2 files changed, 122 insertions, 0 deletions
diff --git a/cmd/go-import-redirect/main.go b/cmd/go-import-redirect/main.go
new file mode 100644
index 0000000..064e932
--- /dev/null
+++ b/cmd/go-import-redirect/main.go
@@ -0,0 +1,83 @@
+// Copyright (c) 2019, Grégoire Duchêne <gduchene@awhk.org>
+//
+// Use of this source code is governed by the ISC license that can be
+// found in the LICENSE file.
+
+// +build !aws
+
+package main
+
+import (
+	"context"
+	"log"
+	"net"
+	"net/http"
+	"os"
+	"os/signal"
+	"path"
+	"syscall"
+	"time"
+
+	"go.awhk.org/go-import-redirect/internal"
+)
+
+func redirect(resp http.ResponseWriter, req *http.Request) {
+	if req.Method != "GET" {
+		resp.Header()["Allow"] = []string{"GET"}
+		resp.WriteHeader(http.StatusMethodNotAllowed)
+		return
+	}
+
+	pkg := path.Join(req.Host, req.URL.Path)
+	resp.Header()["Content-Type"] = []string{"text/html; charset=utf-8"}
+	if v, ok := req.URL.Query()["go-get"]; ok && len(v) > 0 && v[0] == "1" {
+		resp.WriteHeader(http.StatusOK)
+	} else {
+		resp.Header()["Location"] = []string{"https://godoc.org/" + pkg}
+		resp.WriteHeader(http.StatusFound)
+	}
+	resp.Write([]byte(internal.GetBody(pkg)))
+}
+
+func main() {
+	mux := http.NewServeMux()
+	mux.HandleFunc("/", redirect)
+	srv := http.Server{Handler: mux}
+
+	done := make(chan os.Signal, 1)
+	signal.Notify(done, os.Interrupt, syscall.SIGINT, syscall.SIGTERM)
+
+	go func() {
+		var (
+			addr = os.Getenv("ADDR")
+			l    net.Listener
+			err  error
+		)
+		if addr != "" && addr[0] == '/' {
+			if l, err = net.Listen("unix", addr); err != nil {
+				log.Fatalln("net.Listen:", err)
+			}
+			// We do not do any authorization anyway, so 0666 makes sense here.
+			if err = os.Chmod(addr, 0666); err != nil {
+				log.Fatalln("os.Chmod:", err)
+			}
+		} else {
+			if addr == "" {
+				addr = ":8080"
+			}
+			if l, err = net.Listen("tcp", addr); err != nil {
+				log.Fatalln("net.Listen:", err)
+			}
+		}
+		if err = srv.Serve(l); err != nil && err != http.ErrServerClosed {
+			log.Fatalln("server.ListenAndServe:", err)
+		}
+	}()
+
+	<-done
+	ctx, cancel := context.WithTimeout(context.Background(), time.Second)
+	defer cancel()
+	if err := srv.Shutdown(ctx); err != nil && err != http.ErrServerClosed {
+		log.Fatalln("server.Shutdown:", err)
+	}
+}
diff --git a/cmd/go-import-redirect/main_aws.go b/cmd/go-import-redirect/main_aws.go
new file mode 100644
index 0000000..f6a95b1
--- /dev/null
+++ b/cmd/go-import-redirect/main_aws.go
@@ -0,0 +1,39 @@
+// Copyright (c) 2019, Grégoire Duchêne <gduchene@awhk.org>
+//
+// Use of this source code is governed by the ISC license that can be
+// found in the LICENSE file.
+
+// +build aws,linux
+
+package main
+
+import (
+	"context"
+	"net/http"
+	"path"
+
+	"github.com/aws/aws-lambda-go/events"
+	"github.com/aws/aws-lambda-go/lambda"
+	"go.awhk.org/go-import-redirect/internal"
+)
+
+func redirect(ctx context.Context, req events.APIGatewayProxyRequest) (events.APIGatewayProxyResponse, error) {
+	var (
+		pkg  = path.Join(req.Headers["Host"], req.Path)
+		resp = events.APIGatewayProxyResponse{
+			Body:    internal.GetBody(pkg),
+			Headers: map[string]string{"Content-Type": "text/html; charset=utf-8"},
+		}
+	)
+	if v, ok := req.QueryStringParameters["go-get"]; ok && v == "1" {
+		resp.StatusCode = http.StatusOK
+	} else {
+		resp.Headers["Location"] = "https://godoc.org/" + pkg
+		resp.StatusCode = http.StatusFound
+	}
+	return resp, nil
+}
+
+func main() {
+	lambda.Start(redirect)
+}