From 91b769042857f542b2792b23ec407e1c9bd4fe8d Mon Sep 17 00:00:00 2001 From: Felix Lange Date: Tue, 12 Jul 2016 17:47:15 +0200 Subject: rpc: add new client, use it everywhere The new client implementation supports concurrent requests, subscriptions and replaces the various ad hoc RPC clients throughout go-ethereum. --- accounts/abi/bind/backends/remote.go | 160 ++++------------------------------- 1 file changed, 18 insertions(+), 142 deletions(-) (limited to 'accounts/abi/bind') diff --git a/accounts/abi/bind/backends/remote.go b/accounts/abi/bind/backends/remote.go index 4793143e4..58edd791a 100644 --- a/accounts/abi/bind/backends/remote.go +++ b/accounts/abi/bind/backends/remote.go @@ -17,11 +17,7 @@ package backends import ( - "encoding/json" - "fmt" "math/big" - "sync" - "sync/atomic" "github.com/ethereum/go-ethereum/accounts/abi/bind" "github.com/ethereum/go-ethereum/common" @@ -37,119 +33,34 @@ var _ bind.ContractBackend = (*rpcBackend)(nil) // rpcBackend implements bind.ContractBackend, and acts as the data provider to // Ethereum contracts bound to Go structs. It uses an RPC connection to delegate // all its functionality. -// -// Note: The current implementation is a blocking one. This should be replaced -// by a proper async version when a real RPC client is created. type rpcBackend struct { - client rpc.Client // RPC client connection to interact with an API server - autoid uint32 // ID number to use for the next API request - lock sync.Mutex // Singleton access until we get to request multiplexing + client *rpc.Client // RPC client connection to interact with an API server } // NewRPCBackend creates a new binding backend to an RPC provider that can be // used to interact with remote contracts. -func NewRPCBackend(client rpc.Client) bind.ContractBackend { - return &rpcBackend{ - client: client, - } -} - -// request is a JSON RPC request package assembled internally from the client -// method calls. -type request struct { - JSONRPC string `json:"jsonrpc"` // Version of the JSON RPC protocol, always set to 2.0 - ID int `json:"id"` // Auto incrementing ID number for this request - Method string `json:"method"` // Remote procedure name to invoke on the server - Params []interface{} `json:"params"` // List of parameters to pass through (keep types simple) -} - -// response is a JSON RPC response package sent back from the API server. -type response struct { - JSONRPC string `json:"jsonrpc"` // Version of the JSON RPC protocol, always set to 2.0 - ID int `json:"id"` // Auto incrementing ID number for this request - Error *failure `json:"error"` // Any error returned by the remote side - Result json.RawMessage `json:"result"` // Whatever the remote side sends us in reply -} - -// failure is a JSON RPC response error field sent back from the API server. -type failure struct { - Code int `json:"code"` // JSON RPC error code associated with the failure - Message string `json:"message"` // Specific error message of the failure -} - -// request forwards an API request to the RPC server, and parses the response. -// -// This is currently painfully non-concurrent, but it will have to do until we -// find the time for niceties like this :P -func (b *rpcBackend) request(ctx context.Context, method string, params []interface{}) (json.RawMessage, error) { - b.lock.Lock() - defer b.lock.Unlock() - - if ctx == nil { - ctx = context.Background() - } - - // Ugly hack to serialize an empty list properly - if params == nil { - params = []interface{}{} - } - // Assemble the request object - reqID := int(atomic.AddUint32(&b.autoid, 1)) - req := &request{ - JSONRPC: "2.0", - ID: reqID, - Method: method, - Params: params, - } - if err := b.client.Send(req); err != nil { - return nil, err - } - res := new(response) - errc := make(chan error, 1) - go func() { - errc <- b.client.Recv(res) - }() - select { - case err := <-errc: - if err != nil { - return nil, err - } - case <-ctx.Done(): - return nil, ctx.Err() - } - if res.Error != nil { - if res.Error.Message == bind.ErrNoCode.Error() { - return nil, bind.ErrNoCode - } - return nil, fmt.Errorf("remote error: %s", res.Error.Message) - } - return res.Result, nil +func NewRPCBackend(client *rpc.Client) bind.ContractBackend { + return &rpcBackend{client: client} } // HasCode implements ContractVerifier.HasCode by retrieving any code associated // with the contract from the remote node, and checking its size. func (b *rpcBackend) HasCode(ctx context.Context, contract common.Address, pending bool) (bool, error) { - // Execute