Adding upstream version 1.34.4.

Signed-off-by: Daniel Baumann <daniel@debian.org>

plugins/common/proxy/proxy.go

@@ -0,0 +1,57 @@
+package proxy
+
+import (
+	"fmt"
+	"net/http"
+	"net/url"
+
+	"golang.org/x/net/proxy"
+)
+
+type HTTPProxy struct {
+	UseSystemProxy bool   `toml:"use_system_proxy"`
+	HTTPProxyURL   string `toml:"http_proxy_url"`
+}
+
+type proxyFunc func(req *http.Request) (*url.URL, error)
+
+func (p *HTTPProxy) Proxy() (proxyFunc, error) {
+	if p.UseSystemProxy {
+		return http.ProxyFromEnvironment, nil
+	} else if len(p.HTTPProxyURL) > 0 {
+		address, err := url.Parse(p.HTTPProxyURL)
+		if err != nil {
+			return nil, fmt.Errorf("error parsing proxy url %q: %w", p.HTTPProxyURL, err)
+		}
+		return http.ProxyURL(address), nil
+	}
+
+	return nil, nil
+}
+
+type TCPProxy struct {
+	UseProxy bool   `toml:"use_proxy"`
+	ProxyURL string `toml:"proxy_url"`
+}
+
+func (p *TCPProxy) Proxy() (*ProxiedDialer, error) {
+	var dialer proxy.Dialer
+	if p.UseProxy {
+		if len(p.ProxyURL) > 0 {
+			parsed, err := url.Parse(p.ProxyURL)
+			if err != nil {
+				return nil, fmt.Errorf("error parsing proxy url %q: %w", p.ProxyURL, err)
+			}
+
+			if dialer, err = proxy.FromURL(parsed, proxy.Direct); err != nil {
+				return nil, err
+			}
+		} else {
+			dialer = proxy.FromEnvironment()
+		}
+	} else {
+		dialer = proxy.Direct
+	}
+
+	return &ProxiedDialer{dialer}, nil
+}