feat: implement new RPC getislocks and add hex field to RPC getbestchainlock

doc/release-notes-6455.md

@@ -0,0 +1,11 @@
+## New RPCs
+
+- **`getislocks`**
+    - Retrieves the InstantSend lock data for the given transaction IDs (txids).
+    Returns the lock information in both human-friendly JSON format and binary hex-encoded zmq-compatible format.
+
+## Updated RPCs
+
+- **`getbestchainlock` Changes**
+    - A new hex field has been added to the getbestchainlock RPC, which returns the ChainLock information in zmq-compatible, hex-encoded binary format.
+

src/rpc/blockchain.cpp

@@ -241,29 +241,38 @@ static RPCHelpMan getbestchainlock()
                 {RPCResult::Type::NUM, "height", "The block height or index"},
                 {RPCResult::Type::STR_HEX, "signature", "The ChainLock's BLS signature"},
                 {RPCResult::Type::BOOL, "known_block", "True if the block is known by our node"},
+                {RPCResult::Type::STR_HEX, "hex", "The serialized, hex-encoded data for best ChainLock"},
             }},
         RPCExamples{
             HelpExampleCli("getbestchainlock", "")
             + HelpExampleRpc("getbestchainlock", "")
         },
     [&](const RPCHelpMan& self, const JSONRPCRequest& request) -> UniValue
 {
-    UniValue result(UniValue::VOBJ);
-
     const NodeContext& node = EnsureAnyNodeContext(request.context);
 
     const LLMQContext& llmq_ctx = EnsureLLMQContext(node);
     const llmq::CChainLockSig clsig = llmq_ctx.clhandler->GetBestChainLock();
     if (clsig.IsNull()) {
         throw JSONRPCError(RPC_INTERNAL_ERROR, "Unable to find any ChainLock");
     }
+
+    UniValue result(UniValue::VOBJ);
+
     result.pushKV("blockhash", clsig.getBlockHash().GetHex());
     result.pushKV("height", clsig.getHeight());
     result.pushKV("signature", clsig.getSig().ToString());
 
-    const ChainstateManager& chainman = EnsureChainman(node);
-    LOCK(cs_main);
-    result.pushKV("known_block", chainman.m_blockman.LookupBlockIndex(clsig.getBlockHash()) != nullptr);
+    {
+        const ChainstateManager& chainman = EnsureChainman(node);
+        LOCK(cs_main);
+        result.pushKV("known_block", chainman.m_blockman.LookupBlockIndex(clsig.getBlockHash()) != nullptr);
+    }
+
+    CDataStream ssTx(SER_NETWORK, PROTOCOL_VERSION);
+    ssTx << clsig;
+    result.pushKV("hex", HexStr(ssTx));
+
     return result;
 },
     };

src/rpc/client.cpp

@@ -115,6 +115,7 @@ static const CRPCConvertParam vRPCConvertParams[] =
     { "gettransaction", 1, "include_watchonly" },
     { "gettransaction", 2, "verbose" },
     { "getrawtransaction", 1, "verbose" },
+    { "getislocks", 0, "txids" },
     { "getrawtransactionmulti", 0, "transactions" },
     { "getrawtransactionmulti", 1, "verbose" },
     { "gettxchainlocks", 0, "txids" },

src/rpc/rawtransaction.cpp

@@ -300,6 +300,7 @@ static RPCHelpMan getrawtransactionmulti() {
                     {"verbose", RPCArg::Type::BOOL, RPCArg::Default{false},
                      "If false, return a string, otherwise return a json object"},
             },
+            // TODO: replace RPCResults to proper annotation
             RPCResults{},
             RPCExamples{
                     HelpExampleCli("getrawtransactionmulti",
@@ -366,6 +367,86 @@ static RPCHelpMan getrawtransactionmulti() {
     };
 }
 
