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Diffstat (limited to 'ethclient/ethclient.go')
| -rw-r--r-- | ethclient/ethclient.go | 576 |
1 files changed, 576 insertions, 0 deletions
diff --git a/ethclient/ethclient.go b/ethclient/ethclient.go new file mode 100644 index 0000000..ed02182 --- /dev/null +++ b/ethclient/ethclient.go @@ -0,0 +1,576 @@ +// Copyright 2016 The go-ethereum Authors +// This file is part of the go-ethereum library. +// +// The go-ethereum library is free software: you can redistribute it and/or modify +// it under the terms of the GNU Lesser General Public License as published by +// the Free Software Foundation, either version 3 of the License, or +// (at your option) any later version. +// +// The go-ethereum library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU Lesser General Public License for more details. +// +// You should have received a copy of the GNU Lesser General Public License +// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>. + +// Package ethclient provides a client for the Ethereum RPC API. +package ethclient + +import ( + "context" + "encoding/json" + "errors" + "fmt" + "math/big" + + "github.com/ava-labs/avalanchego/ids" + "github.com/ava-labs/coreth" + "github.com/ava-labs/coreth/core/types" + "github.com/ava-labs/coreth/rpc" + "github.com/ethereum/go-ethereum/common" + "github.com/ethereum/go-ethereum/common/hexutil" + "github.com/ethereum/go-ethereum/rlp" +) + +// Client defines typed wrappers for the Ethereum RPC API. +type Client struct { + c *rpc.Client +} + +// Dial connects a client to the given URL. +func Dial(rawurl string) (*Client, error) { + return DialContext(context.Background(), rawurl) +} + +func DialContext(ctx context.Context, rawurl string) (*Client, error) { + c, err := rpc.DialContext(ctx, rawurl) + if err != nil { + return nil, err + } + return NewClient(c), nil +} + +// NewClient creates a client that uses the given RPC client. +func NewClient(c *rpc.Client) *Client { + return &Client{c} +} + +func (ec *Client) Close() { + ec.c.Close() +} + +// Blockchain Access + +// ChainId retrieves the current chain ID for transaction replay protection. +func (ec *Client) ChainID(ctx context.Context) (*big.Int, error) { + var result hexutil.Big + err := ec.c.CallContext(ctx, &result, "eth_chainId") + if err != nil { + return nil, err + } + return (*big.Int)(&result), err +} + +// BlockByHash returns the given full block. +// +// Note that loading full blocks requires two requests. Use HeaderByHash +// if you don't need all transactions or uncle headers. +func (ec *Client) BlockByHash(ctx context.Context, hash common.Hash) (*types.Block, error) { + return ec.getBlock(ctx, "eth_getBlockByHash", hash, true) +} + +// BlockByNumber returns a block from the current canonical chain. If number is nil, the +// latest known block is returned. +// +// Note that loading full blocks requires two requests. Use HeaderByNumber +// if you don't need all transactions or uncle headers. +func (ec *Client) BlockByNumber(ctx context.Context, number *big.Int) (*types.Block, error) { + return ec.getBlock(ctx, "eth_getBlockByNumber", toBlockNumArg(number), true) +} + +// BlockNumber returns the most recent block number +func (ec *Client) BlockNumber(ctx context.Context) (uint64, error) { + var result hexutil.Uint64 + err := ec.c.CallContext(ctx, &result, "eth_blockNumber") + return uint64(result), err +} + +type rpcBlock struct { + Hash common.Hash `json:"hash"` + Transactions []rpcTransaction `json:"transactions"` + UncleHashes []common.Hash `json:"uncles"` + Version uint32 `json:"version"` + ExtraData *[]byte `json:"blockExtraData"` +} + +func (ec *Client) getBlock(ctx context.Context, method string, args ...interface{}) (*types.Block, error) { + var raw json.RawMessage + err := ec.c.CallContext(ctx, &raw, method, args...) + if err != nil { + return nil, err + } else if len(raw) == 0 { + return nil, coreth.NotFound + } + // Decode header and transactions. + var head *types.Header + var body rpcBlock + if err := json.Unmarshal(raw, &head); err != nil { + return nil, err + } + if err := json.Unmarshal(raw, &body); err != nil { + return nil, err + } + // Quick-verify transaction and uncle lists. This mostly helps with debugging the server. + if head.UncleHash == types.EmptyUncleHash && len(body.UncleHashes) > 0 { + return nil, fmt.Errorf("server returned non-empty uncle list but block header indicates no uncles") + } + if head.UncleHash != types.EmptyUncleHash && len(body.UncleHashes) == 0 { + return nil, fmt.Errorf("server returned empty uncle list but block header indicates uncles") + } + if head.TxHash == types.EmptyRootHash && len(body.Transactions) > 0 { + return nil, fmt.Errorf("server returned non-empty transaction list but block header indicates no transactions") + } + if head.TxHash != types.EmptyRootHash && len(body.Transactions) == 0 { + return nil, fmt.Errorf("server returned empty transaction list but block header indicates transactions") + } + // Load uncles because they are not included in the block response. + var uncles []*types.Header + if len(body.UncleHashes) > 0 { + uncles = make([]*types.Header, len(body.UncleHashes)) + reqs := make([]rpc.BatchElem, len(body.UncleHashes)) + for i := range reqs { + reqs[i] = rpc.BatchElem{ + Method: "eth_getUncleByBlockHashAndIndex", + Args: []interface{}{body.Hash, hexutil.EncodeUint64(uint64(i))}, + Result: &uncles[i], + } + } + if err := ec.c.BatchCallContext(ctx, reqs); err != nil { + return nil, err + } + for i := range reqs { + if reqs[i].Error != nil { + return nil, reqs[i].Error + } + if uncles[i] == nil { + return nil, fmt.Errorf("got null header for uncle %d of block %x", i, body.Hash[:]) + } + } + } + // Fill the sender cache of transactions in the block. + txs := make([]*types.Transaction, len(body.Transactions)) + for i, tx := range body.Transactions { + if tx.From != nil { + setSenderFromServer(tx.tx, *tx.From, body.Hash) + } + txs[i] = tx.tx + } + return types.NewBlockWithHeader(head).WithBody(txs, uncles, body.Version, body.ExtraData), nil +} + +// HeaderByHash returns the block header with the given hash. +func (ec *Client) HeaderByHash(ctx context.Context, hash common.Hash) (*types.Header, error) { + var head *types.Header + err := ec.c.CallContext(ctx, &head, "eth_getBlockByHash", hash, false) + if err == nil && head == nil { + err = coreth.NotFound + } + return head, err +} + +// HeaderByNumber returns a block header from the current canonical chain. If number is +// nil, the latest known header is returned. +func (ec *Client) HeaderByNumber(ctx context.Context, number *big.Int) (*types.Header, error) { + var head *types.Header + err := ec.c.CallContext(ctx, &head, "eth_getBlockByNumber", toBlockNumArg(number), false) + if err == nil && head == nil { + err = coreth.NotFound + } + return head, err +} + +type rpcTransaction struct { + tx *types.Transaction + txExtraInfo +} + +type txExtraInfo struct { + BlockNumber *string `json:"blockNumber,omitempty"` + BlockHash *common.Hash `json:"blockHash,omitempty"` + From *common.Address `json:"from,omitempty"` +} + +func (tx *rpcTransaction) UnmarshalJSON(msg []byte) error { + if err := json.Unmarshal(msg, &tx.tx); err != nil { + return err + } + return json.Unmarshal(msg, &tx.txExtraInfo) +} + +// TransactionByHash returns the transaction with the given hash. +func (ec *Client) TransactionByHash(ctx context.Context, hash common.Hash) (tx *types.Transaction, isPending bool, err error) { + var json *rpcTransaction + err = ec.c.CallContext(ctx, &json, "eth_getTransactionByHash", hash) + if err != nil { + return nil, false, err + } else if json == nil { + return nil, false, coreth.NotFound + } else if _, r, _ := json.tx.RawSignatureValues(); r == nil { + return nil, false, fmt.Errorf("server returned transaction without signature") + } + if json.From != nil && json.BlockHash != nil { + setSenderFromServer(json.tx, *json.From, *json.BlockHash) + } + return json.tx, json.BlockNumber == nil, nil +} + +// TransactionSender returns the sender address of the given transaction. The transaction +// must be known to the remote node and included in the blockchain at the given block and +// index. The sender is the one derived by the protocol at the time of inclusion. +// +// There is a fast-path for transactions retrieved by TransactionByHash and +// TransactionInBlock. Getting their sender address can be done without an RPC interaction. +func (ec *Client) TransactionSender(ctx context.Context, tx *types.Transaction, block common.Hash, index uint) (common.Address, error) { + // Try to load the address