// Copyright (c) 2013 Conformal Systems LLC.
// Use of this source code is governed by an ISC
// license that can be found in the LICENSE file.
package btcjson
import (
"encoding/json"
"fmt"
)
// Message contains a message to be sent to the bitcoin client.
type Message struct {
Jsonrpc string `json:"jsonrpc"`
Id interface{} `json:"id"`
Method string `json:"method"`
Params interface{} `json:"params"`
}
// Reply is the general form of the reply from the bitcoin client.
// The form of the Result part varies from one command to the next so it
// is currently implemented as an interface.
type Reply struct {
Result interface{} `json:"result"`
Error *Error `json:"error"`
// This has to be a pointer for go to put a null in it when empty.
Id *interface{} `json:"id"`
}
// InfoResult contains the data returned by the getinfo command.
type InfoResult struct {
Version int `json:"version,omitempty"`
ProtocolVersion int `json:"protocolversion,omitempty"`
WalletVersion int `json:"walletversion,omitempty"`
Balance float64 `json:"balance,omitempty"`
Blocks int `json:"blocks,omitempty"`
Connections int `json:"connections,omitempty"`
Proxy string `json:"proxy,omitempty"`
Difficulty float64 `json:"difficulty,omitempty"`
TestNet bool `json:"testnet,omitempty"`
KeypoolOldest int64 `json:"keypoololdest,omitempty"`
KeypoolSize int `json:"keypoolsize,omitempty"`
PaytxFee float64 `json:"paytxfee,omitempty"`
Errors string `json:"errors,omitempty"`
}
// BlockResult models the data from the getblock command.
type BlockResult struct {
Hash string `json:"hash"`
Confirmations uint64 `json:"confirmations"`
Size int `json:"size"`
Height int64 `json:"height"`
Version uint32 `json:"version"`
MerkleRoot string `json:"merkleroot"`
Tx []string `json:"tx"`
Time int64 `json:"time"`
Nonce uint32 `json:"nonce"`
Bits string `json:"bits"`
Difficulty float64 `json:"difficulty"`
PreviousHash string `json:"previousblockhash"`
NextHash string `json:"nextblockhash"`
}
// TxRawResult models the data from the getrawtransaction command.
type TxRawResult struct {
Hex string `json:"hex"`
Txid string `json:"txid"`
Version uint32 `json:"version"`
LockTime uint32 `json:"locktime"`
Vin []Vin `json:"vin"`
Vout []Vout `json:"vout"`
BlockHash string `json:"blockhash"`
Confirmations uint64 `json:"confirmations"`
Time int64 `json:"time"`
Blocktime int64 `json:"blocktime"`
}
// TxRawDecodeResult models the data from the decoderawtransaction command.
type TxRawDecodeResult struct {
Txid string `json:"txid"`
Version uint32 `json:"version"`
Locktime int `json:"locktime"`
Vin []Vin `json:"vin"`
Vout []Vout `json:"vout"`
}
// Vin models parts of the tx data. It is defined seperately since both
// getrawtransaction and decoderawtransaction use the same structure.
type Vin struct {
Coinbase string `json:"coinbase,omitempty"`
Vout int `json:"vout,omitempty"`
ScriptSig struct {
Txid string `json:"txid"`
Asm string `json:"asm"`
Hex string `json:"hex"`
} `json:"scriptSig,omitempty"`
Sequence float64 `json:"sequence"`
}
// Vout models parts of the tx data. It is defined seperately since both
// getrawtransaction and decoderawtransaction use the same structure.
type Vout struct {
Value float64 `json:"value"`
N int `json:"n"`
ScriptPubKey struct {
Asm string `json:"asm"`
Hex string `json:"hex"`
ReqSig int `json:"reqSig"`
Type string `json:"type"`
Addresses []string `json:"addresses"`
} `json:"scriptPubKey"`
}
// Error models the error field of the json returned by a bitcoin client. When
// there is no error, this should be a nil pointer to produce the null in the
// json that bitcoind produces.
