feat: add global proxy config

common/utils/tgutil/net.go

@@ -0,0 +1,41 @@
+package tgutil
+
+import (
+	"net/url"
+
+	"github.com/gotd/td/telegram/dcs"
+	"github.com/krau/SaveAny-Bot/config"
+	"golang.org/x/net/proxy"
+)
+
+func newProxyDialer(proxyUrl string) (proxy.Dialer, error) {
+	url, err := url.Parse(proxyUrl)
+	if err != nil {
+		return nil, err
+	}
+	return proxy.FromURL(url, proxy.Direct)
+}
+
+func NewConfigProxyResolver() (dcs.Resolver, error) {
+	resolver := dcs.DefaultResolver()
+	if config.C().Proxy != "" {
+		// gloabl proxy, which has lower priority
+		dialer, err := newProxyDialer(config.C().Proxy)
+		if err != nil {
+			return nil, err
+		}
+		resolver = dcs.Plain(dcs.PlainOptions{
+			Dial: dialer.(proxy.ContextDialer).DialContext,
+		})
+	}
+	if config.C().Telegram.Proxy.Enable && config.C().Telegram.Proxy.URL != "" {
+		dialer, err := newProxyDialer(config.C().Telegram.Proxy.URL)
+		if err != nil {
+			return nil, err
+		}
+		resolver = dcs.Plain(dcs.PlainOptions{
+			Dial: dialer.(proxy.ContextDialer).DialContext,
+		})
+	}
+	return resolver, nil
+}