from the cache. + sender, err := types.Sender(&senderFromServer{blockhash: block}, tx) + if err == nil { + return sender, nil + } + var meta struct { + Hash common.Hash + From common.Address + } + if err = ec.c.CallContext(ctx, &meta, "eth_getTransactionByBlockHashAndIndex", block, hexutil.Uint64(index)); err != nil { + return common.Address{}, err + } + if meta.Hash == (common.Hash{}) || meta.Hash != tx.Hash() { + return common.Address{}, errors.New("wrong inclusion block/index") + } + return meta.From, nil +} + +// TransactionCount returns the total number of transactions in the given block. +func (ec *Client) TransactionCount(ctx context.Context, blockHash common.Hash) (uint, error) { + var num hexutil.Uint + err := ec.c.CallContext(ctx, &num, "eth_getBlockTransactionCountByHash", blockHash) + return uint(num), err +} + +// TransactionInBlock returns a single transaction at index in the given block. +func (ec *Client) TransactionInBlock(ctx context.Context, blockHash common.Hash, index uint) (*types.Transaction, error) { + var json *rpcTransaction + err := ec.c.CallContext(ctx, &json, "eth_getTransactionByBlockHashAndIndex", blockHash, hexutil.Uint64(index)) + if err != nil { + return nil, err + } + if json == nil { + return nil, coreth.NotFound + } else if _, r, _ := json.tx.RawSignatureValues(); r == nil { + return nil, fmt.Errorf("server returned transaction without signature") + } + if json.From != nil && json.BlockHash != nil { + setSenderFromServer(json.tx, *json.From, *json.BlockHash) + } + return json.tx, err +} + +// TransactionReceipt returns the receipt of a transaction by transaction hash. +// Note that the receipt is not available for pending transactions. +func (ec *Client) TransactionReceipt(ctx context.Context, txHash common.Hash) (*types.Receipt, error) { + var r *types.Receipt + err := ec.c.CallContext(ctx, &r, "eth_getTransactionReceipt", txHash) + if err == nil { + if r == nil { + return nil, coreth.NotFound + } + } + return r, err +} + +func toBlockNumArg(number *big.Int) string { + // The Ethereum implementation uses a different mapping from + // negative numbers to special strings (latest, pending) then is + // used on its server side. See rpc/types.go for the comparison. + // if number == nil { + // return "latest" + // } + // pending := big.NewInt(-1) + // if number.Cmp(pending) == 0 { + // return "pending" + // } + + // In Coreth, latest, pending, and accepted are all treated the same + // therefore, if [number] is nil or a negative number in [-3, -1] + // we want the latest accepted block + if number == nil { + return "latest" + } + low := big.NewInt(-3) + high := big.NewInt(-1) + if number.Cmp(low) >= 0 && number.Cmp(high) <= 0 { + return "latest" + } + return hexutil.EncodeBig(number) +} + +type rpcProgress struct { + StartingBlock hexutil.Uint64 + CurrentBlock hexutil.Uint64 + HighestBlock hexutil.Uint64 + PulledStates hexutil.Uint64 + KnownStates hexutil.Uint64 +} + +// SyncProgress retrieves the current progress of the sync algorithm. If there's +// no sync currently running, it returns nil. +// eth_syncing is not implemented in Coreth +// func (ec *Client) SyncProgress(ctx context.Context) (*coreth.SyncProgress, error) { +// var raw json.RawMessage +// if err := ec.c.CallContext(ctx, &raw, "eth_syncing"); err != nil { +// return nil, err +// } +// // Handle the possible response types +// var syncing bool +// if err := json.Unmarshal(raw, &syncing); err == nil { +// return nil, nil // Not syncing (always false) +// } +// var progress *rpcProgress +// if err := json.Unmarshal(raw, &progress); err != nil { +// return nil, err +// } +// return &coreth.SyncProgress{ +// StartingBlock: uint64(progress.StartingBlock), +// CurrentBlock: uint64(progress.CurrentBlock), +// HighestBlock: uint64(progress.HighestBlock), +// PulledStates: uint64(progress.PulledStates), +// KnownStates: uint64(progress.KnownStates), +// }, nil +// } + +// SubscribeNewHead subscribes to notifications about the current blockchain head +// on the given channel. +func (ec *Client) SubscribeNewHead(ctx context.Context, ch chan<- *types.Header) (coreth.Subscription, error) { + return ec.c.EthSubscribe(ctx, ch, "newHeads") +} + +// State Access + +// NetworkID returns the network ID (also known as the chain ID) for this