Add SQL query builder base class.

Author: Mohsen Esmailpour

src/Serilog.Ui.Core/QueryBuilder/Sql/SinkColumnNames.cs

@@ -0,0 +1,37 @@
+namespace Serilog.Ui.Core.QueryBuilder.Sql;
+
+/// <summary>
+/// Represents the column names used in the SQL-based sink for logging.
+/// </summary>
+public abstract class SinkColumnNames
+{
+    /// <summary>
+    /// Gets or sets the message of the log entry.
+    /// </summary>
+    public string Message { get; set; } = string.Empty;
+
+    /// <summary>
+    /// Gets or sets the message template of the log entry.
+    /// </summary>
+    public string MessageTemplate { get; set; } = string.Empty;
+
+    /// <summary>
+    /// Gets or sets the level of the log entry.
+    /// </summary>
+    public string Level { get; set; } = string.Empty;
+
+    /// <summary>
+    /// Gets or sets the timestamp of the log entry.
+    /// </summary>
+    public string Timestamp { get; set; } = string.Empty;
+
+    /// <summary>
+    /// Gets or sets the exception of the log entry.
+    /// </summary>
+    public string Exception { get; set; } = string.Empty;
+
+    /// <summary>
+    /// Gets or sets the serialized log event like properties.
+    /// </summary>
+    public string LogEventSerialized { get; set; } = string.Empty;
+}

src/Serilog.Ui.Core/QueryBuilder/Sql/SqlQueryBuilder.cs

@@ -0,0 +1,52 @@
+using Serilog.Ui.Core.Models;
+using static Serilog.Ui.Core.Models.SearchOptions;
+
+namespace Serilog.Ui.Core.QueryBuilder.Sql;
+
+/// <summary>
+/// Abstract class that provides methods to build SQL queries for fetching and counting logs.
+/// </summary>
+public abstract class SqlQueryBuilder
+{
+    /// <summary>
+    /// Builds a SQL query to fetch logs from the specified table.
+    /// </summary>
+    /// <typeparam name="T">The type of the log model.</typeparam>
+    /// <param name="columns">The column names used in the sink for logging.</param>
+    /// <param name="schema">The schema of the table.</param>
+    /// <param name="tableName">The name of the table.</param>
+    /// <param name="query">The query parameters for fetching logs.</param>
+    /// <returns>A SQL query string to fetch logs.</returns>
+    public abstract string BuildFetchLogsQuery<T>(SinkColumnNames columns, string schema, string tableName, FetchLogsQuery query) where T : LogModel;
+
+    /// <summary>
+    /// Builds a SQL query to count logs in the specified table.
+    /// </summary>
+    /// <typeparam name="T">The type of the log model.</typeparam>
+    /// <param name="columns">The column names used in the sink for logging.</param>
+    /// <param name="schema">The schema of the table.</param>
+    /// <param name="tableName">The name of the table.</param>
+    /// <param name="query">The query parameters for counting logs.</param>
+    /// <returns>A SQL query string to count logs.</returns>
+    public abstract string BuildCountLogsQuery<T>(SinkColumnNames columns, string schema, string tableName, FetchLogsQuery query) where T : LogModel;
+
+    /// <summary>
+    /// Generates a SQL sort clause based on the specified sort property and direction.
+    /// </summary>
+    /// <param name="columns">The column names used in the sink for logging.</param>
+    /// <param name="sortOn">The property to sort on.</param>
+    /// <param name="sortBy">The direction to sort by.</param>
+    /// <returns>A SQL sort clause string.</returns>
+    protected static string GenerateSortClause(SinkColumnNames columns, SortProperty sortOn, SortDirection sortBy)
+    {
+        var sortPropertyName = sortOn switch
+        {
+            SortProperty.Timestamp => columns.Timestamp,
+            SortProperty.Level => columns.Level,
+            SortProperty.Message => columns.Message,
+            _ => columns.Timestamp
+        };
+
+        return $"\"{sortPropertyName}\" {sortBy.ToString().ToUpper()}";
+    }
+}

src/Serilog.Ui.Core/Serilog.Ui.Core.csproj

@@ -9,6 +9,6 @@
 	<ItemGroup>
 		<PackageReference Include="Microsoft.Extensions.DependencyInjection.Abstractions" Version="8.0.1" />
 		<PackageReference Include="Microsoft.Extensions.Primitives" Version="8.0.0" />
-		<PackageReference Include="System.Text.Json" Version="8.0.4"/>
+		<PackageReference Include="System.Text.Json" Version="8.0.4" />
 	</ItemGroup>
 </Project>