Merge bitcoin/bitcoin#31196: Prune mining interface

c991cea1a0 Remove processNewBlock() from mining interface (Sjors Provoost)
9a47852d88 Remove getTransactionsUpdated() from mining interface (Sjors Provoost)
bfc4e029d4 Remove testBlockValidity() from mining interface (Sjors Provoost)

Pull request description:

  There are three methods in the mining interface that can be dropped. The Template Provider doesn't need them and other application should probably not use them either.

  1. `processNewBlock()` was added in 7b4d3249ce, but became unnecessary with the introduction of interfaces::BlockTemplate::submitSolution in 7b4d3249ce.

  Dropping it was suggested in https://github.com/bitcoin/bitcoin/pull/30200#issuecomment-2404460342

  2. `getTransactionsUpdated()`: this is used in the implementation of #31003 `waitFeesChanged`. It's not very useful generically because the mempool updates very frequently.

  3. `testBlockValidity()`: it might be useful for mining application to have a way to check the validity of a block template they modified, but the Stratum v2 Template Provider doesn't do that, and this method is a bit brittle (e.g. the block needs to build on the tip).

ACKs for top commit:
  TheCharlatan:
    Re-ACK c991cea1a0
  ryanofsky:
    Code review ACK c991cea1a0. Since last review, just rebased to avoid conflicts in surrounding code, and edited a commit message
  tdb3:
    code review ACK c991cea1a0

Tree-SHA512: 2138e54f920b26e01c068b24498c6a210c5c4358138dce0702ab58185d9ae148a18f04c97ac9f043646d40f8031618d80a718a176b1ce4779c237de6fb9c4a67

src/interfaces/mining.h

@@ -93,31 +93,6 @@ public:
      */
     virtual std::unique_ptr<BlockTemplate> createNewBlock(const node::BlockCreateOptions& options = {}) = 0;
 
-    /**
-     * Processes new block. A valid new block is automatically relayed to peers.
-     *
-     * @param[in]   block The block we want to process.
-     * @param[out]  new_block A boolean which is set to indicate if the block was first received via this call
-     * @returns     If the block was processed, independently of block validity
-     */
-    virtual bool processNewBlock(const std::shared_ptr<const CBlock>& block, bool* new_block) = 0;
-
-    //! Return the number of transaction updates in the mempool,
-    //! used to decide whether to make a new block template.
-    virtual unsigned int getTransactionsUpdated() = 0;
-
-    /**
-     * Check a block is completely valid from start to finish.
-     * Only works on top of our current best block.
-     * Does not check proof-of-work.
-     *
-     * @param[in] block the block to validate
-     * @param[in] check_merkle_root call CheckMerkleRoot()
-     * @param[out] state details of why a block failed to validate
-     * @returns false if it does not build on the current tip, or any of the checks fail
-     */
-    virtual bool testBlockValidity(const CBlock& block, bool check_merkle_root, BlockValidationState& state) = 0;
-
     //! Get internal node context. Useful for RPC and testing,
     //! but not accessible across processes.
     virtual node::NodeContext* context() { return nullptr; }

src/ipc/capnp/mining.capnp

@@ -18,9 +18,6 @@ interface Mining $Proxy.wrap("interfaces::Mining") {
     getTip @2 (context :Proxy.Context) -> (result: Common.BlockRef, hasResult: Bool);
     waitTipChanged @3 (context :Proxy.Context, currentTip: Data, timeout: Float64) -> (result: Common.BlockRef);
     createNewBlock @4 (options: BlockCreateOptions) -> (result: BlockTemplate);
-    processNewBlock @5 (context :Proxy.Context, block: Data) -> (newBlock: Bool, result: Bool);
-    getTransactionsUpdated @6 (context :Proxy.Context) -> (result: UInt32);
-    testBlockValidity @7 (context :Proxy.Context, block: Data, checkMerkleRoot: Bool) -> (state: BlockValidationState, result: Bool);
 }
 
 interface BlockTemplate $Proxy.wrap("interfaces::BlockTemplate") {

src/node/interfaces.cpp

@@ -979,29 +979,6 @@ public:
         return BlockRef{chainman().ActiveChain().Tip()->GetBlockHash(), chainman().ActiveChain().Tip()->nHeight};
     }
 
