rpc: deprecate `addresses` and `reqSigs` from rpc outputs

1) add a new sane "address" field (for outputs that have an
   identifiable address, which doesn't include bare multisig)
2) with -deprecatedrpc: leave "reqSigs" and "addresses" intact
   (with all weird/wrong behavior they have now)
3) without -deprecatedrpc: drop "reqSigs" and "addresses" entirely,
   always.

3 files changed, 32 insertions, 13 deletions

diff --git a/src/rpc/blockchain.cpp b/src/rpc/blockchain.cpp
index b90dc9bf42..2618776b02 100644
--- a/src/rpc/blockchain.cpp
+++ b/src/rpc/blockchain.cpp
@@ -1113,11 +1113,13 @@ static RPCHelpMan gettxout()
                 {RPCResult::Type::NUM, "confirmations", "The number of confirmations"},
                 {RPCResult::Type::STR_AMOUNT, "value", "The transaction value in " + CURRENCY_UNIT},
                 {RPCResult::Type::OBJ, "scriptPubKey", "", {
-                    {RPCResult::Type::STR_HEX, "asm", ""},
+                    {RPCResult::Type::STR, "asm", ""},
                     {RPCResult::Type::STR_HEX, "hex", ""},
-                    {RPCResult::Type::NUM, "reqSigs", "Number of required signatures"},
-                    {RPCResult::Type::STR_HEX, "type", "The type, eg pubkeyhash"},
-                    {RPCResult::Type::ARR, "addresses", "array of bitcoin addresses", {{RPCResult::Type::STR, "address", "bitcoin address"}}},
+                    {RPCResult::Type::NUM, "reqSigs", /* optional */ true, "(DEPRECATED, returned only if config option -deprecatedrpc=addresses is passed) Number of required signatures"},
+                    {RPCResult::Type::STR, "type", "The type, eg pubkeyhash"},
+                    {RPCResult::Type::STR, "address", /* optional */ true, "bitcoin address (only if a well-defined address exists)"},
+                    {RPCResult::Type::ARR, "addresses", /* optional */ true, "(DEPRECATED, returned only if config option -deprecatedrpc=addresses is passed) Array of bitcoin addresses",
+                        {{RPCResult::Type::STR, "address", "bitcoin address"}}},
                 }},
                 {RPCResult::Type::BOOL, "coinbase", "Coinbase or not"},
             }},
@@ -1775,6 +1777,16 @@ void CalculatePercentilesByWeight(CAmount result[NUM_GETBLOCKSTATS_PERCENTILES],
     }
 }
 
+void ScriptPubKeyToUniv(const CScript& scriptPubKey, UniValue& out, bool fIncludeHex)
+{
+    ScriptPubKeyToUniv(scriptPubKey, out, fIncludeHex, IsDeprecatedRPCEnabled("addresses"));
+}
+
+void TxToUniv(const CTransaction& tx, const uint256& hashBlock, UniValue& entry, bool include_hex, int serialize_flags, const CTxUndo* txundo)
+{
+    TxToUniv(tx, hashBlock, IsDeprecatedRPCEnabled("addresses"), entry, include_hex, serialize_flags, txundo);
+}
+
 template<typename T>
 static inline bool SetHasKeys(const std::set<T>& set) {return false;}
 template<typename T, typename Tk, typename... Args>
diff --git a/src/rpc/blockchain.h b/src/rpc/blockchain.h
index d8cae4dd24..e719dfc702 100644
--- a/src/rpc/blockchain.h
+++ b/src/rpc/blockchain.h
@@ -6,6 +6,7 @@
 #define BITCOIN_RPC_BLOCKCHAIN_H
 
 #include <amount.h>
+#include <core_io.h>
 #include <streams.h>
 #include <sync.h>
 
@@ -54,6 +55,9 @@ 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);
 
+void ScriptPubKeyToUniv(const CScript& scriptPubKey, UniValue& out, bool fIncludeHex);
+void TxToUniv(const CTransaction& tx, const uint256& hashBlock, UniValue& entry, bool include_hex = true, int serialize_flags = 0, const CTxUndo* txundo = nullptr);
+
 NodeContext& EnsureNodeContext(const util::Ref& context);
 CTxMemPool& EnsureMemPool(const util::Ref& context);
 ChainstateManager& EnsureChainman(const util::Ref& context);
diff --git a/src/rpc/rawtransaction.cpp b/src/rpc/rawtransaction.cpp
index 2f92a321f8..7932bd2915 100644
--- a/src/rpc/rawtransaction.cpp
+++ b/src/rpc/rawtransaction.cpp
@@ -35,7 +35,6 @@
 #include <validation.h>
 #include <validationinterface.h>
 
