forked from TrueCloudLab/neoneo-go
317 lines
11 KiB
Go
317 lines
11 KiB
Go
/*
|
|
Package nep11 contains RPC wrappers for NEP-11 contracts.
|
|
|
|
The set of types provided is split between common NEP-11 methods (BaseReader and
|
|
Base types) and divisible (DivisibleReader and Divisible) and non-divisible
|
|
(NonDivisibleReader and NonDivisible). If you don't know the type of NEP-11
|
|
contract you're going to use you can use Base and BaseReader types for many
|
|
purposes, otherwise more specific types are recommended.
|
|
*/
|
|
package nep11
|
|
|
|
import (
|
|
"errors"
|
|
"fmt"
|
|
"math/big"
|
|
"unicode/utf8"
|
|
|
|
"github.com/google/uuid"
|
|
"github.com/nspcc-dev/neo-go/pkg/core/transaction"
|
|
"github.com/nspcc-dev/neo-go/pkg/neorpc/result"
|
|
"github.com/nspcc-dev/neo-go/pkg/rpcclient/neptoken"
|
|
"github.com/nspcc-dev/neo-go/pkg/rpcclient/unwrap"
|
|
"github.com/nspcc-dev/neo-go/pkg/smartcontract"
|
|
"github.com/nspcc-dev/neo-go/pkg/util"
|
|
"github.com/nspcc-dev/neo-go/pkg/vm/stackitem"
|
|
)
|
|
|
|
// Invoker is used by reader types to call various methods.
|
|
type Invoker interface {
|
|
neptoken.Invoker
|
|
|
|
CallAndExpandIterator(contract util.Uint160, method string, maxItems int, params ...any) (*result.Invoke, error)
|
|
TerminateSession(sessionID uuid.UUID) error
|
|
TraverseIterator(sessionID uuid.UUID, iterator *result.Iterator, num int) ([]stackitem.Item, error)
|
|
}
|
|
|
|
// Actor is used by complete NEP-11 types to create and send transactions.
|
|
type Actor interface {
|
|
Invoker
|
|
|
|
MakeRun(script []byte) (*transaction.Transaction, error)
|
|
MakeUnsignedRun(script []byte, attrs []transaction.Attribute) (*transaction.Transaction, error)
|
|
SendRun(script []byte) (util.Uint256, uint32, error)
|
|
}
|
|
|
|
// BaseReader is a reader interface for common divisible and non-divisible NEP-11
|
|
// methods. It allows to invoke safe methods.
|
|
type BaseReader struct {
|
|
neptoken.Base
|
|
|
|
invoker Invoker
|
|
hash util.Uint160
|
|
}
|
|
|
|
// BaseWriter is a transaction-creating interface for common divisible and
|
|
// non-divisible NEP-11 methods. It simplifies reusing this set of methods,
|
|
// but a complete Base is expected to be used in other packages.
|
|
type BaseWriter struct {
|
|
hash util.Uint160
|
|
actor Actor
|
|
}
|
|
|
|
// Base is a state-changing interface for common divisible and non-divisible NEP-11
|
|
// methods.
|
|
type Base struct {
|
|
BaseReader
|
|
BaseWriter
|
|
}
|
|
|
|
// TransferEvent represents a Transfer event as defined in the NEP-11 standard.
|
|
type TransferEvent struct {
|
|
From util.Uint160
|
|
To util.Uint160
|
|
Amount *big.Int
|
|
ID []byte
|
|
}
|
|
|
|
// TokenIterator is used for iterating over TokensOf results.
|
|
type TokenIterator struct {
|
|
client Invoker
|
|
session uuid.UUID
|
|
iterator result.Iterator
|
|
}
|
|
|
|
// NewBaseReader creates an instance of BaseReader for a contract with the given
|
|
// hash using the given invoker.
|
|
func NewBaseReader(invoker Invoker, hash util.Uint160) *BaseReader {
|
|
return &BaseReader{*neptoken.New(invoker, hash), invoker, hash}
|
|
}
|
|
|
|
// NewBase creates an instance of Base for contract with the given
|
|
// hash using the given actor.
|
|
func NewBase(actor Actor, hash util.Uint160) *Base {
|
|
return &Base{*NewBaseReader(actor, hash), BaseWriter{hash, actor}}
|
|
}
|
|
|
|
// Properties returns a set of token's properties such as name or URL. The map
|
|
// is returned as is from this method (stack item) for maximum flexibility,
|
|
// contracts can return a lot of specific data there. Most of the time though
|
|
// they return well-defined properties outlined in NEP-11 and
|
|
// UnwrapKnownProperties can be used to get them in more convenient way. It's an
|
|
// optional method per NEP-11 specification, so it can fail.