the RPC code retrieval block := "latest" if pending { block = "pending" } - res, err := b.request(ctx, "eth_getCode", []interface{}{contract.Hex(), block}) - if err != nil { - return false, err - } var hex string - if err := json.Unmarshal(res, &hex); err != nil { + err := b.client.CallContext(ctx, &hex, "eth_getCode", contract, block) + if err != nil { return false, err } - // Convert the response back to a Go byte slice and return return len(common.FromHex(hex)) > 0, nil } // ContractCall implements ContractCaller.ContractCall, delegating the execution of // a contract call to the remote node, returning the reply to for local processing. func (b *rpcBackend) ContractCall(ctx context.Context, contract common.Address, data []byte, pending bool) ([]byte, error) { - // Pack up the request into an RPC argument args := struct { To common.Address `json:"to"` Data string `json:"data"` @@ -157,63 +68,43 @@ func (b *rpcBackend) ContractCall(ctx context.Context, contract common.Address, To: contract, Data: common.ToHex(data), } - // Execute the RPC call and retrieve the response block := "latest" if pending { block = "pending" } - res, err := b.request(ctx, "eth_call", []interface{}{args, block}) - if err != nil { - return nil, err - } var hex string - if err := json.Unmarshal(res, &hex); err != nil { + err := b.client.CallContext(ctx, &hex, "eth_call", args, block) + if err != nil { return nil, err } - // Convert the response back to a Go byte slice and return return common.FromHex(hex), nil + } // PendingAccountNonce implements ContractTransactor.PendingAccountNonce, delegating // the current account nonce retrieval to the remote node. func (b *rpcBackend) PendingAccountNonce(ctx context.Context, account common.Address) (uint64, error) { - res, err := b.request(ctx, "eth_getTransactionCount", []interface{}{account.Hex(), "pending"}) + var hex rpc.HexNumber + err := b.client.CallContext(ctx, &hex, "eth_getTransactionCount", account.Hex(), "pending") if err != nil { return 0, err } - var hex string - if err := json.Unmarshal(res, &hex); err != nil { - return 0, err - } - nonce, ok := new(big.Int).SetString(hex, 0) - if !ok { - return 0, fmt.Errorf("invalid nonce hex: %s", hex) - } - return nonce.Uint64(), nil + return hex.Uint64(), nil } // SuggestGasPrice implements ContractTransactor.SuggestGasPrice, delegating the // gas price oracle request to the remote node. func (b *rpcBackend) SuggestGasPrice(ctx context.Context) (*big.Int, error) { - res, err := b.request(ctx, "eth_gasPrice", nil) - if err != nil { - return nil, err - } - var hex string - if err := json.Unmarshal(res, &hex); err != nil { + var hex rpc.HexNumber + if err := b.client.CallContext(ctx, &hex, "eth_gasPrice"); err != nil { return nil, err } - price, ok := new(big.Int).SetString(hex, 0) - if !ok { - return nil, fmt.Errorf("invalid price hex: %s", hex) - } - return price, nil + return (*big.Int)(&hex), nil } // EstimateGasLimit implements ContractTransactor.EstimateGasLimit, delegating // the gas estimation to the remote node. func (b *rpcBackend) EstimateGasLimit(ctx context.Context, sender common.Address, contract *common.Address, value *big.Int, data []byte) (*big.Int, error) { - // Pack up the request into an RPC argument args := struct { From common.Address `json:"from"` To *common.Address `json:"to"` @@ -226,19 +117,12 @@ func (b *rpcBackend) EstimateGasLimit(ctx context.Context, sender common.Address Value: rpc.NewHexNumber(value), } // Execute the RPC call and retrieve the response - res, err := b.request(ctx, "eth_estimateGas", []interface{}{args}) + var hex rpc.HexNumber + err := b.client.CallContext(ctx, &hex, "eth_estimateGas", args) if err != nil { return nil, err } - var hex string - if err := json.Unmarshal(res, &hex); err != nil { - return nil, err - } - estimate, ok := new(big.Int).SetString(hex, 0) - if !ok { - return nil, fmt.Errorf("invalid estimate hex: %s", hex) - } - return estimate, nil + return (*big.Int)(&hex), nil } // SendTransaction implements ContractTransactor.SendTransaction, delegating the @@ -248,13 +132,5 @@ func (b *rpcBackend) SendTransaction(ctx context.Context, tx *types.Transaction) if err != nil { return err } - res, err := b.request(ctx, "eth_sendRawTransaction", []interface{}{common.ToHex(data)}) - if err != nil { - return err - } - var hex string - if err := json.Unmarshal(res, &hex); err != nil { - return err - } - return nil + return b.client.CallContext(ctx, nil, "eth_sendRawTransaction", common.ToHex(data)) } -- cgit