Merge #19717: rpc: Assert that RPCArg names are equal to CRPCCommand ones (mining,zmq,rpcdump)

fa3d9ce3254882c545d700990fe8e9a678f31eed rpc: Assert that RPCArg names are equal to CRPCCommand ones (rpcdump) (MarcoFalke)
fa32c1d5ec25bc53bf989a8ae68e688593d2859d rpc: Assert that RPCArg names are equal to CRPCCommand ones (zmq) (MarcoFalke)
faaa46dc204d6d714f71dbc6f0bf02215dba0f0f rpc: Assert that RPCArg names are equal to CRPCCommand ones (mining) (MarcoFalke)
fa93bc14c7411a108dd024d391344fabf0f76369 rpc: Remove unused return type from appendCommand (MarcoFalke)

Pull request description:

  This is split out from #18531 to just touch the RPC methods in misc. Description from the main pr:

  ### Motivation

  RPCArg names in the rpc help are currently only used for documentation. However, in the future they could be used to teach the server the named arguments. Named arguments are currently registered by the `CRPCCommand`s and duplicate the RPCArg names from the documentation. This redundancy is fragile, and has lead to errors in the past (despite having linters to catch those kind of errors). See section "bugs found" for a list of bugs that have been found as a result of the changes here.

  ### Changes

  The changes here add an assert in the `CRPCCommand` constructor that the RPCArg names are identical to the ones in the `CRPCCommand`.

  ### Future work

  > Here or follow up, makes sense to also assert type of returned UniValue?

  Sure, but let's not get ahead of ourselves. I am going to submit any further works as follow-ups, including:

  * Removing the CRPCCommand arguments, now that they are asserted to be equal and thus redundant
  * Removing all python regex linters on the args, now that RPCMan can be used to generate any output, including the cli.cpp table
  * Auto-formatting and sanity checking the RPCExamples with RPCMan
  * Checking passed-in json in self-check. Removing redundant checks
  * Checking returned json against documentation to avoid regressions or false documentation
  * Compile the RPC documentation at compile-time to ensure it doesn't change at runtime and is completely static

  ### Bugs found

  * The assert identified issue #18607
  * The changes itself fixed bug #19250

ACKs for top commit:
  fjahr:
    tested ACK fa3d9ce3254882c545d700990fe8e9a678f31eed
  promag:
    Code review ACK fa3d9ce3254882c545d700990fe8e9a678f31eed.

Tree-SHA512: 068ade4b55cc195868d53b7f9a27151d45b440857bb069e261a49d102a49a38fdba5d68868516a1d66a54a73ba34681362f934ded7349e894042bde873b75719

3 files changed, 76 insertions, 56 deletions

diff --git a/src/rpc/mining.cpp b/src/rpc/mining.cpp
index d9cc6f8832..b04e106b2d 100644
--- a/src/rpc/mining.cpp
+++ b/src/rpc/mining.cpp
@@ -81,9 +81,9 @@ static UniValue GetNetworkHashPS(int lookup, int height) {
     return workDiff.getdouble() / timeDiff;
 }
 
-static UniValue getnetworkhashps(const JSONRPCRequest& request)
+static RPCHelpMan getnetworkhashps()
 {
-            RPCHelpMan{"getnetworkhashps",
+    return RPCHelpMan{"getnetworkhashps",
                 "\nReturns the estimated network hashes per second based on the last n blocks.\n"
                 "Pass in [blocks] to override # of blocks, -1 specifies since last difficulty change.\n"
                 "Pass in [height] to estimate the network speed at the time when a certain block was found.\n",
@@ -97,10 +97,12 @@ static UniValue getnetworkhashps(const JSONRPCRequest& request)
                     HelpExampleCli("getnetworkhashps", "")
             + HelpExampleRpc("getnetworkhashps", "")
                 },
-            }.Check(request);
-
+        [&](const RPCHelpMan& self, const JSONRPCRequest& request) -> UniValue
+{
     LOCK(cs_main);
     return GetNetworkHashPS(!request.params[0].isNull() ? request.params[0].get_int() : 120, !request.params[1].isNull() ? request.params[1].get_int() : -1);
+},
+    };
 }
 
 static bool GenerateBlock(ChainstateManager& chainman, CBlock& block, uint64_t& max_tries, unsigned int& extra_nonce, uint256& block_hash)
@@ -200,9 +202,9 @@ static bool getScriptFromDescriptor(const std::string& descriptor, CScript& scri
     }
 }
 
