Add region to gcs gateway example

cmd/gateway-gcs.go

@@ -222,8 +222,28 @@ func (l *gcsGateway) MakeBucket(bucket string) error {
 func (l *gcsGateway) MakeBucketWithLocation(bucket, location string) error {
 	bkt := l.client.Bucket(bucket)
 
+	// this will map s3 regions to google multi regions
+	if v, ok := map[string]string{
+		"ap-northeast-1": "asia",
+		"ap-northeast-2": "asia",
+		"ap-south-1":     "asia",
+		"ap-southeast-1": "asia",
+		"ap-southeast-2": "asia",
+		"eu-central-1":   "eu",
+		"eu-west-1":      "eu",
+		"eu-west-2":      "eu",
+		"ca-central-1":   "us",
+		"sa-east-1":      "us",
+		"us-east-1":      "us",
+		"us-east-2":      "us",
+		"us-west-1":      "us",
+		"us-west-2":      "us",
+	}[location]; ok {
+		location = v
+	}
+
 	if err := bkt.Create(l.ctx, l.projectID, &storage.BucketAttrs{
-		Location: serverConfig.Region,
+		Location: location,
 	}); err != nil {
 		return gcsToObjectError(traceError(err), bucket)
 	}

cmd/gateway-handlers.go

@@ -658,7 +658,10 @@ 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 != location {
+	if serverRegion == "" {
+		// we will only validate the region
+		// when the region has been explicitely set
+	} else if serverRegion != location {
 		writeErrorResponse(w, ErrInvalidRegion, r.URL)
 		return
 	}