chain. +func (ec *Client) NetworkID(ctx context.Context) (*big.Int, error) { + version := new(big.Int) + var ver string + if err := ec.c.CallContext(ctx, &ver, "net_version"); err != nil { + return nil, err + } + if _, ok := version.SetString(ver, 10); !ok { + return nil, fmt.Errorf("invalid net_version result %q", ver) + } + return version, nil +} + +// BalanceAt returns the wei balance of the given account. +// The block number can be nil, in which case the balance is taken from the latest known block. +func (ec *Client) BalanceAt(ctx context.Context, account common.Address, blockNumber *big.Int) (*big.Int, error) { + var result hexutil.Big + err := ec.c.CallContext(ctx, &result, "eth_getBalance", account, toBlockNumArg(blockNumber)) + return (*big.Int)(&result), err +} + +// AssetBalanceAt returns the [assetID] balance of the given account +// The block number can be nil, in which case the balance is taken from the latest known block. +func (ec *Client) AssetBalanceAt(ctx context.Context, account common.Address, assetID ids.ID, blockNumber *big.Int) (*big.Int, error) { + var result hexutil.Big + err := ec.c.CallContext(ctx, &result, "eth_getBalance", account, toBlockNumArg(blockNumber), assetID) + return (*big.Int)(&result), err +} + +// StorageAt returns the value of key in the contract storage of the given account. +// The block number can be nil, in which case the value is taken from the latest known block. +func (ec *Client) StorageAt(ctx context.Context, account common.Address, key common.Hash, blockNumber *big.Int) ([]byte, error) { + var result hexutil.Bytes + err := ec.c.CallContext(ctx, &result, "eth_getStorageAt", account, key, toBlockNumArg(blockNumber)) + return result, err +} + +// CodeAt returns the contract code of the given account. +// The block number can be nil, in which case the code is taken from the latest known block. +func (ec *Client) CodeAt(ctx context.Context, account common.Address, blockNumber *big.Int) ([]byte, error) { + var result hexutil.Bytes + err := ec.c.CallContext(ctx, &result, "eth_getCode", account, toBlockNumArg(blockNumber)) + return result, err +} + +// NonceAt returns the account nonce of the given account. +// The block number can be nil, in which case the nonce is taken from the latest known block. +func (ec *Client) NonceAt(ctx context.Context, account common.Address, blockNumber *big.Int) (uint64, error) { + var result hexutil.Uint64 + err := ec.c.CallContext(ctx, &result, "eth_getTransactionCount", account, toBlockNumArg(blockNumber)) + return uint64(result), err +} + +// Filters + +// FilterLogs executes a filter query. +func (ec *Client) FilterLogs(ctx context.Context, q coreth.FilterQuery) ([]types.Log, error) { + var result []types.Log + arg, err := toFilterArg(q) + if err != nil { + return nil, err + } + err = ec.c.CallContext(ctx, &result, "eth_getLogs", arg) + return result, err +} + +// SubscribeFilterLogs subscribes to the results of a streaming filter query. +func (ec *Client) SubscribeFilterLogs(ctx context.Context, q coreth.FilterQuery, ch chan<- types.Log) (coreth.Subscription, error) { + arg, err := toFilterArg(q) + if err != nil { + return nil, err + } + return ec.c.EthSubscribe(ctx, ch, "logs", arg) +} + +func toFilterArg(q coreth.FilterQuery) (interface{}, error) { + arg := map[string]interface{}{ + "address": q.Addresses, + "topics": q.Topics, + } + if q.BlockHash != nil { + arg["blockHash"] = *q.BlockHash + if q.FromBlock != nil || q.ToBlock != nil { + return nil, fmt.Errorf("cannot specify both BlockHash and FromBlock/ToBlock") + } + } else { + if q.FromBlock == nil { + arg["fromBlock"] = "0x0" + } else { + arg["fromBlock"] = toBlockNumArg(q.FromBlock) + } + arg["toBlock"] = toBlockNumArg(q.ToBlock) + } + return arg, nil +} + +// Pending State is irrelevant in Coreth + +// // PendingBalanceAt returns the wei balance of the given account in the pending state. +// func (ec *Client) PendingBalanceAt(ctx context.Context, account common.Address) (*big.Int, error) { +// var result hexutil.Big +// err := ec.c.CallContext(ctx, &result, "eth_getBalance", account, "pending") +// return (*big.Int)(&result), err +// } + +// // PendingStorageAt returns the value of key in the contract storage of the given account in the pending state. +// func (ec *Client) PendingStorageAt(ctx