我使用Serilog成功创建了一个记录器,但是在创建记录器之前,我无法确定如何确定要记录的SQL Server数据库是否存在。目标是在我的Main函数的这一行之前创建记录器,以便获得所有启动日志:
var host = CreateHostBuilder(args).Build();
但是,如果我这样做了,并且数据库还不存在,那么在我第一次启动应用程序时就不会创建日志表。它将在我第二次启动应用程序时创建,因为在该行代码之后我正在创建数据库并为其添加种子。
如果数据库存在,我想在CreateHostBuilder运行之前创建记录器,或者如果数据库还不存在,则在CreateHostBuilder和SeedDatabase运行之后创建记录器。我也不能两次运行CreateLogger(),否则会得到异常。
这里是代码:
public static void Main(string[] args)
{
try
{
// If I create the logger here I'll see all the startup logs
// if the database exists. If the database doesn't exist yet the
// logging table won't get created until the second time I startup the app.
CreateLogger();
Log.Information("Starting Up");
var host = CreateHostBuilder(args).Build();
SeedDatabase(host);
// If I create the logger here I don't get all of the startup logs but
// it ensures that if the database hasn't been created and seeded yet the
// logging table is still created.
CreateLogger();
host.Run();
}
catch (Exception exception)
{
Log.Fatal(exception, "Application start-up failed");
}
finally
{
Log.CloseAndFlush();
}
}
public static void CreateLogger()
{
Log.Logger = new LoggerConfiguration()
// Add/Update configuration settings in appsettings.json.
// Don't add them here.
.ReadFrom.Configuration(Configuration)
.Enrich.FromLogContext()
.CreateLogger();
}
<< [UPDATED appsettings.json添加文件记录后:
"Serilog": {
"MinimumLevel": "Information",
"WriteTo": [
{
"Name": "MSSqlServer",
"Args": {
"connectionString": "DbContext",
"tableName": "EventLog",
"autoCreateSqlTable": true
}
}
],
"WriteTo:Async": {
"Name": "Async",
"Args": {
"configure": [
{
"Name": "File",
"Args": {
"path": "../../EventLogs/",
"rollingInterval": "Day"
}
}
]
}
}
}