-static UniValue generatetodescriptor(const JSONRPCRequest& request)
+static RPCHelpMan generatetodescriptor()
 {
-    RPCHelpMan{
+    return RPCHelpMan{
         "generatetodescriptor",
         "\nMine blocks immediately to a specified descriptor (before the RPC call returns)\n",
         {
@@ -218,9 +220,8 @@ static UniValue generatetodescriptor(const JSONRPCRequest& request)
         },
         RPCExamples{
             "\nGenerate 11 blocks to mydesc\n" + HelpExampleCli("generatetodescriptor", "11 \"mydesc\"")},
-    }
-        .Check(request);
-
+        [&](const RPCHelpMan& self, const JSONRPCRequest& request) -> UniValue
+{
     const int num_blocks{request.params[0].get_int()};
     const uint64_t max_tries{request.params[2].isNull() ? DEFAULT_MAX_TRIES : request.params[2].get_int()};
 
@@ -234,22 +235,25 @@ static UniValue generatetodescriptor(const JSONRPCRequest& request)
     ChainstateManager& chainman = EnsureChainman(request.context);
 
     return generateBlocks(chainman, mempool, coinbase_script, num_blocks, max_tries);
+},
+    };
 }
 
-static UniValue generate(const JSONRPCRequest& request)
+static RPCHelpMan generate()
 {
-    const std::string help_str{"generate ( nblocks maxtries ) has been replaced by the -generate cli option. Refer to -help for more information."};
+    return RPCHelpMan{"generate", "has been replaced by the -generate cli option. Refer to -help for more information.", {}, {}, RPCExamples{""}, [&](const RPCHelpMan& self, const JSONRPCRequest& request) -> UniValue {
 
     if (request.fHelp) {
-        throw std::runtime_error(help_str);
+        throw std::runtime_error(self.ToString());
     } else {
-        throw JSONRPCError(RPC_METHOD_NOT_FOUND, help_str);
+        throw JSONRPCError(RPC_METHOD_NOT_FOUND, self.ToString());
     }
+    }};
 }
 
-static UniValue generatetoaddress(const JSONRPCRequest& request)
+static RPCHelpMan generatetoaddress()
 {
-            RPCHelpMan{"generatetoaddress",
+    return RPCHelpMan{"generatetoaddress",
                 "\nMine blocks immediately to a specified address (before the RPC call returns)\n",
                 {
                     {"nblocks", RPCArg::Type::NUM, RPCArg::Optional::NO, "How many blocks are generated immediately."},
@@ -267,8 +271,8 @@ static UniValue generatetoaddress(const JSONRPCRequest& request)
             + "If you are using the " PACKAGE_NAME " wallet, you can get a new address to send the newly generated bitcoin to with:\n"
             + HelpExampleCli("getnewaddress", "")
                 },
-            }.Check(request);
-
+        [&](const RPCHelpMan& self, const JSONRPCRequest& request) -> UniValue
+{
     const int num_blocks{request.params[0].get_int()};
     const uint64_t max_tries{request.params[2].isNull() ? DEFAULT_MAX_TRIES : request.params[2].get_int()};
 
@@ -283,11 +287,13 @@ static UniValue generatetoaddress(const JSONRPCRequest& request)
     CScript coinbase_script = GetScriptForDestination(destination);
 
     return generateBlocks(chainman, mempool, coinbase_script, num_blocks, max_tries);
+},
+    };
 }
 
