Csharp 分别切换用于读取和写入的EF核心日志(log)

发布于11月13日

要切换EF核心SQL日志(log)记录，可以在appsettings.json中使用以下命令:

"Logging": {
  "LogLevel": {
    //...
    "Microsoft.EntityFrameworkCore.Database.Command": "Information" //or "Warning"
  }
}

在开发过程中，EF Core默认在"信息"级别记录查询;因此可以使用"警告"使其静音.

But that applies to both reads and writes.当我遇到EF问题时，几乎总是与写入有关-所以我启用了日志(log)记录，并获得了大量的读取日志(log)，这使得调试变得困难.

是否可以分别切换读取和写入的日志(log)记录？

推荐答案

是否可以分别切换读取和写入的日志(log)记录？

Use this in only Development Environment个

我会这样做:

使用DbCommandInterceptor类拦截执行的SQL语句. 因此，首先我创建一个继承DbCommandInterceptor的类QueryCommandInterceptor :

public class QueryCommandInterceptor : DbCommandInterceptor
{
 private readonly ILogger<QueryCommandInterceptor> _logger;

 public QueryCommandInterceptor(ILogger<QueryCommandInterceptor> logger)
 {
     _logger = logger;
 }
}

添加该方法以判断该命令是否为写操作，即DELETE、UPDATE、INSERT，如果是，还记录该命令:

private void LogCommand(DbCommand command)
{
    if (command.CommandText.Contains("INSERT") ||
           command.CommandText.Contains("UPDATE") ||
           command.CommandText.Contains("DELETE"))
    {
        _logger.LogInformation($"Executing SQL command: {command.CommandText}");
    }
}

DbCommandInterceptor中的最后QueryCommandInterceptor个重写方法:

using Microsoft.EntityFrameworkCore.Diagnostics;
using System.Data.Common;

namespace StackOverflow
{
    public class QueryCommandInterceptor : DbCommandInterceptor
    {
        private readonly ILogger<QueryCommandInterceptor> _logger;

        public QueryCommandInterceptor(ILogger<QueryCommandInterceptor> logger)
        {
            _logger = logger;
        }
        public override InterceptionResult<int> NonQueryExecuting(
           DbCommand command,
           CommandEventData eventData,
           InterceptionResult<int> result)
        {
            LogCommand(command);
            return result;
        }

        public override ValueTask<InterceptionResult<int>> NonQueryExecutingAsync(
            DbCommand command,
            CommandEventData eventData,
            InterceptionResult<int> result,
            CancellationToken cancellationToken = default)
        {
            LogCommand(command);
            return new ValueTask<InterceptionResult<int>>(result);
        }

        public override InterceptionResult<DbDataReader> ReaderExecuting(
            DbCommand command,
            CommandEventData eventData,
            InterceptionResult<DbDataReader> result)
        {
            LogCommand(command);
            return result;
        }

        public override ValueTask<InterceptionResult<DbDataReader>> ReaderExecutingAsync(
            DbCommand command,
            CommandEventData eventData,
            InterceptionResult<DbDataReader> result,
            CancellationToken cancellationToken = default)
        {
            LogCommand(command);
            return new ValueTask<InterceptionResult<DbDataReader>>(result);
        }

        public override InterceptionResult<object> ScalarExecuting(
           DbCommand command,
           CommandEventData eventData,
           InterceptionResult<object> result)
        {
            LogCommand(command);
            return result;
        }

        public override ValueTask<InterceptionResult<object>> ScalarExecutingAsync(
            DbCommand command,
            CommandEventData eventData,
            InterceptionResult<object> result,
            CancellationToken cancellationToken = default)
        {
            LogCommand(command);
            return new ValueTask<InterceptionResult<object>>(result);
        }
        private void LogCommand(DbCommand command)
        {
            if (command.CommandText.Contains("INSERT") ||
                   command.CommandText.Contains("UPDATE") ||
                   command.CommandText.Contains("DELETE"))
            {
                _logger.LogInformation($"Executing SQL command: {command.CommandText}");
            }
        }
       
    }
}

最后，在我的Program.cs中连接我的记录器，也添加了新的拦截器:

builder.Logging.ClearProviders();
var logger = LoggerFactory.Create(builder =>
{
    builder.AddConsole();
}).CreateLogger<QueryCommandInterceptor>();

builder.Services.AddDbContext<StackContext>(options => 
{
    options.UseSqlServer(connectionString);
    options.AddInterceptors(new QueryCommandInterceptor(logger)); 
}
);