From 965204b8e0f48c2d566e9c35b4ca6e7b80a66630 Mon Sep 17 00:00:00 2001
From: Tyera Eulberg <teulberg@gmail.com>
Date: Mon, 11 May 2020 15:47:40 -0600
Subject: [PATCH] Check slot cleaned up for RPC blockstore/slot queries (#9982)

automerge
---
 core/src/lib.rs       |  1 +
 core/src/rpc.rs       | 62 ++++++++++++++++++++++++++++---------------
 core/src/rpc_error.rs | 45 +++++++++++++++++++++++++++++++
 3 files changed, 87 insertions(+), 21 deletions(-)
 create mode 100644 core/src/rpc_error.rs

diff --git a/core/src/lib.rs b/core/src/lib.rs
index 01afae5f1b..1e1114ee3c 100644
--- a/core/src/lib.rs
+++ b/core/src/lib.rs
@@ -40,6 +40,7 @@ mod result;
 pub mod retransmit_stage;
 pub mod rewards_recorder_service;
 pub mod rpc;
+pub mod rpc_error;
 pub mod rpc_pubsub;
 pub mod rpc_pubsub_service;
 pub mod rpc_service;
diff --git a/core/src/rpc.rs b/core/src/rpc.rs
index 32a524c074..7e144fbb99 100644
--- a/core/src/rpc.rs
+++ b/core/src/rpc.rs
@@ -5,11 +5,12 @@ use crate::{
     commitment::{BlockCommitmentArray, BlockCommitmentCache},
     contact_info::ContactInfo,
     non_circulating_supply::calculate_non_circulating_supply,
+    rpc_error::RpcCustomError,
     storage_stage::StorageState,
     validator::ValidatorExit,
 };
 use bincode::serialize;
-use jsonrpc_core::{Error, ErrorCode, Metadata, Result};
+use jsonrpc_core::{Error, Metadata, Result};
 use jsonrpc_derive::rpc;
 use solana_client::{
     rpc_request::{
@@ -18,7 +19,9 @@ use solana_client::{
     rpc_response::*,
 };
 use solana_faucet::faucet::request_airdrop_transaction;
-use solana_ledger::{bank_forks::BankForks, blockstore::Blockstore};
+use solana_ledger::{
+    bank_forks::BankForks, blockstore::Blockstore, blockstore_db::BlockstoreError,
+};
 use solana_perf::packet::PACKET_DATA_SIZE;
 use solana_runtime::{accounts::AccountAddressFilter, bank::Bank};
 use solana_sdk::{
@@ -46,7 +49,6 @@ use std::{
     time::{Duration, Instant},
 };
 
-const JSON_RPC_SERVER_ERROR_0: i64 = -32000;
 const NUM_LARGEST_ACCOUNTS: usize = 20;
 
 type RpcResponse<T> = Result<Response<T>>;
@@ -100,18 +102,13 @@ impl JsonRpcRequestProcessor {
                 .unwrap()
                 .largest_confirmed_root();
             debug!("RPC using block: {:?}", cluster_root);
-            r_bank_forks
-                .get(cluster_root)
-                .cloned()
-                .ok_or_else(|| Error {
-                    code: ErrorCode::ServerError(JSON_RPC_SERVER_ERROR_0),
-                    message: format!(
-                        "Cluster largest_confirmed_root {} does not exist on node. Node root: {}",
-                        cluster_root,
-                        r_bank_forks.root(),
-                    ),
-                    data: None,
-                })
+            r_bank_forks.get(cluster_root).cloned().ok_or_else(|| {
+                RpcCustomError::NonexistentClusterRoot {
+                    cluster_root,
+                    node_root: r_bank_forks.root(),
+                }
+                .into()
+            })
         }
     }
 
@@ -421,6 +418,29 @@ impl JsonRpcRequestProcessor {
         }
     }
 
+    fn check_slot_cleaned_up<T>(
+        &self,
+        result: &std::result::Result<T, BlockstoreError>,
+        slot: Slot,
+    ) -> Result<()>
+    where
+        T: std::fmt::Debug,
+    {
+        if result.is_err() {
+            if let BlockstoreError::SlotCleanedUp = result.as_ref().unwrap_err() {
+                return Err(RpcCustomError::BlockCleanedUp {
+                    slot,
+                    first_available_block: self
+                        .blockstore
+                        .get_first_available_block()
+                        .unwrap_or_default(),
+                }
+                .into());
+            }
+        }
+        Ok(())
+    }
+
     pub fn get_confirmed_block(
         &self,
         slot: Slot,
@@ -434,7 +454,9 @@ impl JsonRpcRequestProcessor {
                     .unwrap()
                     .largest_confirmed_root()
         {
-            Ok(self.blockstore.get_confirmed_block(slot, encoding).ok())
+            let result = self.blockstore.get_confirmed_block(slot, encoding);
+            self.check_slot_cleaned_up(&result, slot)?;
+            Ok(result.ok())
         } else {
             Ok(None)
         }
@@ -482,11 +504,9 @@ impl JsonRpcRequestProcessor {
             let stakes = HashMap::new();
             let stakes = bank.epoch_vote_accounts(epoch).unwrap_or(&stakes);
 
-            Ok(self
-                .blockstore
-                .get_block_time(slot, slot_duration, stakes)
-                .ok()
-                .unwrap_or(None))
+            let result = self.blockstore.get_block_time(slot, slot_duration, stakes);
+            self.check_slot_cleaned_up(&result, slot)?;
+            Ok(result.ok().unwrap_or(None))
         } else {
             Ok(None)
         }
diff --git a/core/src/rpc_error.rs b/core/src/rpc_error.rs
new file mode 100644
index 0000000000..ab727776ef
--- /dev/null
+++ b/core/src/rpc_error.rs
@@ -0,0 +1,45 @@
+use jsonrpc_core::{Error, ErrorCode};
+use solana_sdk::clock::Slot;
+
+const JSON_RPC_SERVER_ERROR_0: i64 = -32000;
+const JSON_RPC_SERVER_ERROR_1: i64 = -32001;
+
+pub enum RpcCustomError {
+    NonexistentClusterRoot {
+        cluster_root: Slot,
+        node_root: Slot,
+    },
+    BlockCleanedUp {
+        slot: Slot,
+        first_available_block: Slot,
+    },
+}
+
+impl From<RpcCustomError> for Error {
+    fn from(e: RpcCustomError) -> Self {
+        match e {
+            RpcCustomError::NonexistentClusterRoot {
+                cluster_root,
+                node_root,
+            } => Self {
+                code: ErrorCode::ServerError(JSON_RPC_SERVER_ERROR_0),
+                message: format!(
+                    "Cluster largest_confirmed_root {} does not exist on node. Node root: {}",
+                    cluster_root, node_root,
+                ),
+                data: None,
+            },
+            RpcCustomError::BlockCleanedUp {
+                slot,
+                first_available_block,
+            } => Self {
+                code: ErrorCode::ServerError(JSON_RPC_SERVER_ERROR_1),
+                message: format!(
+                    "Block {} cleaned up, does not exist on node. First available block: {}",
+                    slot, first_available_block,
+                ),
+                data: None,
+            },
+        }
+    }
+}