Return JSON empty array when not found, and handle null arrays

server/services/store/sqlstore/blocks.go

@@ -218,7 +218,7 @@ func (s *SQLStore) GetAllBlocks() ([]model.Block, error) {
 func blocksFromRows(rows *sql.Rows) ([]model.Block, error) {
 	defer rows.Close()
 
-	var results []model.Block
+	var results = []model.Block{}
 
 	for rows.Next() {
 		var block model.Block

webapp/src/octoClient.ts

@@ -28,7 +28,8 @@ class OctoClient {
     private async getJson(response: Response, defaultValue: any = {}): Promise<any> {
         // The server may return null or malformed json
         try {
-            return await response.json()
+            const value = await response.json()
+            return value || defaultValue
         } catch {
             return defaultValue
         }