type Error struct {
Code int `json:"code,omitempty"`
Message string `json:"message,omitempty"`
}
// jsonWithArgs takes a command and an interface which contains an array
// of the arguments for that command. It knows NOTHING about the commands so
// all error checking of the arguments must happen before it is called.
func jsonWithArgs(command string, args interface{}) ([]byte, error) {
rawMessage := Message{"1.0", "btcd", command, args}
finalMessage, err := json.Marshal(rawMessage)
if err != nil {
return nil, err
}
return finalMessage, nil
}
// CreateMessage takes a string and the optional arguments for it. Then,
// if it is a recognized bitcoin json message, generates the json message ready
// to send off to the daemon or server.
// It is capable of handeling all of the commands from the standard client,
// described at:
// https://en.bitcoin.it/wiki/Original_Bitcoin_client/API_Calls_list
func CreateMessage(message string, args ...interface{}) ([]byte, error) {
var finalMessage []byte
var err error
// Different commands have different required and optional arguments.
// Need to handle them based on that.
switch message {
// No args
case "getblockcount", "getblocknumber", "getconnectioncount",
"getdifficulty", "getgenerate", "gethashespersec", "getinfo",
"getmininginfo", "getpeerinfo", "getrawmempool",
"keypoolrefill", "listaddressgroupings", "listlockunspent",
"stop", "walletlock":
if len(args) > 0 {
err = fmt.Errorf("Too many arguments for %s", message)
return finalMessage, err
}
finalMessage, err = jsonWithArgs(message, args)
// One optional int
case "listaccounts":
if len(args) > 1 {
err = fmt.Errorf("Too many arguments for %s", message)
return finalMessage, err
}
if len(args) == 1 {
_, ok := args[0].(int)
if !ok {
err = fmt.Errorf("Argument must be int for %s", message)
return finalMessage, err
}
}
finalMessage, err = jsonWithArgs(message, args)
// One required int
case "getblockhash":
if len(args) != 1 {
err = fmt.Errorf("Missing argument for %s", message)
return finalMessage, err
}
_, ok := args[0].(int)
if !ok {
err = fmt.Errorf("Argument must be int for %s", message)
return finalMessage, err
}
finalMessage, err = jsonWithArgs(message, args)
// One required float
case "settxfee":
if len(args) != 1 {
err = fmt.Errorf("Missing argument for %s", message)
return finalMessage, err
}
_, ok := args[0].(float64)
if !ok {
err = fmt.Errorf("Argument must be float64 for %s", message)
return finalMessage, err
}
finalMessage, err = jsonWithArgs(message, args)
// One optional string
case "getmemorypool", "getnewaddress", "getwork", "help":
if len(args) > 1 {
err = fmt.Errorf("Too many arguments for %s", message)
return finalMessage, err
}
if len(args) == 1 {
_, ok := args[0].(string)
if !ok {
err = fmt.Errorf("Optional argument must be string for %s", message)
return finalMessage, err
}
}
finalMessage, err = jsonWithArgs(message, args)
// One required string
case "backupwallet", "decoderawtransaction", "dumpprivkey",
"encryptwallet", "getaccount", "getaccountaddress",
"getaddressbyaccount", "getblock",
"gettransaction", "sendrawtransaction", "validateaddress":
if len(args) != 1 {
err = fmt.Errorf("%s requires one argument", message)
return finalMessage, err
}
_, ok := args[0].(string)
if !ok {
err = fmt.Errorf("Argument must be string for %s", message)
return finalMessage, err
}
finalMessage, err = jsonWithArgs(message, args)
// Two required strings
case "listsinceblock", "setaccount", "signmessage", "walletpassphrase",
"walletpassphrasechange":
if len(args) != 2 {
err = fmt.Errorf("Missing arguments for %s", message)
return finalMessage, err
}
_, ok1 := args[0].(string)
_, ok2 := args[1].(string)
if !ok1 || !ok2 {
err = fmt.Errorf("Arguments must be string for %s", message)
return finalMessage, err
}
finalMessage, err = jsonWithArgs(message, args)
// Three required strings
case "verifymessage":
if len(args) != 3 {
err = fmt.Errorf("Three arguments required for %s", message)
return finalMessage, err
}
_, ok1 := args[0].(string)
_, ok2 := args[1].(string)
_, ok3 := args[2].(string)
if !ok1 || !ok2 || !ok3 {
