refactor: move verbosity parsing to rpc/util

Provides a common way for rpcs to obtain
verbosity from an rpc parameter

Author: tdb3

src/rpc/blockchain.cpp

@@ -766,14 +766,7 @@ static RPCHelpMan getblock()
 {
     uint256 hash(ParseHashV(request.params[0], "blockhash"));
 
-    int verbosity = 1;
-    if (!request.params[1].isNull()) {
-        if (request.params[1].isBool()) {
-            verbosity = request.params[1].get_bool() ? 1 : 0;
-        } else {
-            verbosity = request.params[1].getInt<int>();
-        }
-    }
+    int verbosity{ParseVerbosity(request.params[1], /*default_verbosity=*/1)};
 
     const CBlockIndex* pblockindex;
     const CBlockIndex* tip;

src/rpc/rawtransaction.cpp

@@ -338,15 +338,7 @@ static RPCHelpMan getrawtransaction()
         throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "The genesis block coinbase is not considered an ordinary transaction and cannot be retrieved");
     }
 
-    // Accept either a bool (true) or a num (>=0) to indicate verbosity.
-    int verbosity{0};
-    if (!request.params[1].isNull()) {
-        if (request.params[1].isBool()) {
-            verbosity = request.params[1].get_bool();
-        } else {
-            verbosity = request.params[1].getInt<int>();
-        }
-    }
+    int verbosity{ParseVerbosity(request.params[1], /*default_verbosity=*/0)};
 
     if (!request.params[2].isNull()) {
         LOCK(cs_main);

src/rpc/util.cpp

@@ -81,6 +81,18 @@ void RPCTypeCheckObj(const UniValue& o,
     }
 }
 
+int ParseVerbosity(const UniValue& arg, int default_verbosity)
+{
+    if (!arg.isNull()) {
+        if (arg.isBool()) {
+            return arg.get_bool(); // true = 1
+        } else {
+            return arg.getInt<int>();
+        }
+    }
+    return default_verbosity;
+}
+
 CAmount AmountFromValue(const UniValue& value, int decimals)
 {
     if (!value.isNum() && !value.isStr())

src/rpc/util.h

@@ -100,6 +100,15 @@ uint256 ParseHashO(const UniValue& o, std::string_view strKey);
 std::vector<unsigned char> ParseHexV(const UniValue& v, std::string_view name);
 std::vector<unsigned char> ParseHexO(const UniValue& o, std::string_view strKey);
 
+/**
+ * Parses verbosity from provided UniValue.
+ *
+ * @param[in] arg The verbosity argument as a bool (true) or int (0, 1, 2,...)
+ * @param[in] default_verbosity The value to return if verbosity argument is null
+ * @returns An integer describing the verbosity level (e.g. 0, 1, 2, etc.)
+ */
+int ParseVerbosity(const UniValue& arg, int default_verbosity);
+
 /**
  * Validate and return a CAmount from a UniValue number or string.
  *