Merge #18740: Remove g_rpc_node global

b3f7f375efb9a9ca9a7a4f2caf41fe3df2262520 refactor: Remove g_rpc_node global (Russell Yanofsky)
ccb5059ee89f6e8dc31ba5b82830b384890bb65e scripted-diff: Remove g_rpc_node references (Russell Yanofsky)
6fca33b2edc09ed62dab2323c780b31585de1750 refactor: Pass NodeContext to RPC and REST methods through util::Ref (Russell Yanofsky)
691c817b340d10e806dc3b1834d2a8fcc5e681fd Add util::Ref class as temporary alternative for c++17 std::any (Russell Yanofsky)

Pull request description:

  This PR removes the `g_rpc_node` global, to get same benefits we see removing other globals and make RPC code more testable, modular, and reusable.

  This uses a hybrid of the approaches suggested in #17548. Instead of using `std::any`, which isn't available in c++11, or `void*`, which isn't type safe, it uses a small new `util::Ref` helper class, which acts like a simplified `std::any` that only holds references, not values.

  Motivation for writing this was to provide an simpler alternative to #18647 by Harris Brakmić (brakmic) which avoids some shortcomings of that PR (https://github.com/bitcoin/bitcoin/pull/18647#issuecomment-617878826)

ACKs for top commit:
  MarcoFalke:
    re-ACK b3f7f375ef, only change is adding back const and more tests 🚾
  ajtowns:
    ACK b3f7f375efb9a9ca9a7a4f2caf41fe3df2262520

Tree-SHA512: 56292268a001bdbe34d641db1180c215351503966ff451e55cc96c9137f1d262225d7d7733de9c9da7ce7d7a4b34213a98c2476266b58c89dbbb0f3cb5aa5d70

7 files changed, 114 insertions, 85 deletions

diff --git a/src/rpc/blockchain.cpp b/src/rpc/blockchain.cpp
index 2c984603ff..3c5fd565e3 100644
--- a/src/rpc/blockchain.cpp
+++ b/src/rpc/blockchain.cpp
@@ -29,6 +29,7 @@
 #include <txdb.h>
 #include <txmempool.h>
 #include <undo.h>
+#include <util/ref.h>
 #include <util/strencodings.h>
 #include <util/system.h>
 #include <validation.h>
@@ -53,13 +54,21 @@ static Mutex cs_blockchange;
 static std::condition_variable cond_blockchange;
 static CUpdatedBlock latestblock;
 
-CTxMemPool& EnsureMemPool()
+NodeContext& EnsureNodeContext(const util::Ref& context)
 {
-    CHECK_NONFATAL(g_rpc_node);
-    if (!g_rpc_node->mempool) {
+    if (!context.Has<NodeContext>()) {
+        throw JSONRPCError(RPC_INTERNAL_ERROR, "Node context not found");
+    }
+    return context.Get<NodeContext>();
+}
+
+CTxMemPool& EnsureMemPool(const util::Ref& context)
+{
+    NodeContext& node = EnsureNodeContext(context);
+    if (!node.mempool) {
         throw JSONRPCError(RPC_CLIENT_MEMPOOL_DISABLED, "Mempool disabled or instance not found");
     }
-    return *g_rpc_node->mempool;
+    return *node.mempool;
 }
 
 /* Calculate the difficulty for a given block index.
@@ -519,7 +528,7 @@ static UniValue getrawmempool(const JSONRPCRequest& request)
     if (!request.params[0].isNull())
         fVerbose = request.params[0].get_bool();
 
-    return MempoolToJSON(EnsureMemPool(), fVerbose);
+    return MempoolToJSON(EnsureMemPool(request.context), fVerbose);
 }
 
 static UniValue getmempoolancestors(const JSONRPCRequest& request)
@@ -549,7 +558,7 @@ static UniValue getmempoolancestors(const JSONRPCRequest& request)
 
     uint256 hash = ParseHashV(request.params[0], "parameter 1");
 
-    const CTxMemPool& mempool = EnsureMemPool();
+    const CTxMemPool& mempool = EnsureMemPool(request.context);
     LOCK(mempool.cs);
 
