neoneo-go/pkg/rpc/client/nep5.go

212 lines
6.6 KiB
Go
Raw Normal View History

2020-03-06 11:56:55 +00:00
package client
import (
"errors"
"fmt"
"github.com/nspcc-dev/neo-go/pkg/core/transaction"
"github.com/nspcc-dev/neo-go/pkg/encoding/address"
"github.com/nspcc-dev/neo-go/pkg/encoding/bigint"
"github.com/nspcc-dev/neo-go/pkg/io"
2020-03-06 11:56:55 +00:00
"github.com/nspcc-dev/neo-go/pkg/smartcontract"
"github.com/nspcc-dev/neo-go/pkg/util"
"github.com/nspcc-dev/neo-go/pkg/vm/emit"
"github.com/nspcc-dev/neo-go/pkg/vm/opcode"
"github.com/nspcc-dev/neo-go/pkg/wallet"
2020-03-06 11:56:55 +00:00
)
var (
// NeoContractHash is a hash of the NEO native contract.
NeoContractHash, _ = util.Uint160DecodeStringLE("9bde8f209c88dd0e7ca3bf0af0f476cdd8207789")
// GasContractHash is a hash of the GAS native contract.
GasContractHash, _ = util.Uint160DecodeStringLE("8c23f196d8a1bfd103a9dcb1f9ccf0c611377d3b")
)
2020-03-06 11:56:55 +00:00
// NEP5Decimals invokes `decimals` NEP5 method on a specified contract.
func (c *Client) NEP5Decimals(tokenHash util.Uint160) (int64, error) {
result, err := c.InvokeFunction(tokenHash, "decimals", []smartcontract.Parameter{}, nil)
2020-03-06 11:56:55 +00:00
if err != nil {
return 0, err
} else if result.State != "HALT" || len(result.Stack) == 0 {
return 0, errors.New("invalid VM state")
}
return topIntFromStack(result.Stack)
}
// NEP5Name invokes `name` NEP5 method on a specified contract.
func (c *Client) NEP5Name(tokenHash util.Uint160) (string, error) {
result, err := c.InvokeFunction(tokenHash, "name", []smartcontract.Parameter{}, nil)
2020-03-06 11:56:55 +00:00
if err != nil {
return "", err
} else if result.State != "HALT" || len(result.Stack) == 0 {
return "", errors.New("invalid VM state")
}
return topStringFromStack(result.Stack)
}
// NEP5Symbol invokes `symbol` NEP5 method on a specified contract.
func (c *Client) NEP5Symbol(tokenHash util.Uint160) (string, error) {
result, err := c.InvokeFunction(tokenHash, "symbol", []smartcontract.Parameter{}, nil)
2020-03-06 11:56:55 +00:00
if err != nil {
return "", err
} else if result.State != "HALT" || len(result.Stack) == 0 {
return "", errors.New("invalid VM state")
}
return topStringFromStack(result.Stack)
}
// NEP5TotalSupply invokes `totalSupply` NEP5 method on a specified contract.
func (c *Client) NEP5TotalSupply(tokenHash util.Uint160) (int64, error) {
result, err := c.InvokeFunction(tokenHash, "totalSupply", []smartcontract.Parameter{}, nil)
2020-03-06 11:56:55 +00:00
if err != nil {
return 0, err
} else if result.State != "HALT" || len(result.Stack) == 0 {
return 0, errors.New("invalid VM state")
}
return topIntFromStack(result.Stack)
}
// NEP5BalanceOf invokes `balanceOf` NEP5 method on a specified contract.
func (c *Client) NEP5BalanceOf(tokenHash util.Uint160) (int64, error) {
result, err := c.InvokeFunction(tokenHash, "balanceOf", []smartcontract.Parameter{}, nil)
2020-03-06 11:56:55 +00:00
if err != nil {
return 0, err
} else if result.State != "HALT" || len(result.Stack) == 0 {
return 0, errors.New("invalid VM state")
}
return topIntFromStack(result.Stack)
}
// NEP5TokenInfo returns full NEP5 token info.
