Introduce Mining interface

Start out with a single method isTestChain() that's used by the getblocktemplate RPC.

14 files changed, 85 insertions, 3 deletions

diff --git a/doc/developer-notes.md b/doc/developer-notes.md
index eb2bb41aa4..d9d5b392c5 100644
--- a/doc/developer-notes.md
+++ b/doc/developer-notes.md
@@ -1457,8 +1457,9 @@ independent (node, wallet, GUI), are defined in
 there are [`interfaces::Chain`](../src/interfaces/chain.h), used by wallet to
 access the node's latest chain state,
 [`interfaces::Node`](../src/interfaces/node.h), used by the GUI to control the
-node, and [`interfaces::Wallet`](../src/interfaces/wallet.h), used by the GUI
-to control an individual wallet. There are also more specialized interface
+node, [`interfaces::Wallet`](../src/interfaces/wallet.h), used by the GUI
+to control an individual wallet and [`interfaces::Mining`](../src/interfaces/mining.h),
+used by RPC to generate block templates. There are also more specialized interface
 types like [`interfaces::Handler`](../src/interfaces/handler.h)
 [`interfaces::ChainClient`](../src/interfaces/chain.h) passed to and from
 various interface methods.
diff --git a/src/Makefile.am b/src/Makefile.am
index 4a1973aa87..f95a6fa123 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -177,6 +177,7 @@ BITCOIN_CORE_H = \
   interfaces/handler.h \
   interfaces/init.h \
   interfaces/ipc.h \
+  interfaces/mining.h \
   interfaces/node.h \
   interfaces/wallet.h \
   kernel/blockmanager_opts.h \
diff --git a/src/init.cpp b/src/init.cpp
index 5bb82dc320..0c57dfea7f 100644
--- a/src/init.cpp
+++ b/src/init.cpp
@@ -31,6 +31,7 @@
 #include <init/common.h>
 #include <interfaces/chain.h>
 #include <interfaces/init.h>
+#include <interfaces/mining.h>
 #include <interfaces/node.h>
 #include <kernel/context.h>
 #include <key.h>
@@ -1117,6 +1118,7 @@ bool AppInitLockDataDirectory()
 bool AppInitInterfaces(NodeContext& node)
 {
     node.chain = node.init->makeChain();
+    node.mining = node.init->makeMining();
     return true;
 }
 
diff --git a/src/init/bitcoin-node.cpp b/src/init/bitcoin-node.cpp
index 97b8dc1161..00a3822791 100644
--- a/src/init/bitcoin-node.cpp
+++ b/src/init/bitcoin-node.cpp
@@ -30,6 +30,7 @@ public:
     }
     std::unique_ptr<interfaces::Node> makeNode() override { return interfaces::MakeNode(m_node); }
     std::unique_ptr<interfaces::Chain> makeChain() override { return interfaces::MakeChain(m_node); }
+    std::unique_ptr<interfaces::Mining> makeMining() override { return interfaces::MakeMining(m_node); }
     std::unique_ptr<interfaces::WalletLoader> makeWalletLoader(interfaces::Chain& chain) override
     {
         return MakeWalletLoader(chain, *Assert(m_node.args));
diff --git a/src/init/bitcoin-qt.cpp b/src/init/bitcoin-qt.cpp
index 3003a8fde1..5209c72973 100644
--- a/src/init/bitcoin-qt.cpp
+++ b/src/init/bitcoin-qt.cpp
@@ -6,6 +6,7 @@
 #include <interfaces/chain.h>
 #include <interfaces/echo.h>
 #include <interfaces/init.h>
+#include <interfaces/mining.h>
 #include <interfaces/node.h>
 #include <interfaces/wallet.h>
 #include <node/context.h>
@@ -25,6 +26,7 @@ public:
     }
     std::unique_ptr<interfaces::Node> makeNode() override { return interfaces::MakeNode(m_node); }
     std::unique_ptr<interfaces::Chain> makeChain() override { return interfaces::MakeChain(m_node); }
+    std::unique_ptr<interfaces::Mining> makeMining() override { return interfaces::MakeMining(m_node); }
     std::unique_ptr<interfaces::WalletLoader> makeWalletLoader(interfaces::Chain& chain) override
     {
         return MakeWalletLoader(chain, *Assert(m_node.args));
diff --git a/src/init/bitcoind.cpp b/src/init/bitcoind.cpp
index b5df764017..48be8831d2 100644
--- a/src/init/bitcoind.cpp
+++ b/src/init/bitcoind.cpp
@@ -6,6 +6,7 @@
 #include <interfaces/chain.h>
 #include <interfaces/echo.h>
 #include <interfaces/init.h>
+#include <interfaces/mining.h>
 #include <interfaces/node.h>
 #include <interfaces/wallet.h>
 #include <node/context.h>
@@ -27,6 +28,7 @@ public:
     }
     std::unique_ptr<interfaces::Node> makeNode() override { return interfaces::MakeNode(m_node); }
     std::unique_ptr<interfaces::Chain> makeChain() override { return interfaces::MakeChain(m_node); }
+    std::unique_ptr<interfaces::Mining> makeMining() override { return interfaces::MakeMining(m_node); }
     std::unique_ptr<interfaces::WalletLoader> makeWalletLoader(interfaces::Chain& chain) override
     {
         return MakeWalletLoader(chain, *Assert(m_node.args));
diff --git a/src/interfaces/init.h b/src/interfaces/init.h
index addc45aa26..094ead399d 100644
--- a/src/interfaces/init.h
+++ b/src/interfaces/init.h
@@ -7,6 +7,7 @@
 