-static UniValue generateblock(const JSONRPCRequest& request)
+static RPCHelpMan generateblock()
 {
-    RPCHelpMan{"generateblock",
+    return RPCHelpMan{"generateblock",
         "\nMine a block with a set of ordered transactions immediately to a specified address or descriptor (before the RPC call returns)\n",
         {
             {"output", RPCArg::Type::STR, RPCArg::Optional::NO, "The address or descriptor to send the newly generated bitcoin to."},
@@ -309,8 +315,8 @@ static UniValue generateblock(const JSONRPCRequest& request)
             "\nGenerate a block to myaddress, with txs rawtx and mempool_txid\n"
             + HelpExampleCli("generateblock", R"("myaddress" '["rawtx", "mempool_txid"]')")
         },
-    }.Check(request);
-
+        [&](const RPCHelpMan& self, const JSONRPCRequest& request) -> UniValue
+{
     const auto address_or_descriptor = request.params[0].get_str();
     CScript coinbase_script;
     std::string error;
@@ -390,11 +396,13 @@ static UniValue generateblock(const JSONRPCRequest& request)
     UniValue obj(UniValue::VOBJ);
     obj.pushKV("hash", block_hash.GetHex());
     return obj;
+},
+    };
 }
 
-static UniValue getmininginfo(const JSONRPCRequest& request)
+static RPCHelpMan getmininginfo()
 {
-            RPCHelpMan{"getmininginfo",
+    return RPCHelpMan{"getmininginfo",
                 "\nReturns a json object containing mining-related information.",
                 {},
                 RPCResult{
@@ -413,8 +421,8 @@ static UniValue getmininginfo(const JSONRPCRequest& request)
                     HelpExampleCli("getmininginfo", "")
             + HelpExampleRpc("getmininginfo", "")
                 },
-            }.Check(request);
-
+        [&](const RPCHelpMan& self, const JSONRPCRequest& request) -> UniValue
+{
     LOCK(cs_main);
     const CTxMemPool& mempool = EnsureMemPool(request.context);
 
@@ -423,18 +431,20 @@ static UniValue getmininginfo(const JSONRPCRequest& request)
     if (BlockAssembler::m_last_block_weight) obj.pushKV("currentblockweight", *BlockAssembler::m_last_block_weight);
     if (BlockAssembler::m_last_block_num_txs) obj.pushKV("currentblocktx", *BlockAssembler::m_last_block_num_txs);
     obj.pushKV("difficulty",       (double)GetDifficulty(::ChainActive().Tip()));
-    obj.pushKV("networkhashps",    getnetworkhashps(request));
+    obj.pushKV("networkhashps",    getnetworkhashps().HandleRequest(request));
     obj.pushKV("pooledtx",         (uint64_t)mempool.size());
     obj.pushKV("chain",            Params().NetworkIDString());
     obj.pushKV("warnings",         GetWarnings(false).original);
     return obj;
+},
+    };
 }
 
 
 // NOTE: Unlike wallet RPC (which use BTC values), mining RPCs follow GBT (BIP 22) in using satoshi amounts
-static UniValue prioritisetransaction(const JSONRPCRequest& request)
+static RPCHelpMan prioritisetransaction()
 {
-            RPCHelpMan{"prioritisetransaction",
+    return RPCHelpMan{"prioritisetransaction",
                 "Accepts the transaction into mined blocks at a higher (or lower) priority\n",
                 {
                     {"txid", RPCArg::Type::STR_HEX, RPCArg::Optional::NO, "The transaction id."},
@@ -451,8 +461,8 @@ static UniValue prioritisetransaction(const JSONRPCRequest& request)
                     HelpExampleCli("prioritisetransaction", "\"txid\" 0.0 10000")
             + HelpExampleRpc("prioritisetransaction", "\"txid\", 0.0, 10000")
                 },
-            }.Check(request);
-
+        [&](const RPCHelpMan& self, const JSONRPCRequest& request) -> UniValue
+{
     LOCK(cs_main);
 
     uint256 hash(ParseHashV(request.params[0], "txid"));
@@ -464,6 +474,8 @@ static UniValue prioritisetransaction(const JSONRPCRequest& request)
 
     EnsureMemPool(request.context).PrioritiseTransaction(hash, nAmount);
     return true;
+},
+    };
 }
 
 
@@ -495,9 +507,9 @@ static std::string gbt_vb_name(const Consensus::DeploymentPos pos) {
     return s;
 }
 
