k3s/vendor/github.com/docker/go-connections/sockets/proxy.go

52 lines
1.1 KiB
Go

package sockets
import (
"net"
"net/url"
"os"
"strings"
"golang.org/x/net/proxy"
)
// GetProxyEnv allows access to the uppercase and the lowercase forms of
// proxy-related variables. See the Go specification for details on these
// variables. https://golang.org/pkg/net/http/
func GetProxyEnv(key string) string {
proxyValue := os.Getenv(strings.ToUpper(key))
if proxyValue == "" {
return os.Getenv(strings.ToLower(key))
}
return proxyValue
}
// DialerFromEnvironment takes in a "direct" *net.Dialer and returns a
// proxy.Dialer which will route the connections through the proxy using the
// given dialer.
func DialerFromEnvironment(direct *net.Dialer) (proxy.Dialer, error) {
allProxy := GetProxyEnv("all_proxy")
if len(allProxy) == 0 {
return direct, nil
}
proxyURL, err := url.Parse(allProxy)
if err != nil {
return direct, err
}
proxyFromURL, err := proxy.FromURL(proxyURL, direct)
if err != nil {
return direct, err
}
noProxy := GetProxyEnv("no_proxy")
if len(noProxy) == 0 {
return proxyFromURL, nil
}
perHost := proxy.NewPerHost(proxyFromURL, direct)
perHost.AddFromString(noProxy)
return perHost, nil
}