In a standard request/response app with AspNet.Core, it was easy to add informations to the request context so that every single log entry could have access to them automatically. For exemple, if I need that all my log entries have the logged UserName and the FormId that he is presently editing, I just had to create a new Middleware that use ILogger.BeginScope to achieve that and register the middleware at the beginning of the pipeline.
public class FormLogEnricherMiddleware : IMiddleware{ private readonly IMyForm _myForm; private readonly ILogger<FormLogEnricherMiddleware > _logger; public FormLogEnricherMiddleware(IMyForm myForm, ILogger<FormLogEnricherMiddleware> logger) { _myForm = myForm; _logger = logger; } public Task InvokeAsync(HttpContext context, RequestDelegate next) { var scopeTags = new Dictionary<string, object>() { ["UserName"] = context.User?.Identity?.Name, ["FormId"] = _myForm.FormId }; using (_logger.BeginScope(scopeTags)) { return next(context); } }}Program.cs
...builder.Services.AddControllersWithViews();builder.Services.AddScoped<FormLogEnricherMiddleware>();var app = builder.Build();app.UseMiddleware<FormLogEnricherMiddleware>();// Configure the HTTP request pipeline.if (!app.Environment.IsDevelopment()){ app.UseExceptionHandler("/Home/Error"); // The default HSTS value is 30 days. You may want to change this for production scenarios, see https://aka.ms/aspnetcore-hsts. app.UseHsts();}app.UseHttpsRedirection();app.UseStaticFiles();...HomeController.cs
_logger.LogInformation("This is a test");Result
Now that we use Blazor Server with web sockets, the middleware way is not working anymore. So how can we add informations in a ILogger scope so that every log have access to them automatically?