support unofficial S3 regions

Adds support for S3 clones like Ceph.

api/file.go

@@ -538,7 +538,7 @@ func writeFile(f []byte, path string) *model.AppError {
 		auth.AccessKey = utils.Cfg.FileSettings.AmazonS3AccessKeyId
 		auth.SecretKey = utils.Cfg.FileSettings.AmazonS3SecretAccessKey
 
-		s := s3.New(auth, aws.Regions[utils.Cfg.FileSettings.AmazonS3Region])
+		s := s3.New(auth, awsRegion())
 		bucket := s.Bucket(utils.Cfg.FileSettings.AmazonS3Bucket)
 
 		ext := filepath.Ext(path)
@@ -578,7 +578,7 @@ func readFile(path string) ([]byte, *model.AppError) {
 		auth.AccessKey = utils.Cfg.FileSettings.AmazonS3AccessKeyId
 		auth.SecretKey = utils.Cfg.FileSettings.AmazonS3SecretAccessKey
 
-		s := s3.New(auth, aws.Regions[utils.Cfg.FileSettings.AmazonS3Region])
+		s := s3.New(auth, awsRegion())
 		bucket := s.Bucket(utils.Cfg.FileSettings.AmazonS3Bucket)
 
 		// try to get the file from S3 with some basic retry logic
@@ -629,3 +629,17 @@ func openFileWriteStream(path string) (io.Writer, *model.AppError) {
 func closeFileWriteStream(file io.Writer) {
 	file.(*os.File).Close()
 }
+
+func awsRegion() aws.Region {
+	if region, ok := aws.Regions[utils.Cfg.FileSettings.AmazonS3Region]; ok {
+		return region
+	}
+
+	return aws.Region{
+		Name:                 utils.Cfg.FileSettings.AmazonS3Region,
+		S3Endpoint:           utils.Cfg.FileSettings.AmazonS3Endpoint,
+		S3BucketEndpoint:     utils.Cfg.FileSettings.AmazonS3BucketEndpoint,
+		S3LocationConstraint: *utils.Cfg.FileSettings.AmazonS3LocationConstraint,
+		S3LowercaseBucket:    *utils.Cfg.FileSettings.AmazonS3LowercaseBucket,
+	}
+}

model/config.go

@@ -68,21 +68,25 @@ type LogSettings struct {
 }
 
 type FileSettings struct {
-	DriverName              string
-	Directory               string
-	EnablePublicLink        bool
-	PublicLinkSalt          string
-	ThumbnailWidth          int
-	ThumbnailHeight         int
-	PreviewWidth            int
-	PreviewHeight           int
-	ProfileWidth            int
-	ProfileHeight           int
-	InitialFont             string
-	AmazonS3AccessKeyId     string
-	AmazonS3SecretAccessKey string
-	AmazonS3Bucket          string
-	AmazonS3Region          string
+	DriverName                 string
+	Directory                  string
+	EnablePublicLink           bool
+	PublicLinkSalt             string
+	ThumbnailWidth             int
+	ThumbnailHeight            int
+	PreviewWidth               int
+	PreviewHeight              int
+	ProfileWidth               int
+	ProfileHeight              int
+	InitialFont                string
+	AmazonS3AccessKeyId        string
+	AmazonS3SecretAccessKey    string
+	AmazonS3Bucket             string
+	AmazonS3Region             string
+	AmazonS3Endpoint           string
+	AmazonS3BucketEndpoint     string
+	AmazonS3LocationConstraint *bool
+	AmazonS3LowercaseBucket    *bool
 }
 
 type EmailSettings struct {
@@ -210,6 +214,16 @@ func (o *Config) SetDefaults() {
 		o.FileSettings.PublicLinkSalt = NewRandomString(32)
 	}
 
+	if o.FileSettings.AmazonS3LocationConstraint == nil {
+		o.FileSettings.AmazonS3LocationConstraint = new(bool)
+		*o.FileSettings.AmazonS3LocationConstraint = false
+	}
+
+	if o.FileSettings.AmazonS3LowercaseBucket == nil {
+		o.FileSettings.AmazonS3LowercaseBucket = new(bool)
+		*o.FileSettings.AmazonS3LowercaseBucket = false
+	}
+
 	if len(o.EmailSettings.InviteSalt) == 0 {
 		o.EmailSettings.InviteSalt = NewRandomString(32)
 	}