err = fmt.Errorf("Arguments must be string for %s", message)
return finalMessage, err
}
finalMessage, err = jsonWithArgs(message, args)
// One required bool, one optional string
case "getaddednodeinfo":
if len(args) > 2 || len(args) == 0 {
err = fmt.Errorf("Wrong number of arguments for %s", message)
return finalMessage, err
}
_, ok1 := args[0].(bool)
ok2 := true
if len(args) == 2 {
_, ok2 = args[1].(string)
}
if !ok1 || !ok2 {
err = fmt.Errorf("Arguments must be bool and optionally string for %s", message)
return finalMessage, err
}
finalMessage, err = jsonWithArgs(message, args)
// One required bool, one optional int
case "setgenerate":
if len(args) > 2 || len(args) == 0 {
err = fmt.Errorf("Wrong number of argument for %s", message)
return finalMessage, err
}
_, ok1 := args[0].(bool)
ok2 := true
if len(args) == 2 {
_, ok2 = args[1].(int)
}
if !ok1 || !ok2 {
err = fmt.Errorf("Arguments must be bool and optionally int for %s", message)
return finalMessage, err
}
finalMessage, err = jsonWithArgs(message, args)
// One optional string, one optional int
case "getbalance", "getreceivedbyaccount":
if len(args) > 2 {
err = fmt.Errorf("Wrong number of arguments for %s", message)
return finalMessage, err
}
ok1 := true
ok2 := true
if len(args) >= 1 {
_, ok1 = args[0].(string)
}
if len(args) == 2 {
_, ok2 = args[1].(int)
}
if !ok1 || !ok2 {
err = fmt.Errorf("Optional arguments must be string and int for %s", message)
return finalMessage, err
}
finalMessage, err = jsonWithArgs(message, args)
// One required string, one optional int
case "addnode", "getrawtransaction", "getreceivedbyaddress":
if len(args) > 2 || len(args) == 0 {
err = fmt.Errorf("Wrong number of argument for %s", message)
return finalMessage, err
}
_, ok1 := args[0].(string)
ok2 := true
if len(args) == 2 {
_, ok2 = args[1].(int)
}
if !ok1 || !ok2 {
err = fmt.Errorf("Arguments must be string and optionally int for %s", message)
return finalMessage, err
}
finalMessage, err = jsonWithArgs(message, args)
// One optional int, one optional bool
case "listreceivedbyaccount", "listreceivedbyaddress":
if len(args) > 2 {
err = fmt.Errorf("Wrong number of argument for %s", message)
return finalMessage, err
}
ok1 := true
ok2 := true
if len(args) >= 1 {
_, ok1 = args[0].(int)
}
if len(args) == 2 {
_, ok2 = args[1].(bool)
}
if !ok1 || !ok2 {
err = fmt.Errorf("Optional arguments must be int and bool for %s", message)
return finalMessage, err
}
finalMessage, err = jsonWithArgs(message, args)
// One optional string, two optional ints
case "listtransactions":
if len(args) > 3 {
err = fmt.Errorf("Wrong number of arguments for %s", message)
return finalMessage, err
}
ok1 := true
ok2 := true
ok3 := true
if len(args) >= 1 {
_, ok1 = args[0].(string)
}
if len(args) > 1 {
_, ok2 = args[1].(int)
}
if len(args) == 3 {
_, ok3 = args[2].(int)
}
if !ok1 || !ok2 || !ok3 {
err = fmt.Errorf("Optional arguments must be string and up to two ints for %s", message)
return finalMessage, err
}
finalMessage, err = jsonWithArgs(message, args)
// One required string, one optional string, one optional bool
case "importprivkey":
if len(args) > 3 || len(args) == 0 {
err = fmt.Errorf("Wrong number of arguments for %s", message)
return finalMessage, err
}
_, ok1 := args[0].(string)
ok2 := true
ok3 := true
if len(args) > 1 {
_, ok2 = args[1].(string)
}
if len(args) == 3 {
_, ok3 = args[2].(bool)
}
if !ok1 || !ok2 || !ok3 {
err = fmt.Errorf("Arguments must be string and optionally string and bool for %s", message)
return finalMessage, err
}
finalMessage, err = jsonWithArgs(message, args)
// Two optional ints
case "listunspent":
if len(args) > 2 {
err = fmt.Errorf("Wrong number of arguments for %s", message)
return finalMessage, err
}
ok1 := true
ok2 := true
if len(args) >= 1 {
_, ok1 = args[0].(int)
}
if len(args) == 2 {
_, ok2 = args[1].(int)
}
if !ok1 || !ok2 {
err = fmt.Errorf("Optional arguments must be ints for %s", message)
return finalMessage, err
}
finalMessage, err = jsonWithArgs(message, args)
// Two required strings, one required float, one optional int,
// two optional strings.
