From 80633402c2b891744d62c03045d00135853606e7 Mon Sep 17 00:00:00 2001
From: Anton Novojilov <andy@essentialkaos.com>
Date: Tue, 8 Dec 2020 16:43:10 +0300
Subject: [PATCH] Fix bug with proxying requests to GitHub

---
 common/pkgre.spec         |  5 ++++-
 server/morpher/morpher.go | 22 +++++++++++++++++-----
 server/server.go          |  2 +-
 3 files changed, 22 insertions(+), 7 deletions(-)

diff --git a/common/pkgre.spec b/common/pkgre.spec
index 1637f52..2247406 100644
--- a/common/pkgre.spec
+++ b/common/pkgre.spec
@@ -54,7 +54,7 @@
 
 Summary:            pkg.re morpher server
 Name:               pkgre
-Version:            4.0.0
+Version:            4.1.0
 Release:            0%{?dist}
 Group:              Applications/System
 License:            Apache License, Version 2.0
@@ -153,6 +153,9 @@ rm -rf %{buildroot}
 ################################################################################
 
 %changelog
+* Tue Dec 08 2020 Anton Novojilov <andy@essentialkaos.com> - 4.1.0-0
+- Fixed bug with proxying requests to GitHub
+
 * Thu Nov 12 2020 Anton Novojilov <andy@essentialkaos.com> - 4.0.0-0
 - Proxying all requests due to problems with Go Modules Services
 - ek package updated to v12
diff --git a/server/morpher/morpher.go b/server/morpher/morpher.go
index 9d67899..dfa7c55 100644
--- a/server/morpher/morpher.go
+++ b/server/morpher/morpher.go
@@ -8,6 +8,7 @@ package morpher
 // ////////////////////////////////////////////////////////////////////////////////// //
 
 import (
+	"bytes"
 	"errors"
 	"fmt"
 	"net/http"
@@ -62,6 +63,13 @@ type Metrics struct {
 
 // ////////////////////////////////////////////////////////////////////////////////// //
 
+var (
+	UAGit = []byte("git/")            // Git User-Agent
+	UAGo  = []byte("Go-http-client/") // Go User-Agent
+)
+
+// ////////////////////////////////////////////////////////////////////////////////// //
+
 // majorVerRegExp regexp for extracting major version
 var majorVerRegExp = regexp.MustCompile(`^[a-zA-Z]{0,}([0-9]{1}.*)`)
 
@@ -187,15 +195,19 @@ func requestHandler(ctx *fasthttp.RequestCtx) {
 		return
 	}
 
-	atomic.AddUint64(&metrics.Redirects, 1)
-
-	// Redirect to github
 	appendProcHeader(ctx, start)
 
 	url := repoInfo.GitHubURL(pkgInfo.TargetName)
 
-	log.Debug("Proxying request to %s", url)
-	proxyRequest(ctx, url)
+	// Proxy only requests from Go and Git
+	if bytes.HasPrefix(ctx.UserAgent(), UAGit) || bytes.HasPrefix(ctx.UserAgent(), UAGo) {
+		log.Debug("Proxying request to %s", url)
+		proxyRequest(ctx, url)
+	} else {
+		atomic.AddUint64(&metrics.Redirects, 1)
+		log.Debug("Redirecting request to %s", url)
+		redirectRequest(ctx, url)
+	}
 }
 
 // processBasicRequest redirect requests from main page to page defined in config
diff --git a/server/server.go b/server/server.go
index 1858916..5b7ff22 100644
--- a/server/server.go
+++ b/server/server.go
@@ -31,7 +31,7 @@ import (
 // Application info
 const (
 	APP  = "PkgRE Morpher Server"
-	VER  = "4.0.0"
+	VER  = "4.1.0"
 	DESC = "HTTP Server for morphing go get requests"
 )