proxy: add http/socks5 support, use for Jellyfin

can be found in advanced. Currently only used for the main Jellyfin
client.

easyproxy/easyproxy.go

@@ -0,0 +1,42 @@
+// Package easyproxy provides a method to quickly create a http.Transport using given proxy details (SOCKS5 or HTTP).
+package easyproxy
+
+import (
+	"net/http"
+	"net/url"
+
+	"golang.org/x/net/proxy"
+)
+
+type Protocol int
+
+const (
+	SOCKS5 Protocol = iota // SOCKS5
+	HTTP                   // HTTP
+)
+
+// NewTransport returns a http.Transport using the given proxy details. Leave user/pass blank if not needed.
+func NewTransport(p Protocol, addr, user, pass string) (*http.Transport, error) {
+	t := &http.Transport{}
+	if p == HTTP {
+		u := &url.URL{
+			Scheme: "http",
+			Host:   addr,
+		}
+		if user != "" && pass != "" {
+			u.User = url.UserPassword(user, pass)
+		}
+		t.Proxy = http.ProxyURL(u)
+		return t, nil
+	}
+	var auth *proxy.Auth = nil
+	if user != "" && pass != "" {
+		auth = &proxy.Auth{User: user, Password: pass}
+	}
+	dialer, err := proxy.SOCKS5("tcp", addr, auth, proxy.Direct)
+	if err != nil {
+		return nil, nil
+	}
+	t.Dial = dialer.Dial
+	return t, nil
+}

easyproxy/go.mod

@@ -0,0 +1,5 @@
+module github.com/hrfee/jfa-go/easyproxy
+
+go 1.20
+
+require golang.org/x/net v0.15.0

easyproxy/go.sum

@@ -0,0 +1,2 @@
+golang.org/x/net v0.15.0 h1:ugBLEUaxABaB5AJqW9enI0ACdci2RUd4eP51NTBvuJ8=
+golang.org/x/net v0.15.0/go.mod h1:idbUs1IY1+zTqbi8yxTbhexhEEk5ur9LInksu6HrEpk=