Bump up github.com/sirupsen/logrus to 1.8.1 (#90)

vendor/golang.org/x/net/proxy/proxy.go

@@ -11,9 +11,11 @@ import (
 	"net"
 	"net/url"
 	"os"
+	"sync"
 )
 
 // A Dialer is a means to establish a connection.
+// Custom dialers should also implement ContextDialer.
 type Dialer interface {
 	// Dial connects to the given address via the proxy.
 	Dial(network, addr string) (c net.Conn, err error)
@@ -24,29 +26,38 @@ type Auth struct {
 	User, Password string
 }
 
-// FromEnvironment returns the dialer specified by the proxy related variables in
-// the environment.
+// FromEnvironment returns the dialer specified by the proxy-related
+// variables in the environment and makes underlying connections
+// directly.
 func FromEnvironment() Dialer {
-	allProxy := os.Getenv("all_proxy")
+	return FromEnvironmentUsing(Direct)
+}
+
+// FromEnvironmentUsing returns the dialer specify by the proxy-related
+// variables in the environment and makes underlying connections
+// using the provided forwarding Dialer (for instance, a *net.Dialer
+// with desired configuration).
+func FromEnvironmentUsing(forward Dialer) Dialer {
+	allProxy := allProxyEnv.Get()
 	if len(allProxy) == 0 {
-		return Direct
+		return forward
 	}
 
 	proxyURL, err := url.Parse(allProxy)
 	if err != nil {
-		return Direct
+		return forward
 	}
-	proxy, err := FromURL(proxyURL, Direct)
+	proxy, err := FromURL(proxyURL, forward)
 	if err != nil {
-		return Direct
+		return forward
 	}
 
-	noProxy := os.Getenv("no_proxy")
+	noProxy := noProxyEnv.Get()
 	if len(noProxy) == 0 {
 		return proxy
 	}
 
-	perHost := NewPerHost(proxy, Direct)
+	perHost := NewPerHost(proxy, forward)
 	perHost.AddFromString(noProxy)
 	return perHost
 }
@@ -78,8 +89,13 @@ func FromURL(u *url.URL, forward Dialer) (Dialer, error) {
 	}
 
 	switch u.Scheme {
-	case "socks5":
-		return SOCKS5("tcp", u.Host, auth, forward)
+	case "socks5", "socks5h":
+		addr := u.Hostname()
+		port := u.Port()
+		if port == "" {
+			port = "1080"
+		}
+		return SOCKS5("tcp", net.JoinHostPort(addr, port), auth, forward)
 	}
 
 	// If the scheme doesn't match any of the built-in schemes, see if it
@@ -92,3 +108,42 @@ func FromURL(u *url.URL, forward Dialer) (Dialer, error) {
 
 	return nil, errors.New("proxy: unknown scheme: " + u.Scheme)
 }
+
+var (
+	allProxyEnv = &envOnce{
+		names: []string{"ALL_PROXY", "all_proxy"},
+	}
+	noProxyEnv = &envOnce{
+		names: []string{"NO_PROXY", "no_proxy"},
+	}
+)
+
+// envOnce looks up an environment variable (optionally by multiple
+// names) once. It mitigates expensive lookups on some platforms
+// (e.g. Windows).
+// (Borrowed from net/http/transport.go)
+type envOnce struct {
+	names []string
+	once  sync.Once
+	val   string
+}
+
+func (e *envOnce) Get() string {
+	e.once.Do(e.init)
+	return e.val
+}
+
+func (e *envOnce) init() {
+	for _, n := range e.names {
+		e.val = os.Getenv(n)
+		if e.val != "" {
+			return
+		}
+	}
+}
+
+// reset is used by tests
+func (e *envOnce) reset() {
+	e.once = sync.Once{}
+	e.val = ""
+}