+static RPCHelpMan getislocks()
+{
+    return RPCHelpMan{"getislocks",
+        "\nReturns the raw InstantSend lock data for each txids. Returns Null if there is no known IS yet.",
+        {
+            {"txids", RPCArg::Type::ARR, RPCArg::Optional::NO, "The transaction ids (no more than 100)",
+                {
+                    {"txid", RPCArg::Type::STR_HEX, RPCArg::Optional::OMITTED, "A transaction hash"},
+                },
+            },
+        },
+        RPCResult{
+            RPCResult::Type::ARR, "", "Response is an array with the same size as the input txids",
+                {{RPCResult::Type::OBJ, "", "",
+                {
+                    {RPCResult::Type::STR_HEX, "txid", "The transaction id"},
+                    {RPCResult::Type::ARR, "inputs", "The inputs",
+                    {
+                        {RPCResult::Type::OBJ, "", "",
+                            {
+                                {RPCResult::Type::STR_HEX, "txid", "The transaction id"},
+                                {RPCResult::Type::NUM, "vout", "The output number"},
+                            },
+                        },
+                    }},
+                    {RPCResult::Type::STR_HEX, "cycleHash", "The Cycle Hash"},
+                    {RPCResult::Type::STR_HEX, "signature", "The InstantSend's BLS signature"},
+                    {RPCResult::Type::STR_HEX, "hex", "The serialized, hex-encoded data for 'txid'"},
+                }},
+                RPCResult{"if no InstantSend Lock is known for specified txid",
+                     RPCResult::Type::STR, "data", "Just 'None' string"
+                },
+            }},
+        RPCExamples{
+            HelpExampleCli("getislocks", "'[\"txid\",...]'")
+            + HelpExampleRpc("getislocks", "'[\"txid\",...]'")
+        },
+    [&](const RPCHelpMan& self, const JSONRPCRequest& request) -> UniValue
+{
+    const NodeContext& node = EnsureAnyNodeContext(request.context);
+
+    UniValue result_arr(UniValue::VARR);
+    UniValue txids = request.params[0].get_array();
+    if (txids.size() > 100) {
+        throw JSONRPCError(RPC_INVALID_PARAMETER, "Up to 100 txids only");
+    }
+
+    const LLMQContext& llmq_ctx = EnsureLLMQContext(node);
+    for (const auto idx : irange::range(txids.size())) {
+        const uint256 txid(ParseHashV(txids[idx], "txid"));
+
+        if (const llmq::CInstantSendLockPtr islock = llmq_ctx.isman->GetInstantSendLockByTxid(txid); islock != nullptr) {
+            UniValue objIS(UniValue::VOBJ);
+            objIS.pushKV("txid", islock->txid.ToString());
+            UniValue inputs(UniValue::VARR);
+            for (const auto out : islock->inputs) {
+                UniValue outpoint(UniValue::VOBJ);
+                outpoint.pushKV("txid", out.hash.ToString());
+                outpoint.pushKV("vout", static_cast<int64_t>(out.n));
+                inputs.push_back(outpoint);
+            }
+            objIS.pushKV("inputs", inputs);
+            objIS.pushKV("cycleHash", islock->cycleHash.ToString());
+            objIS.pushKV("signature", islock->sig.ToString());
+            {
+                CDataStream ssTx(SER_NETWORK, PROTOCOL_VERSION);
+                ssTx << *islock;
+                objIS.pushKV("hex", HexStr(ssTx));
+            }
+            result_arr.push_back(objIS);
+        } else {
+            result_arr.push_back("None");
+        }
+    }
+    return result_arr;
+
+},
+    };
+}
+
 static RPCHelpMan gettxchainlocks()
 {
     return RPCHelpMan{
@@ -2088,6 +2169,7 @@ static const CRPCCommand commands[] =
     { "rawtransactions",     &getassetunlockstatuses,     },
     { "rawtransactions",     &getrawtransaction,          },
     { "rawtransactions",     &getrawtransactionmulti,     },
+    { "rawtransactions",     &getislocks,                 },
     { "rawtransactions",     &gettxchainlocks,            },
     { "rawtransactions",     &createrawtransaction,       },
     { "rawtransactions",     &decoderawtransaction,       },

test/functional/interface_zmq_dash.py

@@ -136,6 +136,8 @@ def run_test(self):
             self.zmq_context = zmq.Context()
             # Initialize the network
             self.nodes[0].sporkupdate("SPORK_17_QUORUM_DKG_ENABLED", 0)
+            self.log.info("Test RPC hex getbestchainlock before any CL appeared")
+            assert_raises_rpc_error(-32603, "Unable to find any ChainLock", self.nodes[0].getbestchainlock)
             self.wait_for_sporks_same()
             self.activate_v19(expected_activation_height=900)
             self.log.info("Activated v19 at height:" + str(self.nodes[0].getblockcount()))
@@ -263,6 +265,7 @@ def test_chainlock_publishers(self):
         assert_equal(uint256_to_string(zmq_chain_lock.blockHash), rpc_chain_lock_hash)
         assert_equal(zmq_chain_locked_block.hash, rpc_chain_lock_hash)
         assert_equal(zmq_chain_lock.sig.hex(), rpc_best_chain_lock_sig)
+        assert_equal(zmq_chain_lock.serialize().hex(), self.nodes[0].getbestchainlock()['hex'])
         # Unsubscribe from ChainLock messages
         self.unsubscribe(chain_lock_publishers)
 
@@ -285,6 +288,7 @@ def test_instantsend_publishers(self):
         # Create two raw TXs, they will conflict with each other
         rpc_raw_tx_1 = self.create_raw_tx(self.nodes[0], self.nodes[0], 1, 1, 100)
         rpc_raw_tx_2 = self.create_raw_tx(self.nodes[0], self.nodes[0], 1, 1, 100)
+        assert_equal(['None'], self.nodes[0].getislocks([rpc_raw_tx_1['txid']]))
         # Send the first transaction and wait for the InstantLock
         rpc_raw_tx_1_hash = self.nodes[0].sendrawtransaction(rpc_raw_tx_1['hex'])
         self.wait_for_instantlock(rpc_raw_tx_1_hash, self.nodes[0])
@@ -304,6 +308,8 @@ def test_instantsend_publishers(self):
         assert_equal(zmq_tx_lock_tx.hash, rpc_raw_tx_1['txid'])
         zmq_tx_lock = msg_isdlock()
         zmq_tx_lock.deserialize(zmq_tx_lock_sig_stream)
+        assert_equal(rpc_raw_tx_1['txid'], self.nodes[0].getislocks([rpc_raw_tx_1['txid']])[0]['txid'])
+        assert_equal(zmq_tx_lock.serialize().hex(), self.nodes[0].getislocks([rpc_raw_tx_1['txid']])[0]['hex'])
         assert_equal(uint256_to_string(zmq_tx_lock.txid), rpc_raw_tx_1['txid'])
         # Try to send the second transaction. This must throw an RPC error because it conflicts with rpc_raw_tx_1
         # which already got the InstantSend lock.