-static UniValue getblocktemplate(const JSONRPCRequest& request)
+static RPCHelpMan getblocktemplate()
 {
-            RPCHelpMan{"getblocktemplate",
+    return RPCHelpMan{"getblocktemplate",
                 "\nIf the request parameters include a 'mode' key, that is used to explicitly select between the default 'template' request or a 'proposal'.\n"
                 "It returns data needed to construct a block to work on.\n"
                 "For full specification, see BIPs 22, 23, 9, and 145:\n"
@@ -578,8 +590,8 @@ static UniValue getblocktemplate(const JSONRPCRequest& request)
                     HelpExampleCli("getblocktemplate", "'{\"rules\": [\"segwit\"]}'")
             + HelpExampleRpc("getblocktemplate", "{\"rules\": [\"segwit\"]}")
                 },
-            }.Check(request);
-
+        [&](const RPCHelpMan& self, const JSONRPCRequest& request) -> UniValue
+{
     LOCK(cs_main);
 
     std::string strMode = "template";
@@ -887,6 +899,8 @@ static UniValue getblocktemplate(const JSONRPCRequest& request)
     }
 
     return result;
+},
+    };
 }
 
 class submitblock_StateCatcher final : public CValidationInterface
@@ -907,10 +921,10 @@ protected:
     }
 };
 
-static UniValue submitblock(const JSONRPCRequest& request)
+static RPCHelpMan submitblock()
 {
     // We allow 2 arguments for compliance with BIP22. Argument 2 is ignored.
-            RPCHelpMan{"submitblock",
+    return RPCHelpMan{"submitblock",
                 "\nAttempts to submit new block to network.\n"
                 "See https://en.bitcoin.it/wiki/BIP_0022 for full specification.\n",
                 {
@@ -922,8 +936,8 @@ static UniValue submitblock(const JSONRPCRequest& request)
                     HelpExampleCli("submitblock", "\"mydata\"")
             + HelpExampleRpc("submitblock", "\"mydata\"")
                 },
-            }.Check(request);
-
+        [&](const RPCHelpMan& self, const JSONRPCRequest& request) -> UniValue
+{
     std::shared_ptr<CBlock> blockptr = std::make_shared<CBlock>();
     CBlock& block = *blockptr;
     if (!DecodeHexBlk(block, request.params[0].get_str())) {
@@ -968,11 +982,13 @@ static UniValue submitblock(const JSONRPCRequest& request)
         return "inconclusive";
     }
     return BIP22ValidationResult(sc->state);
+},
+    };
 }
 
-static UniValue submitheader(const JSONRPCRequest& request)
+static RPCHelpMan submitheader()
 {
-            RPCHelpMan{"submitheader",
+    return RPCHelpMan{"submitheader",
                 "\nDecode the given hexdata as a header and submit it as a candidate chain tip if valid."
                 "\nThrows when the header is invalid.\n",
                 {
@@ -984,8 +1000,8 @@ static UniValue submitheader(const JSONRPCRequest& request)
                     HelpExampleCli("submitheader", "\"aabbcc\"") +
                     HelpExampleRpc("submitheader", "\"aabbcc\"")
                 },
-            }.Check(request);
-
+        [&](const RPCHelpMan& self, const JSONRPCRequest& request) -> UniValue
+{
     CBlockHeader h;
     if (!DecodeHexBlockHeader(h, request.params[0].get_str())) {
         throw JSONRPCError(RPC_DESERIALIZATION_ERROR, "Block header decode failed");
@@ -1004,11 +1020,13 @@ static UniValue submitheader(const JSONRPCRequest& request)
         throw JSONRPCError(RPC_VERIFY_ERROR, state.ToString());
     }
     throw JSONRPCError(RPC_VERIFY_ERROR, state.GetRejectReason());
+},
+    };
 }
 
