bsc/rpc/client_context_go1.6.go
Felix Lange 91b7690428 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.
2016-07-22 23:21:27 +02:00

56 lines
1.9 KiB
Go

// 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/>.
// +build go1.6,!go1.7
package rpc
import (
"net"
"net/http"
"time"
"golang.org/x/net/context"
)
// In Go 1.6, net.Dialer gained the ability to cancel via a channel.
// contextDialer returns a dialer that applies the deadline value from the given context.
func contextDialer(ctx context.Context) *net.Dialer {
dialer := &net.Dialer{Cancel: ctx.Done(), KeepAlive: tcpKeepAliveInterval}
if deadline, ok := ctx.Deadline(); ok {
dialer.Deadline = deadline
} else {
dialer.Deadline = time.Now().Add(defaultDialTimeout)
}
return dialer
}
// dialContext connects to the given address, aborting the dial if ctx is canceled.
func dialContext(ctx context.Context, network, addr string) (net.Conn, error) {
return contextDialer(ctx).Dial(network, addr)
}
// requestWithContext copies req, adding the cancelation channel and deadline from ctx.
func requestWithContext(c *http.Client, req *http.Request, ctx context.Context) (*http.Client, *http.Request) {
// We set Timeout on the client for Go <= 1.5. There
// is no need to do that here because the dial will be canceled
// by package http.
req2 := *req
req2.Cancel = ctx.Done()
return c, &req2
}