case "sendfrom":
if len(args) > 6 || len(args) < 3 {
err = fmt.Errorf("Wrong number of arguments for %s", message)
return finalMessage, err
}
_, ok1 := args[0].(string)
_, ok2 := args[1].(string)
_, ok3 := args[2].(float64)
ok4 := true
ok5 := true
ok6 := true
if len(args) >= 4 {
_, ok4 = args[3].(int)
}
if len(args) >= 5 {
_, ok5 = args[4].(string)
}
if len(args) == 6 {
_, ok6 = args[5].(string)
}
if !ok1 || !ok2 || !ok3 || !ok4 || !ok5 || !ok6 {
err = fmt.Errorf("Arguments must be string, string, float64 and optionally int and two strings for %s", message)
return finalMessage, err
}
finalMessage, err = jsonWithArgs(message, args)
// Two required strings, one required float, one optional int,
// one optional string.
case "move":
if len(args) > 5 || len(args) < 3 {
err = fmt.Errorf("Wrong number of arguments for %s", message)
return finalMessage, err
}
_, ok1 := args[0].(string)
_, ok2 := args[1].(string)
_, ok3 := args[2].(float64)
ok4 := true
ok5 := true
if len(args) >= 4 {
_, ok4 = args[3].(int)
}
if len(args) == 5 {
_, ok5 = args[4].(string)
}
if !ok1 || !ok2 || !ok3 || !ok4 || !ok5 {
err = fmt.Errorf("Arguments must be string, string, float64 and optionally int and string for %s", message)
return finalMessage, err
}
finalMessage, err = jsonWithArgs(message, args)
// One required strings, one required float, two optional strings
case "sendtoaddress":
if len(args) > 4 || len(args) < 2 {
err = fmt.Errorf("Wrong number of arguments for %s", message)
return finalMessage, err
}
_, ok1 := args[0].(string)
_, ok2 := args[1].(float64)
ok3 := true
ok4 := true
if len(args) >= 3 {
_, ok3 = args[2].(string)
}
if len(args) == 4 {
_, ok4 = args[3].(string)
}
if !ok1 || !ok2 || !ok3 || !ok4 {
err = fmt.Errorf("Arguments must be string, float64 and optionally two strings for %s", message)
return finalMessage, err
}
finalMessage, err = jsonWithArgs(message, args)
// required int, required pair of keys (string), optional string
case "addmultisignaddress":
if len(args) > 4 || len(args) < 3 {
err = fmt.Errorf("Wrong number of arguments for %s", message)
return finalMessage, err
}
_, ok1 := args[0].(int)
_, ok2 := args[1].(string)
_, ok3 := args[2].(string)
ok4 := true
if len(args) == 4 {
_, ok4 = args[2].(string)
}
if !ok1 || !ok2 || !ok3 || !ok4 {
err = fmt.Errorf("Arguments must be int, two string and optionally one for %s", message)
return finalMessage, err
}
finalMessage, err = jsonWithArgs(message, args)
// Must be a set of 3 strings and a float (any number of those)
case "createrawtransaction":
if len(args)%4 != 0 || len(args) == 0 {
err = fmt.Errorf("Wrong number of arguments for %s", message)
return finalMessage, err
}
type vlist struct {
Vin string `json:"vin"`
Vout string `json:"vout"`
}
vList := make([]vlist, len(args)/4)
addresses := make(map[string]float64)
for i := 0; i < len(args)/4; i += 1 {
vin, ok1 := args[(i*4)+0].(string)
vout, ok2 := args[(i*4)+1].(string)
add, ok3 := args[(i*4)+2].(string)
amt, ok4 := args[(i*4)+3].(float64)
if !ok1 || !ok2 || !ok3 || !ok4 {
err = fmt.Errorf("Incorrect arguement types.")