|
|
func (t *BaseReader) Properties(token []byte) (*stackitem.Map, error) {
|
|
return unwrap.Map(t.invoker.Call(t.hash, "properties", token))
|
|
}
|
|
|
|
// Tokens returns an iterator that allows to retrieve all tokens minted by the
|
|
// contract. It depends on the server to provide proper session-based
|
|
// iterator, but can also work with expanded one. The method itself is optional
|
|
// per NEP-11 specification, so it can fail.
|
|
func (t *BaseReader) Tokens() (*TokenIterator, error) {
|
|
sess, iter, err := unwrap.SessionIterator(t.invoker.Call(t.hash, "tokens"))
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return &TokenIterator{t.invoker, sess, iter}, nil
|
|
}
|
|
|
|
// TokensExpanded uses the same NEP-11 method as Tokens, but can be useful if
|
|
// the server used doesn't support sessions and doesn't expand iterators. It
|
|
// creates a script that will get num of result items from the iterator right in
|
|
// the VM and return them to you. It's only limited by VM stack and GAS available
|
|
// for RPC invocations.
|
|
func (t *BaseReader) TokensExpanded(num int) ([][]byte, error) {
|
|
return unwrap.ArrayOfBytes(t.invoker.CallAndExpandIterator(t.hash, "tokens", num))
|
|
}
|
|
|
|
// TokensOf returns an iterator that allows to walk through all tokens owned by
|
|
// the given account. It depends on the server to provide proper session-based
|
|
// iterator, but can also work with expanded one.
|
|
func (t *BaseReader) TokensOf(account util.Uint160) (*TokenIterator, error) {
|
|
sess, iter, err := unwrap.SessionIterator(t.invoker.Call(t.hash, "tokensOf", account))
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return &TokenIterator{t.invoker, sess, iter}, nil
|
|
}
|
|
|
|
// TokensOfExpanded uses the same NEP-11 method as TokensOf, but can be useful if
|
|
// the server used doesn't support sessions and doesn't expand iterators. It
|
|
// creates a script that will get num of result items from the iterator right in
|
|
// the VM and return them to you. It's only limited by VM stack and GAS available
|
|
// for RPC invocations.
|
|
func (t *BaseReader) TokensOfExpanded(account util.Uint160, num int) ([][]byte, error) {
|
|
return unwrap.ArrayOfBytes(t.invoker.CallAndExpandIterator(t.hash, "tokensOf", num, account))
|
|
}
|
|
|
|
// Transfer creates and sends a transaction that performs a `transfer` method
|
|
// call using the given parameters and checks for this call result, failing the
|
|
// transaction if it's not true. It works for divisible NFTs only when there is
|
|
// one owner for the particular token. The returned values are transaction hash,
|
|
// its ValidUntilBlock value and an error if any.
|
|
func (t *BaseWriter) Transfer(to util.Uint160, id []byte, data any) (util.Uint256, uint32, error) {
|
|
script, err := t.transferScript(to, id, data)
|
|
if err != nil {
|
|
return util.Uint256{}, 0, err
|
|
}
|
|
return t.actor.SendRun(script)
|
|
}
|
|
|
|
// TransferTransaction creates a transaction that performs a `transfer` method
|
|
// call using the given parameters and checks for this call result, failing the
|
|
// transaction if it's not true. It works for divisible NFTs only when there is
|
|
// one owner for the particular token. This transaction is signed, but not sent
|
|
// to the network, instead it's returned to the caller.
|
|
func (t *BaseWriter) TransferTransaction(to util.Uint160, id []byte, data any) (*transaction.Transaction, error) {
|
|
script, err := t.transferScript(to, id, data)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return t.actor.MakeRun(script)
|
|
}
|
|
|
|
// TransferUnsigned creates a transaction that performs a `transfer` method
|
|
// call using the given parameters and checks for this call result, failing the
|
|
// transaction if it's not true. It works for divisible NFTs only when there is
|
|
// one owner for the particular token. This transaction is not signed and just
|
|
// returned to the caller.
|
|
func (t *BaseWriter) TransferUnsigned(to util.Uint160, id []byte, data any) (*transaction.Transaction, error) {
|
|
script, err := t.transferScript(to, id, data)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
return t.actor.MakeUnsignedRun(script, nil)
|
|
}
|
|
|
|
func (t *BaseWriter) transferScript(params ...any) ([]byte, error) {
|
|
return smartcontract.CreateCallWithAssertScript(t.hash, "transfer", params...)
|
|
}
|
|
|
|
// Next returns the next set of elements from the iterator (up to num of them).
|
|
// It can return less than num elements in case iterator doesn't have that many
|
|
// or zero elements if the iterator has no more elements or the session is
|
|
// expired.