     CTxMemPool::txiter it = mempool.mapTx.find(hash);
@@ -612,7 +621,7 @@ static UniValue getmempooldescendants(const JSONRPCRequest& request)
 
     uint256 hash = ParseHashV(request.params[0], "parameter 1");
 
-    const CTxMemPool& mempool = EnsureMemPool();
+    const CTxMemPool& mempool = EnsureMemPool(request.context);
     LOCK(mempool.cs);
 
     CTxMemPool::txiter it = mempool.mapTx.find(hash);
@@ -662,7 +671,7 @@ static UniValue getmempoolentry(const JSONRPCRequest& request)
 
     uint256 hash = ParseHashV(request.params[0], "parameter 1");
 
-    const CTxMemPool& mempool = EnsureMemPool();
+    const CTxMemPool& mempool = EnsureMemPool(request.context);
     LOCK(mempool.cs);
 
     CTxMemPool::txiter it = mempool.mapTx.find(hash);
@@ -1045,7 +1054,7 @@ UniValue gettxout(const JSONRPCRequest& request)
     CCoinsViewCache* coins_view = &::ChainstateActive().CoinsTip();
 
     if (fMempool) {
-        const CTxMemPool& mempool = EnsureMemPool();
+        const CTxMemPool& mempool = EnsureMemPool(request.context);
         LOCK(mempool.cs);
         CCoinsViewMemPool view(coins_view, mempool);
         if (!view.GetCoin(out, coin) || mempool.isSpent(out)) {
@@ -1415,7 +1424,7 @@ static UniValue getmempoolinfo(const JSONRPCRequest& request)
                 },
             }.Check(request);
 
-    return MempoolInfoToJSON(EnsureMemPool());
+    return MempoolInfoToJSON(EnsureMemPool(request.context));
 }
 
 static UniValue preciousblock(const JSONRPCRequest& request)
@@ -1934,7 +1943,7 @@ static UniValue savemempool(const JSONRPCRequest& request)
                 },
             }.Check(request);
 
-    const CTxMemPool& mempool = EnsureMemPool();
+    const CTxMemPool& mempool = EnsureMemPool(request.context);
 
     if (!mempool.IsLoaded()) {
         throw JSONRPCError(RPC_MISC_ERROR, "The mempool was not loaded yet");
@@ -2385,5 +2394,3 @@ static const CRPCCommand commands[] =
     for (unsigned int vcidx = 0; vcidx < ARRAYLEN(commands); vcidx++)
         t.appendCommand(commands[vcidx].name, &commands[vcidx]);
 }
-
-NodeContext* g_rpc_node = nullptr;
diff --git a/src/rpc/blockchain.h b/src/rpc/blockchain.h
index 54165af707..453d0bc650 100644
--- a/src/rpc/blockchain.h
+++ b/src/rpc/blockchain.h
@@ -18,6 +18,9 @@ class CBlockIndex;
 class CTxMemPool;
 class UniValue;
 struct NodeContext;
+namespace util {
+class Ref;
+} // namespace util
 
 static constexpr int NUM_GETBLOCKSTATS_PERCENTILES = 5;
 
@@ -47,11 +50,7 @@ UniValue blockheaderToJSON(const CBlockIndex* tip, const CBlockIndex* blockindex
 /** Used by getblockstats to get feerates at different percentiles by weight  */
 void CalculatePercentilesByWeight(CAmount result[NUM_GETBLOCKSTATS_PERCENTILES], std::vector<std::pair<CAmount, int64_t>>& scores, int64_t total_weight);
 
-//! Pointer to node state that needs to be declared as a global to be accessible
-//! RPC methods. Due to limitations of the RPC framework, there's currently no
-//! direct way to pass in state to RPC methods without globals.
-extern NodeContext* g_rpc_node;
-
-CTxMemPool& EnsureMemPool();
+NodeContext& EnsureNodeContext(const util::Ref& context);
+CTxMemPool& EnsureMemPool(const util::Ref& context);
 
