[rpc] Deprecate getpeerinfo addnode field

This field is now redundant since the connection type field will indicate
MANUAL for addnode connections.

src/rpc/net.cpp

@@ -112,7 +112,8 @@ static UniValue getpeerinfo(const JSONRPCRequest& request)
                             {RPCResult::Type::NUM, "version", "The peer version, such as 70001"},
                             {RPCResult::Type::STR, "subver", "The string version"},
                             {RPCResult::Type::BOOL, "inbound", "Inbound (true) or Outbound (false)"},
-                            {RPCResult::Type::BOOL, "addnode", "Whether connection was due to addnode/-connect or if it was an automatic/inbound connection"},
+                            {RPCResult::Type::BOOL, "addnode", "Whether connection was due to addnode/-connect or if it was an automatic/inbound connection\n"
+                                                               "(DEPRECATED, returned only if the config option -deprecatedrpc=getpeerinfo_addnode is passed)"},
                             {RPCResult::Type::STR, "connection_type", "Type of connection: \n" + Join(CONNECTION_TYPE_DOC, ",\n") + "."},
                             {RPCResult::Type::NUM, "startingheight", "The starting height (block) of the peer"},
                             {RPCResult::Type::NUM, "banscore", "The ban score (DEPRECATED, returned only if config option -deprecatedrpc=banscore is passed)"},
@@ -193,7 +194,10 @@ static UniValue getpeerinfo(const JSONRPCRequest& request)
         // their ver message.
         obj.pushKV("subver", stats.cleanSubVer);
         obj.pushKV("inbound", stats.fInbound);
-        obj.pushKV("addnode", stats.m_manual_connection);
+        if (IsDeprecatedRPCEnabled("getpeerinfo_addnode")) {
+            // addnode is deprecated in v0.21 for removal in v0.22
+            obj.pushKV("addnode", stats.m_manual_connection);
+        }
         obj.pushKV("startingheight", stats.nStartingHeight);
         if (fStateStats) {
             if (IsDeprecatedRPCEnabled("banscore")) {

test/functional/rpc_getpeerinfo_deprecation.py

@@ -5,6 +5,7 @@
 """Test deprecation of getpeerinfo RPC fields."""
 
 from test_framework.test_framework import BitcoinTestFramework
+from test_framework.util import connect_nodes
 
 
 class GetpeerinfoDeprecationTest(BitcoinTestFramework):
@@ -14,6 +15,7 @@ class GetpeerinfoDeprecationTest(BitcoinTestFramework):
 
     def run_test(self):
         self.test_banscore_deprecation()
+        self.test_addnode_deprecation()
 
     def test_banscore_deprecation(self):
         self.log.info("Test getpeerinfo by default no longer returns a banscore field")
@@ -22,5 +24,16 @@ class GetpeerinfoDeprecationTest(BitcoinTestFramework):
         self.log.info("Test getpeerinfo returns banscore with -deprecatedrpc=banscore")
         assert "banscore" in self.nodes[1].getpeerinfo()[0].keys()
 
+    def test_addnode_deprecation(self):
+        self.restart_node(1, ["-deprecatedrpc=getpeerinfo_addnode"])
+        connect_nodes(self.nodes[0], 1)
+
+        self.log.info("Test getpeerinfo by default no longer returns an addnode field")
+        assert "addnode" not in self.nodes[0].getpeerinfo()[0].keys()
+
+        self.log.info("Test getpeerinfo returns addnode with -deprecatedrpc=addnode")
+        assert "addnode" in self.nodes[1].getpeerinfo()[0].keys()
+
+
 if __name__ == "__main__":
     GetpeerinfoDeprecationTest().main()