62 lines
		
	
	
		
			2.2 KiB
		
	
	
	
		
			Go
		
	
	
	
	
	
		
		
			
		
	
	
			62 lines
		
	
	
		
			2.2 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 go1.5,!go1.6 | ||
|  | 
 | ||
|  | package rpc | ||
|  | 
 | ||
|  | import ( | ||
|  | 	"net" | ||
|  | 	"net/http" | ||
|  | 	"time" | ||
|  | 
 | ||
|  | 	"golang.org/x/net/context" | ||
|  | ) | ||
|  | 
 | ||
|  | // In Go 1.5, dials cannot be canceled via a channel or context. The context deadline can | ||
|  | // still be applied. Go 1.5 adds the ability to cancel HTTP requests 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{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) { | ||
|  | 	// Set Timeout on the client if the context has a deadline. | ||
|  | 	// Note that there is no default timeout (unlike in contextDialer) because | ||
|  | 	// the timeout applies to the entire request, including reads from body. | ||
|  | 	if deadline, ok := ctx.Deadline(); ok { | ||
|  | 		c2 := *c | ||
|  | 		c2.Timeout = deadline.Sub(time.Now()) | ||
|  | 		c = &c2 | ||
|  | 	} | ||
|  | 	req2 := *req | ||
|  | 	req2.Cancel = ctx.Done() | ||
|  | 	return c, &req2 | ||
|  | } |