 #endif
diff --git a/src/rpc/mining.cpp b/src/rpc/mining.cpp
index 59ab80bcd5..bcaed1ef88 100644
--- a/src/rpc/mining.cpp
+++ b/src/rpc/mining.cpp
@@ -227,7 +227,7 @@ static UniValue generatetodescriptor(const JSONRPCRequest& request)
         throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, error);
     }
 
-    const CTxMemPool& mempool = EnsureMemPool();
+    const CTxMemPool& mempool = EnsureMemPool(request.context);
 
     return generateBlocks(mempool, coinbase_script, num_blocks, max_tries);
 }
@@ -265,7 +265,7 @@ static UniValue generatetoaddress(const JSONRPCRequest& request)
         throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Error: Invalid address");
     }
 
-    const CTxMemPool& mempool = EnsureMemPool();
+    const CTxMemPool& mempool = EnsureMemPool(request.context);
 
     CScript coinbase_script = GetScriptForDestination(destination);
 
@@ -311,7 +311,7 @@ static UniValue generateblock(const JSONRPCRequest& request)
         coinbase_script = GetScriptForDestination(destination);
     }
 
-    const CTxMemPool& mempool = EnsureMemPool();
+    const CTxMemPool& mempool = EnsureMemPool(request.context);
 
     std::vector<CTransactionRef> txs;
     const auto raw_txs_or_txids = request.params[1].get_array();
@@ -403,7 +403,7 @@ static UniValue getmininginfo(const JSONRPCRequest& request)
             }.Check(request);
 
     LOCK(cs_main);
-    const CTxMemPool& mempool = EnsureMemPool();
+    const CTxMemPool& mempool = EnsureMemPool(request.context);
 
     UniValue obj(UniValue::VOBJ);
     obj.pushKV("blocks",           (int)::ChainActive().Height());
@@ -449,7 +449,7 @@ static UniValue prioritisetransaction(const JSONRPCRequest& request)
         throw JSONRPCError(RPC_INVALID_PARAMETER, "Priority is no longer supported, dummy argument to prioritisetransaction must be 0.");
     }
 
-    EnsureMemPool().PrioritiseTransaction(hash, nAmount);
+    EnsureMemPool(request.context).PrioritiseTransaction(hash, nAmount);
     return true;
 }
 
@@ -635,17 +635,18 @@ static UniValue getblocktemplate(const JSONRPCRequest& request)
     if (strMode != "template")
         throw JSONRPCError(RPC_INVALID_PARAMETER, "Invalid mode");
 
-    if(!g_rpc_node->connman)
+    NodeContext& node = EnsureNodeContext(request.context);
+    if(!node.connman)
         throw JSONRPCError(RPC_CLIENT_P2P_DISABLED, "Error: Peer-to-peer functionality missing or disabled");
 
-    if (g_rpc_node->connman->GetNodeCount(CConnman::CONNECTIONS_ALL) == 0)
+    if (node.connman->GetNodeCount(CConnman::CONNECTIONS_ALL) == 0)
         throw JSONRPCError(RPC_CLIENT_NOT_CONNECTED, PACKAGE_NAME " is not connected!");
 
     if (::ChainstateActive().IsInitialBlockDownload())
         throw JSONRPCError(RPC_CLIENT_IN_INITIAL_DOWNLOAD, PACKAGE_NAME " is in initial sync and waiting for blocks...");
 
     static unsigned int nTransactionsUpdatedLast;
-    const CTxMemPool& mempool = EnsureMemPool();
+    const CTxMemPool& mempool = EnsureMemPool(request.context);
 
     if (!lpval.isNull())
     {
diff --git a/src/rpc/misc.cpp b/src/rpc/misc.cpp
index f3c5fed858..ce98a7c937 100644
--- a/src/rpc/misc.cpp
+++ b/src/rpc/misc.cpp
@@ -15,6 +15,7 @@
 #include <script/descriptor.h>
 #include <util/check.h>
 #include <util/message.h> // For MessageSign(), MessageVerify()
+#include <util/ref.h>
 #include <util/strencodings.h>
 #include <util/system.h>
 