-
 #include <numeric>
 #include <stdint.h>
 
@@ -132,9 +131,10 @@ static RPCHelpMan getrawtransaction()
                                      {
                                          {RPCResult::Type::STR, "asm", "the asm"},
                                          {RPCResult::Type::STR, "hex", "the hex"},
-                                         {RPCResult::Type::NUM, "reqSigs", "The required sigs"},
+                                         {RPCResult::Type::NUM, "reqSigs", /* optional */ true, "(DEPRECATED, returned only if config option -deprecatedrpc=addresses is passed) Number of required signatures"},
                                          {RPCResult::Type::STR, "type", "The type, eg 'pubkeyhash'"},
-                                         {RPCResult::Type::ARR, "addresses", "",
+                                         {RPCResult::Type::STR, "address", /* optional */ true, "bitcoin address (only if a well-defined address exists)"},
+                                         {RPCResult::Type::ARR, "addresses", /* optional */ true, "(DEPRECATED, returned only if config option -deprecatedrpc=addresses is passed) Array of bitcoin addresses",
                                          {
                                              {RPCResult::Type::STR, "address", "bitcoin address"},
                                          }},
@@ -490,9 +490,10 @@ static RPCHelpMan decoderawtransaction()
                                 {
                                     {RPCResult::Type::STR, "asm", "the asm"},
                                     {RPCResult::Type::STR_HEX, "hex", "the hex"},
-                                    {RPCResult::Type::NUM, "reqSigs", "The required sigs"},
+                                    {RPCResult::Type::NUM, "reqSigs", /* optional */ true, "(DEPRECATED, returned only if config option -deprecatedrpc=addresses is passed) Number of required signatures"},
                                     {RPCResult::Type::STR, "type", "The type, eg 'pubkeyhash'"},
-                                    {RPCResult::Type::ARR, "addresses", "",
+                                    {RPCResult::Type::STR, "address", /* optional */ true, "bitcoin address (only if a well-defined address exists)"},
+                                    {RPCResult::Type::ARR, "addresses", /* optional */ true, "(DEPRECATED, returned only if config option -deprecatedrpc=addresses is passed) Array of bitcoin addresses",
                                     {
                                         {RPCResult::Type::STR, "address", "bitcoin address"},
                                     }},
@@ -548,8 +549,9 @@ static RPCHelpMan decodescript()
                     {
                         {RPCResult::Type::STR, "asm", "Script public key"},
                         {RPCResult::Type::STR, "type", "The output type (e.g. "+GetAllOutputTypes()+")"},
-                        {RPCResult::Type::NUM, "reqSigs", "The required signatures"},
-                        {RPCResult::Type::ARR, "addresses", "",
+                        {RPCResult::Type::STR, "address", /* optional */ true, "bitcoin address (only if a well-defined address exists)"},
+                        {RPCResult::Type::NUM, "reqSigs", /* optional */ true, "(DEPRECATED, returned only if config option -deprecatedrpc=addresses is passed) Number of required signatures"},
+                        {RPCResult::Type::ARR, "addresses", /* optional */ true, "(DEPRECATED, returned only if config option -deprecatedrpc=addresses is passed) Array of bitcoin addresses",
                         {
                             {RPCResult::Type::STR, "address", "bitcoin address"},
                         }},
@@ -559,8 +561,9 @@ static RPCHelpMan decodescript()
                             {RPCResult::Type::STR, "asm", "String representation of the script public key"},
                             {RPCResult::Type::STR_HEX, "hex", "Hex string of the script public key"},
                             {RPCResult::Type::STR, "type", "The type of the script public key (e.g. witness_v0_keyhash or witness_v0_scripthash)"},
-                            {RPCResult::Type::NUM, "reqSigs", "The required signatures (always 1)"},
-                            {RPCResult::Type::ARR, "addresses", "(always length 1)",
+                            {RPCResult::Type::STR, "address", /* optional */ true, "bitcoin address (only if a well-defined address exists)"},
+                            {RPCResult::Type::NUM, "reqSigs", /* optional */ true, "(DEPRECATED, returned only if config option -deprecatedrpc=addresses is passed) Number of required signatures"},
+                            {RPCResult::Type::ARR, "addresses", /* optional */ true, "(DEPRECATED, returned only if config option -deprecatedrpc=addresses is passed) Array of bitcoin addresses",
                             {
                                 {RPCResult::Type::STR, "address", "segwit address"},
                             }},