 #include <interfaces/chain.h>
 #include <interfaces/echo.h>
+#include <interfaces/mining.h>
 #include <interfaces/node.h>
 #include <interfaces/wallet.h>
 
@@ -32,6 +33,7 @@ public:
     virtual ~Init() = default;
     virtual std::unique_ptr<Node> makeNode() { return nullptr; }
     virtual std::unique_ptr<Chain> makeChain() { return nullptr; }
+    virtual std::unique_ptr<Mining> makeMining() { return nullptr; }
     virtual std::unique_ptr<WalletLoader> makeWalletLoader(Chain& chain) { return nullptr; }
     virtual std::unique_ptr<Echo> makeEcho() { return nullptr; }
     virtual Ipc* ipc() { return nullptr; }
diff --git a/src/interfaces/mining.h b/src/interfaces/mining.h
new file mode 100644
index 0000000000..afcd8d1cda
--- /dev/null
+++ b/src/interfaces/mining.h
@@ -0,0 +1,35 @@
+// Copyright (c) 2024 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#ifndef BITCOIN_INTERFACES_MINING_H
+#define BITCOIN_INTERFACES_MINING_H
+
+namespace node {
+struct NodeContext;
+} // namespace node
+
+namespace interfaces {
+
+//! Interface giving clients (RPC, Stratum v2 Template Provider in the future)
+//! ability to create block templates.
+
+class Mining
+{
+public:
+    virtual ~Mining() {}
+
+    //! If this chain is exclusively used for testing
+    virtual bool isTestChain() = 0;
+
+    //! Get internal node context. Useful for RPC and testing,
+    //! but not accessible across processes.
+    virtual node::NodeContext* context() { return nullptr; }
+};
+
+//! Return implementation of Mining interface.
+std::unique_ptr<Mining> MakeMining(node::NodeContext& node);
+
+} // namespace interfaces
+
+#endif // BITCOIN_INTERFACES_MINING_H
diff --git a/src/node/context.cpp b/src/node/context.cpp
index da05fde6ee..75dfaee866 100644
--- a/src/node/context.cpp
+++ b/src/node/context.cpp
@@ -7,6 +7,7 @@
 #include <addrman.h>
 #include <banman.h>
 #include <interfaces/chain.h>
+#include <interfaces/mining.h>
 #include <kernel/context.h>
 #include <key.h>
 #include <net.h>
diff --git a/src/node/context.h b/src/node/context.h
index 77838ea99b..a664fad80b 100644
--- a/src/node/context.h
+++ b/src/node/context.h
@@ -27,6 +27,7 @@ class PeerManager;
 namespace interfaces {
 class Chain;
 class ChainClient;
+class Mining;
 class Init;
 class WalletLoader;
 } // namespace interfaces
@@ -74,6 +75,7 @@ struct NodeContext {
     std::vector<std::unique_ptr<interfaces::ChainClient>> chain_clients;
     //! Reference to chain client that should used to load or create wallets
     //! opened by the gui.
+    std::unique_ptr<interfaces::Mining> mining;
     interfaces::WalletLoader* wallet_loader{nullptr};
     std::unique_ptr<CScheduler> scheduler;
     std::function<void()> rpc_interruption_point = [] {};
diff --git a/src/node/interfaces.cpp b/src/node/interfaces.cpp
index 2b36f4ceae..e44cb51873 100644
--- a/src/node/interfaces.cpp
+++ b/src/node/interfaces.cpp
@@ -14,6 +14,7 @@
 #include <init.h>
 #include <interfaces/chain.h>
 #include <interfaces/handler.h>
+#include <interfaces/mining.h>
 #include <interfaces/node.h>
 #include <interfaces/wallet.h>
 #include <kernel/chain.h>
@@ -69,6 +70,7 @@ using interfaces::Chain;
 using interfaces::FoundBlock;
 using interfaces::Handler;
 using interfaces::MakeSignalHandler;
+using interfaces::Mining;
 using interfaces::Node;
 using interfaces::WalletLoader;
 using util::Join;
@@ -831,10 +833,26 @@ public:
     ValidationSignals& validation_signals() { return *Assert(m_node.validation_signals); }
     NodeContext& m_node;
 };
+
+class MinerImpl : public Mining
+{
+public:
+    explicit MinerImpl(NodeContext& node) : m_node(node) {}
+
+    bool isTestChain() override
+    {
+        return chainman().GetParams().IsTestChain();
+    }
+
+    NodeContext* context() override { return &m_node; }
+    ChainstateManager& chainman() { return *Assert(m_node.chainman); }
+    NodeContext& m_node;
+};
 } // namespace
 } // namespace node
 