@@ -366,8 +367,8 @@ static UniValue setmocktime(const JSONRPCRequest& request)
     RPCTypeCheck(request.params, {UniValue::VNUM});
     int64_t time = request.params[0].get_int64();
     SetMockTime(time);
-    if (g_rpc_node) {
-        for (const auto& chain_client : g_rpc_node->chain_clients) {
+    if (request.context.Has<NodeContext>()) {
+        for (const auto& chain_client : request.context.Get<NodeContext>().chain_clients) {
             chain_client->setMockTime(time);
         }
     }
@@ -398,9 +399,10 @@ static UniValue mockscheduler(const JSONRPCRequest& request)
     }
 
     // protect against null pointer dereference
-    CHECK_NONFATAL(g_rpc_node);
-    CHECK_NONFATAL(g_rpc_node->scheduler);
-    g_rpc_node->scheduler->MockForward(std::chrono::seconds(delta_seconds));
+    CHECK_NONFATAL(request.context.Has<NodeContext>());
+    NodeContext& node = request.context.Get<NodeContext>();
+    CHECK_NONFATAL(node.scheduler);
+    node.scheduler->MockForward(std::chrono::seconds(delta_seconds));
 
     return NullUniValue;
 }
diff --git a/src/rpc/net.cpp b/src/rpc/net.cpp
index d6d15f8b56..e29aa03695 100644
--- a/src/rpc/net.cpp
+++ b/src/rpc/net.cpp
@@ -42,10 +42,11 @@ static UniValue getconnectioncount(const JSONRPCRequest& request)
                 },
             }.Check(request);
 
-    if(!g_rpc_node->connman)
+    NodeContext& node = EnsureNodeContext(request.context);
+    if(!node.connman)
         throw JSONRPCError(RPC_CLIENT_P2P_DISABLED, "Error: Peer-to-peer functionality missing or disabled");
 
-    return (int)g_rpc_node->connman->GetNodeCount(CConnman::CONNECTIONS_ALL);
+    return (int)node.connman->GetNodeCount(CConnman::CONNECTIONS_ALL);
 }
 
 static UniValue ping(const JSONRPCRequest& request)
@@ -62,11 +63,12 @@ static UniValue ping(const JSONRPCRequest& request)
                 },
             }.Check(request);
 
-    if(!g_rpc_node->connman)
+    NodeContext& node = EnsureNodeContext(request.context);
+    if(!node.connman)
         throw JSONRPCError(RPC_CLIENT_P2P_DISABLED, "Error: Peer-to-peer functionality missing or disabled");
 
     // Request that each node send a ping during next message processing pass
-    g_rpc_node->connman->ForEachNode([](CNode* pnode) {
+    node.connman->ForEachNode([](CNode* pnode) {
         pnode->fPingQueued = true;
     });
     return NullUniValue;
@@ -139,11 +141,12 @@ static UniValue getpeerinfo(const JSONRPCRequest& request)
                 },
             }.Check(request);
 
-    if(!g_rpc_node->connman)
+    NodeContext& node = EnsureNodeContext(request.context);
+    if(!node.connman)
         throw JSONRPCError(RPC_CLIENT_P2P_DISABLED, "Error: Peer-to-peer functionality missing or disabled");
 
     std::vector<CNodeStats> vstats;
-    g_rpc_node->connman->GetNodeStats(vstats);
+    node.connman->GetNodeStats(vstats);
 
     UniValue ret(UniValue::VARR);
 
@@ -248,7 +251,8 @@ static UniValue addnode(const JSONRPCRequest& request)
                 },
             }.ToString());
 
