1 files changed, 55 insertions, 0 deletions
diff --git a/main.go b/main.go
new file mode 100644
index 0000000..97a4b55
--- /dev/null
+++ b/main.go
@@ -0,0 +1,55 @@
+// 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.
+
+package main
+
+import (
+	"context"
+	"fmt"
+	"github.com/aws/aws-lambda-go/events"
+	"github.com/aws/aws-lambda-go/lambda"
+	"os"
+	"path"
+	"strings"
+)
+
+func getDest(dest, repo string) string {
+	dest = strings.TrimRight(dest, "/")
+	return fmt.Sprintf("%s/%s", dest, repo)
+}
+
+func getRepo(pkg, prefix string) string {
+	prefix = strings.TrimRight(prefix, "/")
+	path := strings.TrimLeft(strings.TrimPrefix(pkg, prefix), "/")
+	return strings.Split(path, "/")[0]
+}
+
+func redirect(ctx context.Context, req events.APIGatewayProxyRequest) (events.APIGatewayProxyResponse, error) {
+	var (
+		pkg  = path.Join(req.Headers["Host"], req.Path)
+		dest = getDest(os.Getenv("DEST"), getRepo(pkg, os.Getenv("PREFIX")))
+		doc  = fmt.Sprintf("https://godoc.org/%s", pkg)
+		vcs  = os.Getenv("VCS")
+		body = fmt.Sprintf(`<!doctype html>
+<meta name="go-import" content="%s %s %s">
+<title>go-import-redirect</title>
+`, pkg, vcs, dest)
+		resp = events.APIGatewayProxyResponse{
+			Body:    body,
+			Headers: map[string]string{"Content-Type": "text/html; charset=utf-8"},
+		}
+	)
+	if v, ok := req.QueryStringParameters["go-get"]; ok && v == "1" {
+		resp.StatusCode = 200
+	} else {
+		resp.Headers["Location"] = doc
+		resp.StatusCode = 302
+	}
+	return resp, nil
+}
+
+func main() {
+	lambda.Start(redirect)
+}