 namespace interfaces {
 std::unique_ptr<Node> MakeNode(node::NodeContext& context) { return std::make_unique<node::NodeImpl>(context); }
 std::unique_ptr<Chain> MakeChain(node::NodeContext& context) { return std::make_unique<node::ChainImpl>(context); }
+std::unique_ptr<Mining> MakeMining(node::NodeContext& context) { return std::make_unique<node::MinerImpl>(context); }
 } // namespace interfaces
diff --git a/src/rpc/mining.cpp b/src/rpc/mining.cpp
index 0f6853ef37..0e9d4829d2 100644
--- a/src/rpc/mining.cpp
+++ b/src/rpc/mining.cpp
@@ -16,6 +16,7 @@
 #include <core_io.h>
 #include <deploymentinfo.h>
 #include <deploymentstatus.h>
+#include <interfaces/mining.h>
 #include <key_io.h>
 #include <net.h>
 #include <node/context.h>
@@ -45,6 +46,7 @@
 
 using node::BlockAssembler;
 using node::CBlockTemplate;
+using interfaces::Mining;
 using node::NodeContext;
 using node::RegenerateCommitments;
 using node::UpdateTime;
@@ -724,7 +726,8 @@ static RPCHelpMan getblocktemplate()
     if (strMode != "template")
         throw JSONRPCError(RPC_INVALID_PARAMETER, "Invalid mode");
 
-    if (!chainman.GetParams().IsTestChain()) {
+    Mining& miner = EnsureMining(node);
+    if (!miner.isTestChain()) {
         const CConnman& connman = EnsureConnman(node);
         if (connman.GetNodeCount(ConnectionDirection::Both) == 0) {
             throw JSONRPCError(RPC_CLIENT_NOT_CONNECTED, PACKAGE_NAME " is not connected!");
diff --git a/src/rpc/server_util.cpp b/src/rpc/server_util.cpp
index efd4a43c28..0387cbb8e2 100644
--- a/src/rpc/server_util.cpp
+++ b/src/rpc/server_util.cpp
@@ -101,6 +101,14 @@ CConnman& EnsureConnman(const NodeContext& node)
     return *node.connman;
 }
 
+interfaces::Mining& EnsureMining(const NodeContext& node)
+{
+    if (!node.mining) {
+        throw JSONRPCError(RPC_INTERNAL_ERROR, "Node miner not found");
+    }
+    return *node.mining;
+}
+
 PeerManager& EnsurePeerman(const NodeContext& node)
 {
     if (!node.peerman) {
diff --git a/src/rpc/server_util.h b/src/rpc/server_util.h
index a4a53166b4..1e6fb7e6a6 100644
--- a/src/rpc/server_util.h
+++ b/src/rpc/server_util.h
@@ -18,6 +18,9 @@ class BanMan;
 namespace node {
 struct NodeContext;
 } // namespace node
+namespace interfaces {
+class Mining;
+} // namespace interfaces
 
 node::NodeContext& EnsureAnyNodeContext(const std::any& context);
 CTxMemPool& EnsureMemPool(const node::NodeContext& node);
@@ -31,6 +34,7 @@ ChainstateManager& EnsureAnyChainman(const std::any& context);
 CBlockPolicyEstimator& EnsureFeeEstimator(const node::NodeContext& node);
 CBlockPolicyEstimator& EnsureAnyFeeEstimator(const std::any& context);
 CConnman& EnsureConnman(const node::NodeContext& node);
+interfaces::Mining& EnsureMining(const node::NodeContext& node);
 PeerManager& EnsurePeerman(const node::NodeContext& node);
 AddrMan& EnsureAddrman(const node::NodeContext& node);
 AddrMan& EnsureAnyAddrman(const std::any& context);