return finalMessage, err
}
vList[i].Vin = vin
vList[i].Vout = vout
addresses[add] = amt
}
finalMessage, err = jsonWithArgs(message, []interface{}{vList, addresses})
// string, string/float pairs, optional int, and string
case "sendmany":
if len(args) < 3 {
err = fmt.Errorf("Wrong number of arguments for %s", message)
return finalMessage, err
}
var minconf int
var comment string
_, ok1 := args[0].(string)
if !ok1 {
err = fmt.Errorf("Incorrect arguement types.")
return finalMessage, err
}
addresses := make(map[string]float64)
for i := 1; i < len(args); i += 2 {
add, ok1 := args[i].(string)
if ok1 {
if len(args) > i+1 {
amt, ok2 := args[i+1].(float64)
if !ok2 {
err = fmt.Errorf("Incorrect arguement types.")
return finalMessage, err
}
// Put a single pair into addresses
addresses[add] = amt
} else {
comment = add
}
} else {
if _, ok := args[i].(int); ok {
minconf = args[i].(int)
}
if len(args)-1 > i {
if _, ok := args[i+1].(string); ok {
comment = args[i+1].(string)
}
}
}
}
finalMessage, err = jsonWithArgs(message, []interface{}{args[0].(string), addresses, minconf, comment})
// bool and an array of stuff
case "lockunspent":
if len(args) < 2 {
err = fmt.Errorf("Wrong number of arguments for %s", message)
return finalMessage, err
}
_, ok1 := args[0].(bool)
if !ok1 {
err = fmt.Errorf("Incorrect arguement types.")
return finalMessage, err
}
finalMessage, err = jsonWithArgs(message, args)
// one required string (hex) and at least one set of 4 other strings.
case "signrawtransaction":
if (len(args)-1)%4 != 0 || len(args) < 5 {
err = fmt.Errorf("Wrong number of arguments for %s", message)
return finalMessage, err
}
_, ok1 := args[0].(string)
if !ok1 {
err = fmt.Errorf("Incorrect arguement types.")
return finalMessage, err
}
type txlist struct {
Txid string `json:"txid"`
Vout string `json:"vout"`
ScriptPubKey string `json:"scriptPubKey"`
}
txList := make([]txlist, (len(args)-1)/4)
pkeyList := make([]string, (len(args)-1)/4)
for i := 0; i < len(args)/4; i += 1 {
txid, ok1 := args[(i*4)+0].(string)
vout, ok2 := args[(i*4)+1].(string)
spkey, ok3 := args[(i*4)+2].(string)
pkey, ok4 := args[(i*4)+3].(string)
if !ok1 || !ok2 || !ok3 || !ok4 {
err = fmt.Errorf("Incorrect arguement types.")
return finalMessage, err
}
txList[i].Txid = txid
txList[i].Vout = vout
txList[i].ScriptPubKey = spkey
pkeyList[i] = pkey
}
finalMessage, err = jsonWithArgs(message, []interface{}{args[0].(string), txList, pkeyList})
// Any other message
default:
err = fmt.Errorf("Not a valid command: %s", message)
}
return finalMessage, err
}
// readResultCmd unmarshalls the json reply with data struct for specific
// commands or an interface if it is not a command where we already have a
// struct ready.
