Cleanup and update the PR with the master branch.

cmd/gateway-azure.go

@@ -166,7 +166,7 @@ func newAzureLayer(args cli.Args) (GatewayLayer, error) {
 	secure := true
 
 	// If user provided some parameters
-	if len(args) > 0 {
+	if args.Present() {
 		endPoint, secure, err = parseGatewayEndpoint(args.First())
 		if err != nil {
 			return nil, err

cmd/gateway-gcs-anonymous.go

@@ -94,7 +94,7 @@ func (l *gcsGateway) AnonGetObjectInfo(bucket string, object string) (objInfo Ob
 		objInfo.UserDefined["Content-Encoding"] = resp.Header.Get("Content-Encoding")
 	}
 	objInfo.UserDefined["Content-Type"] = resp.Header.Get("Content-Type")
-	objInfo.MD5Sum = resp.Header.Get("Etag")
+	objInfo.ETag = resp.Header.Get("Etag")
 	objInfo.ModTime = t
 	objInfo.Name = object
 	objInfo.Size = contentLength

cmd/gateway-gcs.go

@@ -351,7 +351,7 @@ func (l *gcsGateway) ListObjects(bucket string, prefix string, marker string, de
 			Bucket:          attrs.Bucket,
 			ModTime:         attrs.Updated,
 			Size:            attrs.Size,
-			MD5Sum:          hex.EncodeToString(attrs.MD5),
+			ETag:            hex.EncodeToString(attrs.MD5),
 			UserDefined:     attrs.Metadata,
 			ContentType:     attrs.ContentType,
 			ContentEncoding: attrs.ContentEncoding,
@@ -443,7 +443,7 @@ func fromGCSObjectInfo(attrs *storage.ObjectAttrs) ObjectInfo {
 		Bucket:          attrs.Bucket,
 		ModTime:         attrs.Updated,
 		Size:            attrs.Size,
-		MD5Sum:          hex.EncodeToString(attrs.MD5),
+		ETag:            hex.EncodeToString(attrs.MD5),
 		UserDefined:     attrs.Metadata,
 		ContentType:     attrs.ContentType,
 		ContentEncoding: attrs.ContentEncoding,
@@ -691,7 +691,7 @@ func (l *gcsGateway) PutObjectPart(bucket string, key string, uploadID string, p
 	return PartInfo{
 		PartNumber:   partID,
 		LastModified: info.ModTime,
-		ETag:         info.MD5Sum,
+		ETag:         info.ETag,
 		Size:         info.Size,
 	}, err
 }

cmd/gateway-handlers.go

@@ -657,10 +657,7 @@ func (api gatewayAPIHandlers) PutBucketHandler(w http.ResponseWriter, r *http.Re
 	// reads body which has been read already. So only validating
 	// region here.
 	serverRegion := serverConfig.GetRegion()
-	if serverRegion == "" {
+	if serverRegion != "" && serverRegion != location {
-		// we will only validate the region
-		// when the region has been explicitely set
-	} else if serverRegion != location {
 		writeErrorResponse(w, ErrInvalidRegion, r.URL)
 		return
 	}

cmd/gateway-main.go

@@ -178,17 +178,6 @@ const (
 	// Add more backends here.
 )
 
-// GatewayFn returns the GatewayLayer for the backend
-type GatewayFn func(cli.Args) (GatewayLayer, error)
-
-var (
-	backends = map[gatewayBackend]GatewayFn{
-		azureBackend: newAzureLayer,
-		s3Backend:    newS3Gateway,
-		gcsBackend:   newGCSGateway,
-	}
-)
-
 // Returns access and secretkey set from environment variables.
 func mustGetGatewayConfigFromEnv() (string, string, string) {
 	// Fetch access keys from environment variables.
@@ -225,18 +214,17 @@ func mustSetBrowserSettingFromEnv() {
 // Supported backend types are
 //
 // - Azure Blob Storage.
-// - S3 Object Storage.
+// - AWS S3.
 // - Google Cloud Storage.
 // - Add your favorite backend here.
-func newGatewayLayer(backendType gatewayBackend, endpoint, accessKey, secretKey string, secure bool) (GatewayLayer, error) {
+func newGatewayLayer(backendType string, args cli.Args) (GatewayLayer, error) {
-
 	switch gatewayBackend(backendType) {
 	case azureBackend:
-		return newAzureLayer(endpoint, accessKey, secretKey, secure)
+		return newAzureLayer(args)
 	case s3Backend:
-		return newS3Gateway(endpoint, accessKey, secretKey, secure)
+		return newS3Gateway(args)
 	case gcsBackend:
-		return newGCSGateway(endpoint, accessKey, secretKey, secure)
+		return newGCSGateway(args)
 	}
 
 	return nil, fmt.Errorf("Unrecognized backend type %s", backendType)
@@ -371,15 +359,10 @@ func gatewayMain(ctx *cli.Context, backendType gatewayBackend) {
 	err := validateGatewayArguments(serverAddr, endpointAddr)
 	fatalIf(err, "Invalid argument")
 
-	// Second argument is endpoint.	If no endpoint is specified then the
-	// gateway implementation should use a default setting.
-	endPoint, secure, err := parseGatewayEndpoint(endpointAddr)
-	fatalIf(err, "Unable to parse endpoint")
-
 	// Create certs path for SSL configuration.
 	fatalIf(createConfigDir(), "Unable to create configuration directory")
 
-	newObject, err := newGatewayLayer(backendType, endPoint, accessKey, secretKey, secure)
+	newObject, err := newGatewayLayer(backendType, ctx.Args()[1:])
 	fatalIf(err, "Unable to initialize gateway layer")
 
 	initNSLock(false) // Enable local namespace lock.

cmd/gateway-s3.go

@@ -110,7 +110,7 @@ func newS3Gateway(args cli.Args) (GatewayLayer, error) {
 	secure := true
 
 	// Check if user provided some parameters
-	if len(args) > 0 {
+	if args.Present() {
 		// Override default params if the endpoint is provided
 		endpoint, secure, err = parseGatewayEndpoint(args.First())
 		if err != nil {