|
|
func (v *TokenIterator) Next(num int) ([][]byte, error) {
|
|
items, err := v.client.TraverseIterator(v.session, &v.iterator, num)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
res := make([][]byte, len(items))
|
|
for i := range items {
|
|
b, err := items[i].TryBytes()
|
|
if err != nil {
|
|
return nil, fmt.Errorf("element %d is not a byte string: %w", i, err)
|
|
}
|
|
res[i] = b
|
|
}
|
|
return res, nil
|
|
}
|
|
|
|
// Terminate closes the iterator session used by TokenIterator (if it's
|
|
// session-based).
|
|
func (v *TokenIterator) Terminate() error {
|
|
if v.iterator.ID == nil {
|
|
return nil
|
|
}
|
|
return v.client.TerminateSession(v.session)
|
|
}
|
|
|
|
// UnwrapKnownProperties can be used as a proxy function to extract well-known
|
|
// NEP-11 properties (name/description/image/tokenURI) defined in the standard.
|
|
// These properties are checked to be valid UTF-8 strings, but can contain
|
|
// control codes or special characters.
|
|
func UnwrapKnownProperties(m *stackitem.Map, err error) (map[string]string, error) {
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
elems := m.Value().([]stackitem.MapElement)
|
|
res := make(map[string]string)
|
|
for _, e := range elems {
|
|
k, err := e.Key.TryBytes()
|
|
if err != nil { // Shouldn't ever happen in the valid Map, but.
|
|
continue
|
|
}
|
|
ks := string(k)
|
|
if !result.KnownNEP11Properties[ks] { // Some additional elements are OK.
|
|
continue
|
|
}
|
|
v, err := e.Value.TryBytes()
|
|
if err != nil { // But known ones MUST be proper strings.
|
|
return nil, fmt.Errorf("invalid %s property: %w", ks, err)
|
|
}
|
|
if !utf8.Valid(v) {
|
|
return nil, fmt.Errorf("invalid %s property: not a UTF-8 string", ks)
|
|
}
|
|
res[ks] = string(v)
|
|
}
|
|
return res, nil
|
|
}
|
|
|
|
// TransferEventsFromApplicationLog retrieves all emitted TransferEvents from the
|
|
// provided [result.ApplicationLog].
|
|
func TransferEventsFromApplicationLog(log *result.ApplicationLog) ([]*TransferEvent, error) {
|
|
if log == nil {
|
|
return nil, errors.New("nil application log")
|
|
}
|
|
var res []*TransferEvent
|
|
for i, ex := range log.Executions {
|
|
for j, e := range ex.Events {
|
|
if e.Name != "Transfer" {
|
|
continue
|
|
}
|
|
event := new(TransferEvent)
|
|
err := event.FromStackItem(e.Item)
|
|
if err != nil {
|
|
return nil, fmt.Errorf("failed to decode event from stackitem (event #%d, execution #%d): %w", j, i, err)
|
|
}
|
|
res = append(res, event)
|
|
}
|
|
}
|
|
return res, nil
|
|
}
|
|
|
|
// FromStackItem converts provided [stackitem.Array] to TransferEvent or returns an
|
|
// error if it's not possible to do to so.
|
|
func (e *TransferEvent) FromStackItem(item *stackitem.Array) error {
|
|
if item == nil {
|
|
return errors.New("nil item")
|
|
}
|
|
arr, ok := item.Value().([]stackitem.Item)
|
|
if !ok {
|
|
return errors.New("not an array")
|
|
}
|
|
if len(arr) != 4 {
|
|
return errors.New("wrong number of event parameters")
|
|
}
|
|
|
|
b, err := arr[0].TryBytes()
|
|
if err != nil {
|
|
return fmt.Errorf("invalid From: %w", err)
|
|
}
|
|
e.From, err = util.Uint160DecodeBytesBE(b)
|
|
if err != nil {
|
|
return fmt.Errorf("failed to decode From: %w", err)
|
|
}
|
|
|
|
b, err = arr[1].TryBytes()
|
|
if err != nil {
|
|
return fmt.Errorf("invalid To: %w", err)
|
|
}
|
|
e.To, err = util.Uint160DecodeBytesBE(b)
|
|
if err != nil {
|
|
return fmt.Errorf("failed to decode To: %w", err)
|
|
}
|
|
|
|
e.Amount, err = arr[2].TryInteger()
|
|
if err != nil {
|
|
return fmt.Errorf("field to decode Avount: %w", err)
|
|
}
|
|
|
|
e.ID, err = arr[3].TryBytes()
|
|
if err != nil {
|
|
return fmt.Errorf("failed to decode ID: %w", err)
|
|
}
|
|
|
|
return nil
|
|
}
|