From f679cd3785f3c8109c1700c9b7a331c5fc1e3ffc Mon Sep 17 00:00:00 2001
From: Knut Ahlers <knut@ahlers.me>
Date: Mon, 13 May 2019 00:05:06 +0200
Subject: [PATCH] Force bootstrap to apply gzip encoding

Signed-off-by: Knut Ahlers <knut@ahlers.me>
---
 http.go   |  2 +-
 main.go   |  7 ++++---
 upload.go | 30 +++++++++++++++++++++++++-----
 3 files changed, 30 insertions(+), 9 deletions(-)

diff --git a/http.go b/http.go
index 7a9f0b5..88bafee 100644
--- a/http.go
+++ b/http.go
@@ -19,7 +19,7 @@ func simpleFilePost(res http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	url, err := executeUpload(fh.Filename, f, true, "")
+	url, err := executeUpload(fh.Filename, f, true, "", false)
 	if err != nil {
 		log.WithError(err).Error("Uploading file from HTTP request failed")
 		http.Error(res, "Failed to upload file. For details see the log.", http.StatusInternalServerError)
diff --git a/main.go b/main.go
index 25c05bb..5bfe926 100644
--- a/main.go
+++ b/main.go
@@ -9,8 +9,9 @@ import (
 	"io"
 	"os"
 
-	"github.com/Luzifer/rconfig"
 	log "github.com/sirupsen/logrus"
+
+	"github.com/Luzifer/rconfig"
 )
 
 var (
@@ -98,7 +99,7 @@ func doCLIUpload() error {
 		inFile = inFileHandle
 	}
 
-	url, err := executeUpload(inFileName, inFile, true, cfg.ContentType)
+	url, err := executeUpload(inFileName, inFile, true, cfg.ContentType, false)
 	if err != nil {
 		return fmt.Errorf("Unable to upload file: %s", err)
 	}
@@ -109,7 +110,7 @@ func doCLIUpload() error {
 
 func doBootstrap() error {
 	for _, asset := range []string{"index.html", "app.js"} {
-		if _, err := executeUpload(asset, bytes.NewReader(MustAsset("frontend/"+asset)), false, ""); err != nil {
+		if _, err := executeUpload(asset, bytes.NewReader(MustAsset("frontend/"+asset)), false, "", true); err != nil {
 			return fmt.Errorf("Unable to upload bootstrap asset %q: %s", asset, err)
 		}
 	}
diff --git a/upload.go b/upload.go
index bc1fab7..5207975 100644
--- a/upload.go
+++ b/upload.go
@@ -2,6 +2,7 @@ package main
 
 import (
 	"bytes"
+	"compress/gzip"
 	"crypto/sha1"
 	"fmt"
 	"html/template"
@@ -16,10 +17,11 @@ import (
 	"github.com/aws/aws-sdk-go/aws/session"
 	"github.com/aws/aws-sdk-go/service/s3"
 	"github.com/cheggaaa/pb"
+	"github.com/pkg/errors"
 	log "github.com/sirupsen/logrus"
 )
 
-func executeUpload(inFileName string, inFileHandle io.ReadSeeker, useCalculatedFilename bool, overrideMimeType string) (string, error) {
+func executeUpload(inFileName string, inFileHandle io.ReadSeeker, useCalculatedFilename bool, overrideMimeType string, forceGzip bool) (string, error) {
 	var (
 		upFile = inFileName
 		err    error
@@ -42,6 +44,23 @@ func executeUpload(inFileName string, inFileHandle io.ReadSeeker, useCalculatedF
 
 	log.Debugf("Uploading file to %q with type %q", upFile, mimeType)
 
+	var contentEncoding *string
+	if forceGzip {
+		buf := new(bytes.Buffer)
+		gw := gzip.NewWriter(buf)
+
+		if _, err := io.Copy(gw, inFileHandle); err != nil {
+			return "", errors.Wrap(err, "Unable to compress file")
+		}
+
+		if err := gw.Close(); err != nil {
+			return "", errors.Wrap(err, "Unable to close gzip writer")
+		}
+
+		inFileHandle = bytes.NewReader(buf.Bytes())
+		contentEncoding = aws.String("gzip")
+	}
+
 	sess := session.Must(session.NewSession())
 	svc := s3.New(sess)
 
@@ -69,10 +88,11 @@ func executeUpload(inFileName string, inFileHandle io.ReadSeeker, useCalculatedF
 	}
 
 	if _, err := svc.PutObject(&s3.PutObjectInput{
-		Body:        ps,
-		Bucket:      aws.String(cfg.Bucket),
-		ContentType: aws.String(mimeType),
-		Key:         aws.String(upFile),
+		Body:            ps,
+		Bucket:          aws.String(cfg.Bucket),
+		ContentEncoding: contentEncoding,
+		ContentType:     aws.String(mimeType),
+		Key:             aws.String(upFile),
 	}); err != nil {
 		return "", err
 	}