionStatusWithSignature {

core/src/rpc.rs

@@ -70,8 +70,8 @@ use solana_sdk::{
 };
 use solana_stake_program::stake_state::StakeState;
 use solana_transaction_status::{
-    EncodedConfirmedTransaction, TransactionConfirmationStatus, TransactionStatus,
+    EncodedConfirmedTransaction, Reward, RewardType, TransactionConfirmationStatus,
-    UiConfirmedBlock, UiTransactionEncoding,
+    TransactionStatus, UiConfirmedBlock, UiTransactionEncoding,
 };
 use solana_vote_program::vote_state::{VoteState, MAX_LOCKOUT_HISTORY};
 use spl_token_v2_0::{
@@ -382,6 +382,92 @@ impl JsonRpcRequestProcessor {
         Ok(result)
     }
 
+    pub fn get_inflation_reward(
+        &self,
+        addresses: Vec<Pubkey>,
+        config: Option<RpcEpochConfig>,
+    ) -> Result<Vec<Option<RpcInflationReward>>> {
+        let config = config.unwrap_or_default();
+        let epoch_schedule = self.get_epoch_schedule();
+        let first_available_block = self.get_first_available_block();
+        let epoch = config.epoch.unwrap_or_else(|| {
+            epoch_schedule
+                .get_epoch(self.get_slot(config.commitment))
+                .saturating_sub(1)
+        });
+
+        // Rewards for this epoch are found in the first confirmed block of the next epoch
+        let first_slot_in_epoch = epoch_schedule.get_first_slot_in_epoch(epoch.saturating_add(1));
+        if first_slot_in_epoch < first_available_block {
+            if self.bigtable_ledger_storage.is_some() {
+                return Err(RpcCustomError::LongTermStorageSlotSkipped {
+                    slot: first_slot_in_epoch,
+                }
+                .into());
+            } else {
+                return Err(RpcCustomError::BlockCleanedUp {
+                    slot: first_slot_in_epoch,
+                    first_available_block,
+                }
+                .into());
+            }
+        }
+
+        let first_confirmed_block_in_epoch = *self
+            .get_confirmed_blocks_with_limit(first_slot_in_epoch, 1, config.commitment)?
+            .get(0)
+            .ok_or(RpcCustomError::BlockNotAvailable {
+                slot: first_slot_in_epoch,
+            })?;
+
+        let first_confirmed_block = if let Ok(Some(first_confirmed_block)) = self
+            .get_confirmed_block(
+                first_confirmed_block_in_epoch,
+                Some(RpcConfirmedBlockConfig::rewards_only().into()),
+            ) {
+            first_confirmed_block
+        } else {
+            return Err(RpcCustomError::BlockNotAvailable {
+                slot: first_confirmed_block_in_epoch,
+            }
+            .into());
+        };
+
+        let addresses: Vec<String> = addresses
+            .into_iter()
+            .map(|pubkey| pubkey.to_string())
+            .collect();
+
+        let reward_hash: HashMap<String, Reward> = first_confirmed_block
+            .rewards
+            .unwrap_or_default()
+            .into_iter()
+            .filter_map(|reward| match reward.reward_type? {
+                RewardType::Staking | RewardType::Voting => addresses
+                    .contains(&reward.pubkey)
+                    .then(|| (reward.clone().pubkey, reward)),
+                _ => None,
+            })
+            .collect();
+
+        let rewards = addresses
+            .iter()
+            .map(|address| {
+                if let Some(reward) = reward_hash.get(address) {
+                    return Some(RpcInflationReward {
+                        epoch,
+                        effective_slot: first_confirmed_block_in_epoch,
+                        amount: reward.lamports.abs() as u64,
+                        post_balance: reward.post_balance,
+                    });
+                }
+                None
+            })
+            .collect();
+
+        Ok(rewards)
+    }
+
     pub fn get_inflation_governor(
         &self,
         commitment: Option<CommitmentConfig>,
@@ -1258,7 +1344,7 @@ impl JsonRpcRequestProcessor {
     pub fn get_stake_activation(
         &self,
         pubkey: &Pubkey,
-        config: Option<RpcStakeConfig>,
+        config: Option<RpcEpochConfig>,
     ) -> Result<RpcStakeActivation> {
         let config = config.unwrap_or_default();
         let bank = self.bank(config.commitment);
@@ -2184,6 +2270,14 @@ pub mod rpc_full {
             commitment: Option<CommitmentConfig>,
         ) -> Result<u64>;
 