context.Context, account common.Address, key common.Hash) ([]byte, error) { +// var result hexutil.Bytes +// err := ec.c.CallContext(ctx, &result, "eth_getStorageAt", account, key, "pending") +// return result, err +// } + +// // PendingCodeAt returns the contract code of the given account in the pending state. +// func (ec *Client) PendingCodeAt(ctx context.Context, account common.Address) ([]byte, error) { +// var result hexutil.Bytes +// err := ec.c.CallContext(ctx, &result, "eth_getCode", account, "pending") +// return result, err +// } + +// // PendingNonceAt returns the account nonce of the given account in the pending state. +// // This is the nonce that should be used for the next transaction. +// func (ec *Client) PendingNonceAt(ctx context.Context, account common.Address) (uint64, error) { +// var result hexutil.Uint64 +// err := ec.c.CallContext(ctx, &result, "eth_getTransactionCount", account, "pending") +// return uint64(result), err +// } + +// // PendingTransactionCount returns the total number of transactions in the pending state. +// func (ec *Client) PendingTransactionCount(ctx context.Context) (uint, error) { +// var num hexutil.Uint +// err := ec.c.CallContext(ctx, &num, "eth_getBlockTransactionCountByNumber", "pending") +// return uint(num), err +// } + +// TODO: SubscribePendingTransactions (needs server side) + +// Contract Calling + +// CallContract executes a message call transaction, which is directly executed in the VM +// of the node, but never mined into the blockchain. +// +// blockNumber selects the block height at which the call runs. It can be nil, in which +// case the code is taken from the latest known block. Note that state from very old +// blocks might not be available. +func (ec *Client) CallContract(ctx context.Context, msg coreth.CallMsg, blockNumber *big.Int) ([]byte, error) { + var hex hexutil.Bytes + err := ec.c.CallContext(ctx, &hex, "eth_call", toCallArg(msg), toBlockNumArg(blockNumber)) + if err != nil { + return nil, err + } + return hex, nil +} + +// // PendingCallContract executes a message call transaction using the EVM. +// // The state seen by the contract call is the pending state. +// func (ec *Client) PendingCallContract(ctx context.Context, msg coreth.CallMsg) ([]byte, error) { +// var hex hexutil.Bytes +// err := ec.c.CallContext(ctx, &hex, "eth_call", toCallArg(msg), "pending") +// if err != nil { +// return nil, err +// } +// return hex, nil +// } + +// SuggestGasPrice retrieves the currently suggested gas price to allow a timely +// execution of a transaction. +func (ec *Client) SuggestGasPrice(ctx context.Context) (*big.Int, error) { + var hex hexutil.Big + if err := ec.c.CallContext(ctx, &hex, "eth_gasPrice"); err != nil { + return nil, err + } + return (*big.Int)(&hex), nil +} + +// EstimateGas tries to estimate the gas needed to execute a specific transaction based on +// the current pending state of the backend blockchain. There is no guarantee that this is +// the true gas limit requirement as other transactions may be added or removed by miners, +// but it should provide a basis for setting a reasonable default. +func (ec *Client) EstimateGas(ctx context.Context, msg coreth.CallMsg) (uint64, error) { + var hex hexutil.Uint64 + err := ec.c.CallContext(ctx, &hex, "eth_estimateGas", toCallArg(msg)) + if err != nil { + return 0, err + } + return uint64(hex), nil +} + +// SendTransaction injects a signed transaction into the pending pool for execution. +// +// If the transaction was a contract creation use the TransactionReceipt method to get the +// contract address after the transaction has been mined. +func (ec *Client) SendTransaction(ctx context.Context, tx *types.Transaction) error { + data, err := rlp.EncodeToBytes(tx) + if err != nil { + return err + } + return ec.c.CallContext(ctx, nil, "eth_sendRawTransaction", hexutil.Encode(data)) +} + +func toCallArg(msg coreth.CallMsg) interface{} { + arg := map[string]interface{}{ + "from": msg.From, + "to": msg.To, + } + if len(msg.Data) > 0 { + arg["data"] = hexutil.Bytes(msg.Data) + } + if msg.Value != nil { + arg["value"] = (*hexutil.Big)(msg.Value) + } + if msg.Gas != 0 { + arg["gas"] = hexutil.Uint64(msg.Gas) + } + if msg.GasPrice != nil { + arg["gasPrice"] = (*hexutil.Big)(msg.GasPrice) + } + return arg +} |