[build] Move rpc utility methods to rpc/util

Moves the following utility methods to rpc/util and moves that unit to
libbitcoin_common so they can be accessed by all libraries.

- `RPCTypeCheck`
- `RPCTypeCheckArgument`
- `RPCTypeCheckObj`
- `AmountFromValue`
- `ParseHashV``ParseHashO`
- `ParseHexV`
- `ParseHexO`
- `HelpExampleCli`
- `HelpExampleRpc`

1 files changed, 104 insertions, 0 deletions

diff --git a/src/rpc/util.cpp b/src/rpc/util.cpp
index 10979b43b0..78e9191409 100644
--- a/src/rpc/util.cpp
+++ b/src/rpc/util.cpp
@@ -10,6 +10,110 @@
 
 InitInterfaces* g_rpc_interfaces = nullptr;
 
+void RPCTypeCheck(const UniValue& params,
+                  const std::list<UniValueType>& typesExpected,
+                  bool fAllowNull)
+{
+    unsigned int i = 0;
+    for (const UniValueType& t : typesExpected) {
+        if (params.size() <= i)
+            break;
+
+        const UniValue& v = params[i];
+        if (!(fAllowNull && v.isNull())) {
+            RPCTypeCheckArgument(v, t);
+        }
+        i++;
+    }
+}
+
+void RPCTypeCheckArgument(const UniValue& value, const UniValueType& typeExpected)
+{
+    if (!typeExpected.typeAny && value.type() != typeExpected.type) {
+        throw JSONRPCError(RPC_TYPE_ERROR, strprintf("Expected type %s, got %s", uvTypeName(typeExpected.type), uvTypeName(value.type())));
+    }
+}
+
+void RPCTypeCheckObj(const UniValue& o,
+    const std::map<std::string, UniValueType>& typesExpected,
+    bool fAllowNull,
+    bool fStrict)
+{
+    for (const auto& t : typesExpected) {
+        const UniValue& v = find_value(o, t.first);
+        if (!fAllowNull && v.isNull())
+            throw JSONRPCError(RPC_TYPE_ERROR, strprintf("Missing %s", t.first));
+
+        if (!(t.second.typeAny || v.type() == t.second.type || (fAllowNull && v.isNull()))) {
+            std::string err = strprintf("Expected type %s for %s, got %s",
+                uvTypeName(t.second.type), t.first, uvTypeName(v.type()));
+            throw JSONRPCError(RPC_TYPE_ERROR, err);
+        }
+    }
+
+    if (fStrict)
+    {
+        for (const std::string& k : o.getKeys())
+        {
+            if (typesExpected.count(k) == 0)
+            {
+                std::string err = strprintf("Unexpected key %s", k);
+                throw JSONRPCError(RPC_TYPE_ERROR, err);
+            }
+        }
+    }
+}
+
+CAmount AmountFromValue(const UniValue& value)
+{
+    if (!value.isNum() && !value.isStr())
+        throw JSONRPCError(RPC_TYPE_ERROR, "Amount is not a number or string");
+    CAmount amount;
+    if (!ParseFixedPoint(value.getValStr(), 8, &amount))
+        throw JSONRPCError(RPC_TYPE_ERROR, "Invalid amount");
+    if (!MoneyRange(amount))
+        throw JSONRPCError(RPC_TYPE_ERROR, "Amount out of range");
+    return amount;
+}
+
+uint256 ParseHashV(const UniValue& v, std::string strName)
+{
+    std::string strHex(v.get_str());
+    if (64 != strHex.length())
+        throw JSONRPCError(RPC_INVALID_PARAMETER, strprintf("%s must be of length %d (not %d, for '%s')", strName, 64, strHex.length(), strHex));
+    if (!IsHex(strHex)) // Note: IsHex("") is false
+        throw JSONRPCError(RPC_INVALID_PARAMETER, strName+" must be hexadecimal string (not '"+strHex+"')");
+    return uint256S(strHex);
+}
+uint256 ParseHashO(const UniValue& o, std::string strKey)
+{
+    return ParseHashV(find_value(o, strKey), strKey);
+}
+std::vector<unsigned char> ParseHexV(const UniValue& v, std::string strName)
+{
+    std::string strHex;
+    if (v.isStr())
+        strHex = v.get_str();
+    if (!IsHex(strHex))
+        throw JSONRPCError(RPC_INVALID_PARAMETER, strName+" must be hexadecimal string (not '"+strHex+"')");
+    return ParseHex(strHex);
+}
+std::vector<unsigned char> ParseHexO(const UniValue& o, std::string strKey)
+{
+    return ParseHexV(find_value(o, strKey), strKey);
+}
+
+std::string HelpExampleCli(const std::string& methodname, const std::string& args)
+{
+    return "> bitcoin-cli " + methodname + " " + args + "\n";
+}
+
+std::string HelpExampleRpc(const std::string& methodname, const std::string& args)
+{
+    return "> curl --user myusername --data-binary '{\"jsonrpc\": \"1.0\", \"id\":\"curltest\", "
+        "\"method\": \"" + methodname + "\", \"params\": [" + args + "] }' -H 'content-type: text/plain;' http://127.0.0.1:8332/\n";
+}
+
 // Converts a hex string to a public key if possible
 CPubKey HexToPubKey(const std::string& hex_in)
 {