-    bool processNewBlock(const std::shared_ptr<const CBlock>& block, bool* new_block) override
-    {
-        return chainman().ProcessNewBlock(block, /*force_processing=*/true, /*min_pow_checked=*/true, /*new_block=*/new_block);
-    }
-
-    unsigned int getTransactionsUpdated() override
-    {
-        return context()->mempool->GetTransactionsUpdated();
-    }
-
-    bool testBlockValidity(const CBlock& block, bool check_merkle_root, BlockValidationState& state) override
-    {
-        LOCK(cs_main);
-        CBlockIndex* tip{chainman().ActiveChain().Tip()};
-        // Fail if the tip updated before the lock was taken
-        if (block.hashPrevBlock != tip->GetBlockHash()) {
-            state.Error("Block does not connect to current chain tip.");
-            return false;
-        }
-
-        return TestBlockValidity(state, chainman().GetParams(), chainman().ActiveChainstate(), block, tip, /*fCheckPOW=*/false, check_merkle_root);
-    }
-
     std::unique_ptr<BlockTemplate> createNewBlock(const BlockCreateOptions& options) override
     {
         BlockAssembler::Options assemble_options{options};

src/rpc/mining.cpp

@@ -131,7 +131,7 @@ static RPCHelpMan getnetworkhashps()
     };
 }
 
-static bool GenerateBlock(ChainstateManager& chainman, Mining& miner, CBlock&& block, uint64_t& max_tries, std::shared_ptr<const CBlock>& block_out, bool process_new_block)
+static bool GenerateBlock(ChainstateManager& chainman, CBlock&& block, uint64_t& max_tries, std::shared_ptr<const CBlock>& block_out, bool process_new_block)
 {
     block_out.reset();
     block.hashMerkleRoot = BlockMerkleRoot(block);
@@ -151,7 +151,7 @@ static bool GenerateBlock(ChainstateManager& chainman, Mining& miner, CBlock&& b
 
     if (!process_new_block) return true;
 
-    if (!miner.processNewBlock(block_out, nullptr)) {
+    if (!chainman.ProcessNewBlock(block_out, /*force_processing=*/true, /*min_pow_checked=*/true, nullptr)) {
         throw JSONRPCError(RPC_INTERNAL_ERROR, "ProcessNewBlock, block not accepted");
     }
 
@@ -166,7 +166,7 @@ static UniValue generateBlocks(ChainstateManager& chainman, Mining& miner, const
         CHECK_NONFATAL(block_template);
 
         std::shared_ptr<const CBlock> block_out;
-        if (!GenerateBlock(chainman, miner, block_template->getBlock(), nMaxTries, block_out, /*process_new_block=*/true)) {
+        if (!GenerateBlock(chainman, block_template->getBlock(), nMaxTries, block_out, /*process_new_block=*/true)) {
             break;
         }
 
@@ -384,16 +384,17 @@ static RPCHelpMan generateblock()
     RegenerateCommitments(block, chainman);
 
     {
+        LOCK(::cs_main);
         BlockValidationState state;
-        if (!miner.testBlockValidity(block, /*check_merkle_root=*/false, state)) {
+        if (!TestBlockValidity(state, chainman.GetParams(), chainman.ActiveChainstate(), block, chainman.m_blockman.LookupBlockIndex(block.hashPrevBlock),  /*fCheckPOW=*/false, /*fCheckMerkleRoot=*/false)) {
-            throw JSONRPCError(RPC_VERIFY_ERROR, strprintf("testBlockValidity failed: %s", state.ToString()));
+            throw JSONRPCError(RPC_VERIFY_ERROR, strprintf("TestBlockValidity failed: %s", state.ToString()));
         }
     }
 
     std::shared_ptr<const CBlock> block_out;
     uint64_t max_tries{DEFAULT_MAX_TRIES};
 
-    if (!GenerateBlock(chainman, miner, std::move(block), max_tries, block_out, process_new_block) || !block_out) {
+    if (!GenerateBlock(chainman, std::move(block), max_tries, block_out, process_new_block) || !block_out) {
         throw JSONRPCError(RPC_MISC_ERROR, "Failed to make block.");
     }
 