func readResultCmd(cmd string, message []byte) (Reply, error) {
var result Reply
var err error
var objmap map[string]json.RawMessage
err = json.Unmarshal(message, &objmap)
if err != nil {
err = fmt.Errorf("Error unmarshalling json reply: %v", err)
return result, err
}
// Take care of the parts that are the same for all replies.
var jsonErr Error
var id interface{}
err = json.Unmarshal(objmap["error"], &jsonErr)
if err != nil {
err = fmt.Errorf("Error unmarshalling json reply: %v", err)
return result, err
}
err = json.Unmarshal(objmap["id"], &id)
if err != nil {
err = fmt.Errorf("Error unmarshalling json reply: %v", err)
return result, err
}
// If it is a command where we have already worked out the reply,
// generate put the results in the proper structure.
switch cmd {
case "getinfo":
var res InfoResult
err = json.Unmarshal(objmap["result"], &res)
if err != nil {
err = fmt.Errorf("Error unmarshalling json reply: %v", err)
return result, err
}
result.Result = res
case "getblock":
var res BlockResult
err = json.Unmarshal(objmap["result"], &res)
if err != nil {
err = fmt.Errorf("Error unmarshalling json reply: %v", err)
return result, err
}
result.Result = res
case "getrawtransaction":
var res TxRawResult
err = json.Unmarshal(objmap["result"], &res)
if err != nil {
err = fmt.Errorf("Error unmarshalling json reply: %v", err)
return result, err
}
result.Result = res
case "decoderawtransaction":
var res TxRawDecodeResult
err = json.Unmarshal(objmap["result"], &res)
if err != nil {
err = fmt.Errorf("Error unmarshalling json reply: %v", err)
return result, err
}
result.Result = res
// For anything else put it in an interface. All the data is still
// there, just a little less convenient to deal with.
default:
err = json.Unmarshal(message, &result)
if err != nil {
err = fmt.Errorf("Error unmarshalling json reply: %v", err)
return result, err
}
}
// Only want the error field when there is an actual error to report.
if jsonErr.Code != 0 {
result.Error = &jsonErr
}
result.Id = &id
return result, err
}
// RpcCommand takes a message generated from one of the routines above
// along with the login/server info, sends it, and gets a reply, returning
// a go struct with the result.
func RpcCommand(user string, password string, server string, message []byte) (Reply, error) {
var result Reply
// Need this so we can tell what kind of message we are sending
// so we can unmarshal it properly.
var method string
var msg interface{}
err := json.Unmarshal(message, &msg)
if err != nil {
err := fmt.Errorf("Error, message does not appear to be valid json: %v", err)
return result, err
}
m := msg.(map[string]interface{})
for k, v := range m {
if k == "method" {
method = v.(string)
}
}
if method == "" {
err := fmt.Errorf("Error, no method specified.")
return result, err
}
resp, err := jsonRpcSend(user, password, server, message)
if err != nil {
err := fmt.Errorf("Error sending json message: "+err.Error())
return result, err
}
body, err := GetRaw(resp.Body)
if err != nil {
err := fmt.Errorf("Error getting json reply: %v", err)
return result, err
}
result, err = readResultCmd(method, body)
if err != nil {
err := fmt.Errorf("Error reading json message: %v", err)
return result, err
}
return result, err
}
// IsValidIdType checks that the Id field (which can go in any of the json
// messages is valid. json rpc 1.0 allows any (json) type, but we still need
// to prevent values that cannot be marshalled from going in. json rpc 2.0
// (which bitcoind follows for some parts) only allows string, number, or null,
// so we restrict to that list. Ths is only necessary if you manually marshal
// a message. The normal btcjson functions only use string ids.
func IsValidIdType(id interface{}) bool {
switch id.(type) {
case int, int8, int16, int32, int64,
uint, uint8, uint16, uint32, uint64,
float32, float64,
string,
nil:
return true
default:
return false
}
}