C# ASP.NET Core DI with logging

Question

I'm looking for DI solution for the following problem. I'm writing a custom SeriLog sync that requires a dependency from my serviceprovider. I can't seem to figure out how to access my serviceprovider from services.AddLogging():

services.AddSingleton<ICosmosFactory, CosmosFactory>();
services.AddLogging((builder) =>
{
    var logger = new LoggerConfiguration()
        .MinimumLevel.Verbose()
        .WriteTo.AzureCosmosDB(
            client: sp.Client,
            databaseName: "MyDb",
            collectionName: "logging",
            timeToLive: TimeSpan.FromDays(7)
           )
        .CreateLogger();
            builder.AddSerilog(logger);
});

In this example, Serilogs Sync needs an instance of CosmosClient which is provided by CosmosFactory. The only way I can see to grab it is to do the following:

builder.Services.BuildServiceProvider()

This is not ideal as it could potentially create duplicates of my singleton services.

Answer 1

I have no idea if this is the best approach. But playing around with it. I found the best way is to inject a ILoggerFactory as a singleton and configure that instead.

services.AddSingleton<ILoggerFactory>(sp =>
{
    var factory = new LoggerFactory();
    var logger = new LoggerConfiguration();
    Serilog.Events.LogEventLevel level = Serilog.Events.LogEventLevel.Debug;
    logger.WriteTo.AzureCosmosDB(
        client:((ICosmosFactory)sp.GetRequiredService(typeof(ICosmosFactory))).Client,
        databaseName: "Diagnostics",
        collectionName: "logging",
        timeToLive: TimeSpan.FromDays(logTTL),
        restrictedToMinimumLevel: level
        );
    return factory;
});

If someone has a better answer or a reason this isnt a good answer. Please let me know.