-static UniValue estimatesmartfee(const JSONRPCRequest& request)
+static RPCHelpMan estimatesmartfee()
 {
-            RPCHelpMan{"estimatesmartfee",
+    return RPCHelpMan{"estimatesmartfee",
                 "\nEstimates the approximate fee per kilobyte needed for a transaction to begin\n"
                 "confirmation within conf_target blocks if possible and return the number of blocks\n"
                 "for which the estimate is valid. Uses virtual transaction size as defined\n"
@@ -1042,8 +1060,8 @@ static UniValue estimatesmartfee(const JSONRPCRequest& request)
                 RPCExamples{
                     HelpExampleCli("estimatesmartfee", "6")
                 },
-            }.Check(request);
-
+        [&](const RPCHelpMan& self, const JSONRPCRequest& request) -> UniValue
+{
     RPCTypeCheck(request.params, {UniValue::VNUM, UniValue::VSTR});
     RPCTypeCheckArgument(request.params[0], UniValue::VNUM);
     unsigned int max_target = ::feeEstimator.HighestTargetTracked(FeeEstimateHorizon::LONG_HALFLIFE);
@@ -1069,11 +1087,13 @@ static UniValue estimatesmartfee(const JSONRPCRequest& request)
     }
     result.pushKV("blocks", feeCalc.returnedTarget);
     return result;
+},
+    };
 }
 
-static UniValue estimaterawfee(const JSONRPCRequest& request)
+static RPCHelpMan estimaterawfee()
 {
-            RPCHelpMan{"estimaterawfee",
+    return RPCHelpMan{"estimaterawfee",
                 "\nWARNING: This interface is unstable and may disappear or change!\n"
                 "\nWARNING: This is an advanced API call that is tightly coupled to the specific\n"
                 "         implementation of fee estimation. The parameters it can be called with\n"
@@ -1125,8 +1145,8 @@ static UniValue estimaterawfee(const JSONRPCRequest& request)
                 RPCExamples{
                     HelpExampleCli("estimaterawfee", "6 0.9")
                 },
-            }.Check(request);
-
+        [&](const RPCHelpMan& self, const JSONRPCRequest& request) -> UniValue
+{
     RPCTypeCheck(request.params, {UniValue::VNUM, UniValue::VNUM}, true);
     RPCTypeCheckArgument(request.params[0], UniValue::VNUM);
     unsigned int max_target = ::feeEstimator.HighestTargetTracked(FeeEstimateHorizon::LONG_HALFLIFE);
@@ -1185,6 +1205,8 @@ static UniValue estimaterawfee(const JSONRPCRequest& request)
         result.pushKV(StringForFeeEstimateHorizon(horizon), horizon_result);
     }
     return result;
+},
+    };
 }
 
 void RegisterMiningRPCCommands(CRPCTable &t)
diff --git a/src/rpc/server.cpp b/src/rpc/server.cpp
index 9c8e7fe04a..f32d9abac6 100644
--- a/src/rpc/server.cpp
+++ b/src/rpc/server.cpp
@@ -261,13 +261,11 @@ CRPCTable::CRPCTable()
     }
 }
 
-bool CRPCTable::appendCommand(const std::string& name, const CRPCCommand* pcmd)
+void CRPCTable::appendCommand(const std::string& name, const CRPCCommand* pcmd)
 {
-    if (IsRPCRunning())
-        return false;
+    CHECK_NONFATAL(!IsRPCRunning()); // Only add commands before rpc is running
 
     mapCommands[name].push_back(pcmd);
-    return true;
 }
 
 bool CRPCTable::removeCommand(const std::string& name, const CRPCCommand* pcmd)
diff --git a/src/rpc/server.h b/src/rpc/server.h
index 6da3e94ea2..b2358ac5b2 100644
--- a/src/rpc/server.h
+++ b/src/rpc/server.h
@@ -160,7 +160,7 @@ public:
     /**
      * Appends a CRPCCommand to the dispatch table.
      *
-     * Returns false if RPC server is already running (dump concurrency protection).
+     * Precondition: RPC server is not running
      *
      * Commands with different method names but the same unique_id will
      * be considered aliases, and only the first registered method name will
@@ -169,7 +169,7 @@ public:
      * between calls based on method name, and aliased commands can also
      * register different names, types, and numbers of parameters.
      */
-    bool appendCommand(const std::string& name, const CRPCCommand* pcmd);
+    void appendCommand(const std::string& name, const CRPCCommand* pcmd);
     bool removeCommand(const std::string& name, const CRPCCommand* pcmd);
 };