#4303: add search function.

Oqtane.Shared/Interfaces/ISearchProvider.cs

@@ -0,0 +1,26 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using Oqtane.Models;
+
+namespace Oqtane.Services
+{
+    public interface ISearchProvider
+    {
+        string Name { get; }
+
+        void SaveDocument(SearchDocument document, bool autoCommit = false);
+
+        void DeleteDocument(string id);
+
+        Task<SearchResults> SearchAsync(SearchQuery searchQuery, Func<SearchDocument, SearchQuery, bool> validateFunc);
+        
+        bool Optimize();
+
+        void Commit();
+
+        void ResetIndex();
+    }
+}