-    if(!g_rpc_node->connman)
+    NodeContext& node = EnsureNodeContext(request.context);
+    if(!node.connman)
         throw JSONRPCError(RPC_CLIENT_P2P_DISABLED, "Error: Peer-to-peer functionality missing or disabled");
 
     std::string strNode = request.params[0].get_str();
@@ -256,18 +260,18 @@ static UniValue addnode(const JSONRPCRequest& request)
     if (strCommand == "onetry")
     {
         CAddress addr;
-        g_rpc_node->connman->OpenNetworkConnection(addr, false, nullptr, strNode.c_str(), false, false, true);
+        node.connman->OpenNetworkConnection(addr, false, nullptr, strNode.c_str(), false, false, true);
         return NullUniValue;
     }
 
     if (strCommand == "add")
     {
-        if(!g_rpc_node->connman->AddNode(strNode))
+        if(!node.connman->AddNode(strNode))
             throw JSONRPCError(RPC_CLIENT_NODE_ALREADY_ADDED, "Error: Node already added");
     }
     else if(strCommand == "remove")
     {
-        if(!g_rpc_node->connman->RemoveAddedNode(strNode))
+        if(!node.connman->RemoveAddedNode(strNode))
             throw JSONRPCError(RPC_CLIENT_NODE_NOT_ADDED, "Error: Node has not been added.");
     }
 
@@ -293,7 +297,8 @@ static UniValue disconnectnode(const JSONRPCRequest& request)
                 },
             }.Check(request);
 
-    if(!g_rpc_node->connman)
+    NodeContext& node = EnsureNodeContext(request.context);
+    if(!node.connman)
         throw JSONRPCError(RPC_CLIENT_P2P_DISABLED, "Error: Peer-to-peer functionality missing or disabled");
 
     bool success;
@@ -302,11 +307,11 @@ static UniValue disconnectnode(const JSONRPCRequest& request)
 
     if (!address_arg.isNull() && id_arg.isNull()) {
         /* handle disconnect-by-address */
-        success = g_rpc_node->connman->DisconnectNode(address_arg.get_str());
+        success = node.connman->DisconnectNode(address_arg.get_str());
     } else if (!id_arg.isNull() && (address_arg.isNull() || (address_arg.isStr() && address_arg.get_str().empty()))) {
         /* handle disconnect-by-id */
         NodeId nodeid = (NodeId) id_arg.get_int64();
-        success = g_rpc_node->connman->DisconnectNode(nodeid);
+        success = node.connman->DisconnectNode(nodeid);
     } else {
         throw JSONRPCError(RPC_INVALID_PARAMS, "Only one of address and nodeid should be provided.");
     }
@@ -350,10 +355,11 @@ static UniValue getaddednodeinfo(const JSONRPCRequest& request)
                 },
             }.Check(request);
 
-    if(!g_rpc_node->connman)
+    NodeContext& node = EnsureNodeContext(request.context);
+    if(!node.connman)
         throw JSONRPCError(RPC_CLIENT_P2P_DISABLED, "Error: Peer-to-peer functionality missing or disabled");
 
-    std::vector<AddedNodeInfo> vInfo = g_rpc_node->connman->GetAddedNodeInfo();
+    std::vector<AddedNodeInfo> vInfo = node.connman->GetAddedNodeInfo();
 
     if (!request.params[0].isNull()) {
         bool found = false;
@@ -417,21 +423,22 @@ static UniValue getnettotals(const JSONRPCRequest& request)
             + HelpExampleRpc("getnettotals", "")
                 },
             }.Check(request);
-    if(!g_rpc_node->connman)
+    NodeContext& node = EnsureNodeContext(request.context);
+    if(!node.connman)
         throw JSONRPCError(RPC_CLIENT_P2P_DISABLED, "Error: Peer-to-peer functionality missing or disabled");
 
     UniValue obj(UniValue::VOBJ);
-    obj.pushKV("totalbytesrecv", g_rpc_node->connman->GetTotalBytesRecv());
-    obj.pushKV("totalbytessent", g_rpc_node->connman->GetTotalBytesSent());
+    obj.pushKV("totalbytesrecv", node.connman->GetTotalBytesRecv());
+    obj.pushKV("totalbytessent", node.connman->GetTotalBytesSent());
     obj.pushKV("timemillis", GetTimeMillis());
 