+        #[rpc(meta, name = "getInflationReward")]
+        fn get_inflation_reward(
+            &self,
+            meta: Self::Metadata,
+            address_strs: Vec<String>,
+            config: Option<RpcEpochConfig>,
+        ) -> Result<Vec<Option<RpcInflationReward>>>;
+
         #[rpc(meta, name = "getInflationGovernor")]
         fn get_inflation_governor(
             &self,
@@ -2388,7 +2482,7 @@ pub mod rpc_full {
             &self,
             meta: Self::Metadata,
             pubkey_str: String,
-            config: Option<RpcStakeConfig>,
+            config: Option<RpcEpochConfig>,
         ) -> Result<RpcStakeActivation>;
 
         // SPL Token-specific RPC endpoints
@@ -3127,7 +3221,7 @@ pub mod rpc_full {
             &self,
             meta: Self::Metadata,
             pubkey_str: String,
-            config: Option<RpcStakeConfig>,
+            config: Option<RpcEpochConfig>,
         ) -> Result<RpcStakeActivation> {
             debug!(
                 "get_stake_activation rpc request received: {:?}",
@@ -3137,6 +3231,25 @@ pub mod rpc_full {
             meta.get_stake_activation(&pubkey, config)
         }
 
+        fn get_inflation_reward(
+            &self,
+            meta: Self::Metadata,
+            address_strs: Vec<String>,
+            config: Option<RpcEpochConfig>,
+        ) -> Result<Vec<Option<RpcInflationReward>>> {
+            debug!(
+                "get_inflation_reward rpc request received: {:?}",
+                address_strs.len()
+            );
+
+            let mut addresses: Vec<Pubkey> = vec![];
+            for address_str in address_strs {
+                addresses.push(verify_pubkey(address_str)?);
+            }
+
+            meta.get_inflation_reward(addresses, config)
+        }
+
         fn get_token_account_balance(
             &self,
             meta: Self::Metadata,

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

@@ -40,6 +40,7 @@ gives a convenient interface for the RPC methods.
 - [getIdentity](jsonrpc-api.md#getidentity)
 - [getInflationGovernor](jsonrpc-api.md#getinflationgovernor)
 - [getInflationRate](jsonrpc-api.md#getinflationrate)
+- [getInflationReward](jsonrpc-api.md#getinflationreward)
 - [getLargestAccounts](jsonrpc-api.md#getlargestaccounts)
 - [getLeaderSchedule](jsonrpc-api.md#getleaderschedule)
 - [getMaxRetransmitSlot](jsonrpc-api.md#getmaxretransmitslot)
@@ -1468,6 +1469,58 @@ Result:
 {"jsonrpc":"2.0","result":{"epoch":100,"foundation":0.001,"total":0.149,"validator":0.148},"id":1}
 ```
 
+### getInflationReward
+
+Returns the inflation reward for a list of addresses for an epoch
+
+#### Parameters:
+- `<array>` - An array of addresses to query, as base-58 encoded strings
+* `<object>` - (optional) Configuration object containing the following optional fields:
+  * (optional) [Commitment](jsonrpc-api.md#configuring-state-commitment)
+  * (optional) `epoch: <u64>` - An epoch for which the reward occurs. If omitted, the previous epoch will be used
+
+#### Results
+
+The result field will be a JSON array with the following fields:
+
+- `epoch: <u64>`, epoch
+- `effective_slot: <u64>`, the slot in which the rewards are effective
+- `amount: <u64>`, reward amount in lamports
+- `post_balance: <u64>`, post balance of the account in lamports
+
+#### Example
+
+Request:
+```bash
+curl http://localhost:8899 -X POST -H "Content-Type: application/json" -d '
+  {
+    "jsonrpc": "2.0",
+    "id": 1,
+    "method": "getInflationReward",
+    "params": [
+       ["6dmNQ5jwLeLk5REvio1JcMshcbvkYMwy26sJ8pbkvStu", "BGsqMegLpV6n6Ve146sSX2dTjUMj3M92HnU8BbNRMhF2"], 2
+    ]
+  }
+'
+```
+
+Response:
+```json
+  {
+    "jsonrpc": "2.0",
+    "result": [
+        {
+            "amount": 2500,
+            "effectiveSlot": 224,
+            "epoch": 2,
+            "postBalance": 499999442500
+        },
+        null
+    ],
+    "id": 1
+  }
+```
+
 ### getLargestAccounts
 
 Returns the 20 largest accounts, by lamport balance (results may be cached up to two hours)