@@ -709,12 +710,12 @@ static RPCHelpMan getblocktemplate()
                 return "duplicate-inconclusive";
             }
 
-            // testBlockValidity only supports blocks built on the current Tip
+            // TestBlockValidity only supports blocks built on the current Tip
             if (block.hashPrevBlock != tip) {
                 return "inconclusive-not-best-prevblk";
             }
             BlockValidationState state;
-            miner.testBlockValidity(block, /*check_merkle_root=*/true, state);
+            TestBlockValidity(state, chainman.GetParams(), chainman.ActiveChainstate(), block, chainman.m_blockman.LookupBlockIndex(block.hashPrevBlock), /*fCheckPOW=*/false, /*fCheckMerkleRoot=*/true);
             return BIP22ValidationResult(state);
         }
 
@@ -742,6 +743,7 @@ static RPCHelpMan getblocktemplate()
     }
 
     static unsigned int nTransactionsUpdatedLast;
+    const CTxMemPool& mempool = EnsureMemPool(node);
 
     if (!lpval.isNull())
     {
@@ -772,7 +774,7 @@ static RPCHelpMan getblocktemplate()
                 tip = miner.waitTipChanged(hashWatchedChain, checktxtime).hash;
                 // Timeout: Check transactions for update
                 // without holding the mempool lock to avoid deadlocks
-                if (miner.getTransactionsUpdated() != nTransactionsUpdatedLastLP)
+                if (mempool.GetTransactionsUpdated() != nTransactionsUpdatedLastLP)
                     break;
                 checktxtime = std::chrono::seconds(10);
             }
@@ -803,13 +805,13 @@ static RPCHelpMan getblocktemplate()
     static int64_t time_start;
     static std::unique_ptr<BlockTemplate> block_template;
     if (!pindexPrev || pindexPrev->GetBlockHash() != tip ||
-        (miner.getTransactionsUpdated() != nTransactionsUpdatedLast && GetTime() - time_start > 5))
+        (mempool.GetTransactionsUpdated() != nTransactionsUpdatedLast && GetTime() - time_start > 5))
     {
         // Clear pindexPrev so future calls make a new block, despite any failures from here on
         pindexPrev = nullptr;
 
         // Store the pindexBest used before createNewBlock, to avoid races
-        nTransactionsUpdatedLast = miner.getTransactionsUpdated();
+        nTransactionsUpdatedLast = mempool.GetTransactionsUpdated();
         CBlockIndex* pindexPrevNew = chainman.m_blockman.LookupBlockIndex(tip);
         time_start = GetTime();
 
@@ -1032,13 +1034,10 @@ static RPCHelpMan submitblock()
         }
     }
 
-    NodeContext& node = EnsureAnyNodeContext(request.context);
-    Mining& miner = EnsureMining(node);
-
     bool new_block;
     auto sc = std::make_shared<submitblock_StateCatcher>(block.GetHash());
     CHECK_NONFATAL(chainman.m_options.signals)->RegisterSharedValidationInterface(sc);
-    bool accepted = miner.processNewBlock(blockptr, /*new_block=*/&new_block);
+    bool accepted = chainman.ProcessNewBlock(blockptr, /*force_processing=*/true, /*min_pow_checked=*/true, /*new_block=*/&new_block);
     CHECK_NONFATAL(chainman.m_options.signals)->UnregisterSharedValidationInterface(sc);
     if (!new_block && accepted) {
         return "duplicate";

test/functional/rpc_generate.py

@@ -87,7 +87,7 @@ class RPCGenerateTest(BitcoinTestFramework):
         txid1 = miniwallet.send_self_transfer(from_node=node)['txid']
         utxo1 = miniwallet.get_utxo(txid=txid1)
         rawtx2 = miniwallet.create_self_transfer(utxo_to_spend=utxo1)['hex']
-        assert_raises_rpc_error(-25, 'testBlockValidity failed: bad-txns-inputs-missingorspent', self.generateblock, node, address, [rawtx2, txid1])
+        assert_raises_rpc_error(-25, 'TestBlockValidity failed: bad-txns-inputs-missingorspent', self.generateblock, node, address, [rawtx2, txid1])
 
         self.log.info('Fail to generate block with txid not in mempool')
         missing_txid = '0000000000000000000000000000000000000000000000000000000000000000'