     UniValue outboundLimit(UniValue::VOBJ);
-    outboundLimit.pushKV("timeframe", g_rpc_node->connman->GetMaxOutboundTimeframe());
-    outboundLimit.pushKV("target", g_rpc_node->connman->GetMaxOutboundTarget());
-    outboundLimit.pushKV("target_reached", g_rpc_node->connman->OutboundTargetReached(false));
-    outboundLimit.pushKV("serve_historical_blocks", !g_rpc_node->connman->OutboundTargetReached(true));
-    outboundLimit.pushKV("bytes_left_in_cycle", g_rpc_node->connman->GetOutboundTargetBytesLeft());
-    outboundLimit.pushKV("time_left_in_cycle", g_rpc_node->connman->GetMaxOutboundTimeLeftInCycle());
+    outboundLimit.pushKV("timeframe", node.connman->GetMaxOutboundTimeframe());
+    outboundLimit.pushKV("target", node.connman->GetMaxOutboundTarget());
+    outboundLimit.pushKV("target_reached", node.connman->OutboundTargetReached(false));
+    outboundLimit.pushKV("serve_historical_blocks", !node.connman->OutboundTargetReached(true));
+    outboundLimit.pushKV("bytes_left_in_cycle", node.connman->GetOutboundTargetBytesLeft());
+    outboundLimit.pushKV("time_left_in_cycle", node.connman->GetMaxOutboundTimeLeftInCycle());
     obj.pushKV("uploadtarget", outboundLimit);
     return obj;
 }
@@ -513,16 +520,17 @@ static UniValue getnetworkinfo(const JSONRPCRequest& request)
     obj.pushKV("version",       CLIENT_VERSION);
     obj.pushKV("subversion",    strSubVersion);
     obj.pushKV("protocolversion",PROTOCOL_VERSION);
-    if (g_rpc_node->connman) {
-        ServiceFlags services = g_rpc_node->connman->GetLocalServices();
+    NodeContext& node = EnsureNodeContext(request.context);
+    if (node.connman) {
+        ServiceFlags services = node.connman->GetLocalServices();
         obj.pushKV("localservices", strprintf("%016x", services));
         obj.pushKV("localservicesnames", GetServicesNames(services));
     }
     obj.pushKV("localrelay", g_relay_txes);
     obj.pushKV("timeoffset",    GetTimeOffset());
-    if (g_rpc_node->connman) {
-        obj.pushKV("networkactive", g_rpc_node->connman->GetNetworkActive());
-        obj.pushKV("connections",   (int)g_rpc_node->connman->GetNodeCount(CConnman::CONNECTIONS_ALL));
+    if (node.connman) {
+        obj.pushKV("networkactive", node.connman->GetNetworkActive());
+        obj.pushKV("connections",   (int)node.connman->GetNodeCount(CConnman::CONNECTIONS_ALL));
     }
     obj.pushKV("networks",      GetNetworksInfo());
     obj.pushKV("relayfee",      ValueFromAmount(::minRelayTxFee.GetFeePerK()));
@@ -567,7 +575,8 @@ static UniValue setban(const JSONRPCRequest& request)
     if (request.fHelp || !help.IsValidNumArgs(request.params.size()) || (strCommand != "add" && strCommand != "remove")) {
         throw std::runtime_error(help.ToString());
     }
-    if (!g_rpc_node->banman) {
+    NodeContext& node = EnsureNodeContext(request.context);
+    if (!node.banman) {
         throw JSONRPCError(RPC_DATABASE_ERROR, "Error: Ban database not loaded");
     }
 
@@ -591,7 +600,7 @@ static UniValue setban(const JSONRPCRequest& request)
 
     if (strCommand == "add")
     {
-        if (isSubnet ? g_rpc_node->banman->IsBanned(subNet) : g_rpc_node->banman->IsBanned(netAddr)) {
+        if (isSubnet ? node.banman->IsBanned(subNet) : node.banman->IsBanned(netAddr)) {
             throw JSONRPCError(RPC_CLIENT_NODE_ALREADY_ADDED, "Error: IP/Subnet already banned");
         }
 