func (c *Client) NEP5TokenInfo(tokenHash util.Uint160) (*wallet.Token, error) {
name, err := c.NEP5Name(tokenHash)
if err != nil {
return nil, err
}
symbol, err := c.NEP5Symbol(tokenHash)
if err != nil {
return nil, err
}
decimals, err := c.NEP5Decimals(tokenHash)
if err != nil {
return nil, err
}
return wallet.NewToken(tokenHash, name, symbol, decimals), nil
}
// CreateNEP5TransferTx creates an invocation transaction for the 'transfer'
// method of a given contract (token) to move specified amount of NEP5 assets
// (in FixedN format using contract's number of decimals) to given account and
// returns it. The returned transaction is not signed.
func (c *Client) CreateNEP5TransferTx(acc *wallet.Account, to util.Uint160, token util.Uint160, amount int64, gas int64) (*transaction.Transaction, error) {
from, err := address.StringToUint160(acc.Address)
if err != nil {
return nil, fmt.Errorf("bad account address: %v", err)
}
// Note: we don't use invoke function here because it requires
// 2 round trips instead of one.
w := io.NewBufBinWriter()
emit.AppCallWithOperationAndArgs(w.BinWriter, token, "transfer", from, to, amount)
emit.Opcode(w.BinWriter, opcode.ASSERT)
script := w.Bytes()
result, err := c.InvokeScript(script, []transaction.Cosigner{
{
Account: from,
Scopes: transaction.CalledByEntry,
},
})
if err != nil {
return nil, fmt.Errorf("can't add system fee to transaction: %v", err)
}
tx := transaction.New(c.opts.Network, script, result.GasConsumed)
tx.Sender = from
tx.Cosigners = []transaction.Cosigner{
{
Account: from,
Scopes: transaction.CalledByEntry,
},
}
tx.ValidUntilBlock, err = c.CalculateValidUntilBlock()
if err != nil {
return nil, fmt.Errorf("can't calculate validUntilBlock: %v", err)
}
err = c.AddNetworkFee(tx, gas, acc)
if err != nil {
return nil, fmt.Errorf("can't add network fee to transaction: %v", err)
}
return tx, nil
}
// TransferNEP5 creates an invocation transaction that invokes 'transfer' method
// on a given token to move specified amount of NEP5 assets (in FixedN format
// using contract's number of decimals) to given account and sends it to the
// network returning just a hash of it.
func (c *Client) TransferNEP5(acc *wallet.Account, to util.Uint160, token util.Uint160, amount int64, gas int64) (util.Uint256, error) {
tx, err := c.CreateNEP5TransferTx(acc, to, token, amount, gas)
if err != nil {
return util.Uint256{}, err
}
if err := acc.SignTx(tx); err != nil {
return util.Uint256{}, fmt.Errorf("can't sign tx: %v", err)
}
if err := c.SendRawTransaction(tx); err != nil {
return util.Uint256{}, err
}
return tx.Hash(), nil
}
2020-03-06 11:56:55 +00:00
func topIntFromStack(st []smartcontract.Parameter) (int64, error) {
index := len(st) - 1 // top stack element is last in the array
var decimals int64
switch typ := st[index].Type; typ {
case smartcontract.IntegerType:
var ok bool
decimals, ok = st[index].Value.(int64)
if !ok {
return 0, errors.New("invalid Integer item")
}
case smartcontract.ByteArrayType:
data, ok := st[index].Value.([]byte)
if !ok {
return 0, errors.New("invalid ByteArray item")
}
decimals = bigint.FromBytes(data).Int64()
2020-03-06 11:56:55 +00:00
default:
return 0, fmt.Errorf("invalid stack item type: %s", typ)
}
return decimals, nil
}
func topStringFromStack(st []smartcontract.Parameter) (string, error) {
index := len(st) - 1 // top stack element is last in the array
var s string
switch typ := st[index].Type; typ {
case smartcontract.StringType:
var ok bool
s, ok = st[index].Value.(string)
if !ok {
return "", errors.New("invalid String item")
}
case smartcontract.ByteArrayType:
data, ok := st[index].Value.([]byte)
if !ok {
return "", errors.New("invalid ByteArray item")
}
s = string(data)
default:
return "", fmt.Errorf("invalid stack item type: %s", typ)
}
return s, nil
}