Support separate S3 serving endpoint (#91)

* Add s3 serving endpoint config. Fixes #90

* Move CDN endpoint generation to GenerateRemotePlaylist

* Include HLS path

* Add docs and config

* Prefer sprintf to string concatenation

* Use config method

* gofmt

core/storageproviders/s3Storage.go

@@ -2,6 +2,7 @@ package storageproviders
 
 import (
 	"bufio"
+	"fmt"
 	"os"
 	"strings"
 
@@ -21,12 +22,13 @@ type S3Storage struct {
 	sess *session.Session
 	host string
 
-	s3Endpoint  string
-	s3Region    string
-	s3Bucket    string
-	s3AccessKey string
-	s3Secret    string
-	s3ACL       string
+	s3Endpoint        string
+	s3ServingEndpoint string
+	s3Region          string
+	s3Bucket          string
+	s3AccessKey       string
+	s3Secret          string
+ 	s3ACL             string
 }
 
 //Setup sets up the s3 storage for saving the video to s3
@@ -34,6 +36,7 @@ func (s *S3Storage) Setup() error {
 	log.Trace("Setting up S3 for external storage of video...")
 
 	s.s3Endpoint = config.Config.S3.Endpoint
+	s.s3ServingEndpoint = config.Config.S3.ServingEndpoint
 	s.s3Region = config.Config.S3.Region
 	s.s3Bucket = config.Config.S3.Bucket
 	s.s3AccessKey = config.Config.S3.AccessKey
@@ -90,6 +93,8 @@ func (s *S3Storage) GenerateRemotePlaylist(playlist string, variant models.Varia
 			fullRemotePath := variant.GetSegmentForFilename(line)
 			if fullRemotePath == nil {
 				line = ""
+			} else if s.s3ServingEndpoint != "" {
+				line = fmt.Sprintf("%s/%s/%s", s.s3ServingEndpoint, config.Config.GetPrivateHLSSavePath(), fullRemotePath.RelativeUploadPath)
 			} else {
 				line = fullRemotePath.RemoteID
 			}