@@ -604,20 +613,20 @@ static UniValue setban(const JSONRPCRequest& request)
             absolute = true;
 
         if (isSubnet) {
-            g_rpc_node->banman->Ban(subNet, BanReasonManuallyAdded, banTime, absolute);
-            if (g_rpc_node->connman) {
-                g_rpc_node->connman->DisconnectNode(subNet);
+            node.banman->Ban(subNet, BanReasonManuallyAdded, banTime, absolute);
+            if (node.connman) {
+                node.connman->DisconnectNode(subNet);
             }
         } else {
-            g_rpc_node->banman->Ban(netAddr, BanReasonManuallyAdded, banTime, absolute);
-            if (g_rpc_node->connman) {
-                g_rpc_node->connman->DisconnectNode(netAddr);
+            node.banman->Ban(netAddr, BanReasonManuallyAdded, banTime, absolute);
+            if (node.connman) {
+                node.connman->DisconnectNode(netAddr);
             }
         }
     }
     else if(strCommand == "remove")
     {
-        if (!( isSubnet ? g_rpc_node->banman->Unban(subNet) : g_rpc_node->banman->Unban(netAddr) )) {
+        if (!( isSubnet ? node.banman->Unban(subNet) : node.banman->Unban(netAddr) )) {
             throw JSONRPCError(RPC_CLIENT_INVALID_IP_OR_SUBNET, "Error: Unban failed. Requested address/subnet was not previously banned.");
         }
     }
@@ -645,12 +654,13 @@ static UniValue listbanned(const JSONRPCRequest& request)
                 },
             }.Check(request);
 
-    if(!g_rpc_node->banman) {
+    NodeContext& node = EnsureNodeContext(request.context);
+    if(!node.banman) {
         throw JSONRPCError(RPC_DATABASE_ERROR, "Error: Ban database not loaded");
     }
 
     banmap_t banMap;
-    g_rpc_node->banman->GetBanned(banMap);
+    node.banman->GetBanned(banMap);
 
     UniValue bannedAddresses(UniValue::VARR);
     for (const auto& entry : banMap)
@@ -679,11 +689,12 @@ static UniValue clearbanned(const JSONRPCRequest& request)
                             + HelpExampleRpc("clearbanned", "")
                 },
             }.Check(request);
-    if (!g_rpc_node->banman) {
+    NodeContext& node = EnsureNodeContext(request.context);
+    if (!node.banman) {
         throw JSONRPCError(RPC_DATABASE_ERROR, "Error: Ban database not loaded");
     }
 
-    g_rpc_node->banman->ClearBanned();
+    node.banman->ClearBanned();
 
     return NullUniValue;
 }
@@ -699,13 +710,14 @@ static UniValue setnetworkactive(const JSONRPCRequest& request)
                 RPCExamples{""},
             }.Check(request);
 
-    if (!g_rpc_node->connman) {
+    NodeContext& node = EnsureNodeContext(request.context);
+    if (!node.connman) {
         throw JSONRPCError(RPC_CLIENT_P2P_DISABLED, "Error: Peer-to-peer functionality missing or disabled");
     }
 
-    g_rpc_node->connman->SetNetworkActive(request.params[0].get_bool());
+    node.connman->SetNetworkActive(request.params[0].get_bool());
 
-    return g_rpc_node->connman->GetNetworkActive();
+    return node.connman->GetNetworkActive();
 }
 
 static UniValue getnodeaddresses(const JSONRPCRequest& request)
@@ -732,7 +744,8 @@ static UniValue getnodeaddresses(const JSONRPCRequest& request)
             + HelpExampleRpc("getnodeaddresses", "8")
                 },
             }.Check(request);
-    if (!g_rpc_node->connman) {
+    NodeContext& node = EnsureNodeContext(request.context);
+    if (!node.connman) {
         throw JSONRPCError(RPC_CLIENT_P2P_DISABLED, "Error: Peer-to-peer functionality missing or disabled");
     }
 
@@ -744,7 +757,7 @@ static UniValue getnodeaddresses(const JSONRPCRequest& request)
         }
     }
     // returns a shuffled list of CAddress
-    std::vector<CAddress> vAddr = g_rpc_node->connman->GetAddresses();
+    std::vector<CAddress> vAddr = node.connman->GetAddresses();
     UniValue ret(UniValue::VARR);
 
     int address_return_count = std::min<int>(count, vAddr.size());
diff --git a/src/rpc/rawtransaction.cpp b/src/rpc/rawtransaction.cpp
index 063ee1697c..e14217c307 100644
--- a/src/rpc/rawtransaction.cpp
+++ b/src/rpc/rawtransaction.cpp
@@ -653,7 +653,7 @@ static UniValue combinerawtransaction(const JSONRPCRequest& request)
     CCoinsView viewDummy;
     CCoinsViewCache view(&viewDummy);
     {
-        const CTxMemPool& mempool = EnsureMemPool();
+        const CTxMemPool& mempool = EnsureMemPool(request.context);
         LOCK(cs_main);
         LOCK(mempool.cs);
         CCoinsViewCache &viewChain = ::ChainstateActive().CoinsTip();
@@ -778,7 +778,8 @@ static UniValue signrawtransactionwithkey(const JSONRPCRequest& request)
     for (const CTxIn& txin : mtx.vin) {
         coins[txin.prevout]; // Create empty map entry keyed by prevout.
     }
-    FindCoins(*g_rpc_node, coins);
+    NodeContext& node = EnsureNodeContext(request.context);
+    FindCoins(node, coins);
 
     // Parse the prevtxs array
     ParsePrevouts(request.params[2], &keystore, coins);
@@ -837,7 +838,8 @@ static UniValue sendrawtransaction(const JSONRPCRequest& request)
 
     std::string err_string;
     AssertLockNotHeld(cs_main);
-    const TransactionError err = BroadcastTransaction(*g_rpc_node, tx, err_string, max_raw_tx_fee, /*relay*/ true, /*wait_callback*/ true);
+    NodeContext& node = EnsureNodeContext(request.context);
+    const TransactionError err = BroadcastTransaction(node, tx, err_string, max_raw_tx_fee, /*relay*/ true, /*wait_callback*/ true);
     if (TransactionError::OK != err) {
         throw JSONRPCTransactionError(err, err_string);
     }
@@ -904,7 +906,7 @@ static UniValue testmempoolaccept(const JSONRPCRequest& request)
                                              DEFAULT_MAX_RAW_TX_FEE_RATE :
                                              CFeeRate(AmountFromValue(request.params[1]));
 
-    CTxMemPool& mempool = EnsureMemPool();
+    CTxMemPool& mempool = EnsureMemPool(request.context);
     int64_t virtual_size = GetVirtualTransactionSize(*tx);
     CAmount max_raw_tx_fee = max_raw_tx_fee_rate.GetFee(virtual_size);
 
@@ -1555,7 +1557,7 @@ UniValue utxoupdatepsbt(const JSONRPCRequest& request)
     CCoinsView viewDummy;
     CCoinsViewCache view(&viewDummy);
     {
-        const CTxMemPool& mempool = EnsureMemPool();
+        const CTxMemPool& mempool = EnsureMemPool(request.context);
         LOCK2(cs_main, mempool.cs);
         CCoinsViewCache &viewChain = ::ChainstateActive().CoinsTip();
         CCoinsViewMemPool viewMempool(&viewChain, mempool);
diff --git a/src/rpc/request.h b/src/rpc/request.h
index 99eb4f9354..0a15b48de4 100644
--- a/src/rpc/request.h
+++ b/src/rpc/request.h
@@ -10,6 +10,10 @@
 
 #include <univalue.h>
 
+namespace util {
+class Ref;
+} // namespace util
+
 UniValue JSONRPCRequestObj(const std::string& strMethod, const UniValue& params, const UniValue& id);
 UniValue JSONRPCReplyObj(const UniValue& result, const UniValue& error, const UniValue& id);
 std::string JSONRPCReply(const UniValue& result, const UniValue& error, const UniValue& id);
@@ -34,8 +38,9 @@ public:
     std::string URI;
     std::string authUser;
     std::string peerAddr;
+    const util::Ref& context;
 
-    JSONRPCRequest() : id(NullUniValue), params(NullUniValue), fHelp(false) {}
+    JSONRPCRequest(const util::Ref& context) : id(NullUniValue), params(NullUniValue), fHelp(false), context(context) {}
     void parse(const UniValue& valRequest);
 };