Where in Azure Portal are the logger.Log statements? - azure

Question

I have a .NET Core WebAPI app. The app is deployed on Azure as an App Service.
In the code, I have enabled Application Insights like so
public static IWebHost BuildWebHost(string[] args) =>
WebHost
.CreateDefaultBuilder(args)
.UseApplicationInsights()
.UseStartup<Startup>()
.ConfigureLogging((hostingContext, logging) =>
{
logging.AddConfiguration(hostingContext.Configuration.GetSection("Logging")).SetMinimumLevel(Microsoft.Extensions.Logging.LogLevel.Error);
logging.AddApplicationInsights(" xxxxx-xxxx-xxxx-xxxx--xxxxxxxxxxx").SetMinimumLevel(LogLevel.Trace);
})
.Build();
In the constructor of a controller and inside an method of a controller I have these logging statements.
_logger.LogInformation("ApiController, information");
_logger.LogWarning("ApiController, warning");
_logger.LogCritical("ApiController, critical");
_logger.LogWarning("ApiController, error");
_logger.LogDebug("ApiController, debug");
In the Azure Portal I have Application Insights for my App Service enabled. Here a picture from the portal.
App Insights in Azure Portal
But where do I see the logging statements in the Azure portal?
When I go to Application Insights -> Logs and I query by
search *
I can see the requests made to the API but not the logging statements.
Application Insights Log
Where are the log statements?

Answer 1

First, it is not good practice to configure the log level in code. You can easily configure the log level in the appsettings.json file. So in Program.cs -> public static IWebHost BuildWebHost method, change the code to below:
public static IWebHost BuildWebHost(string[] args) =>
WebHost.CreateDefaultBuilder(args)
.UseApplicationInsights()
.UseStartup<Startup>()
.Build();
Then in appsettings.json(also right click the file -> properties -> set "copy to output directory" to "Copy if newer"):
{
"Logging": {
"IncludeScopes": false,
"ApplicationInsights": {
"LogLevel": {
"Default": "Trace"
}
},
"Console": {
"LogLevel": {
"Default": "Warning"
}
}
},
"ApplicationInsights": {
"InstrumentationKey": "the key"
}
}
In Controller, like ValuesController:
public class ValuesController : Controller
{
private readonly ILogger _logger;
public ValuesController(ILoggerFactory loggerFactory)
{
_logger = loggerFactory.CreateLogger<ValuesController>();
}
// GET api/values
[HttpGet]
public IEnumerable<string> Get()
{
_logger.LogInformation("ApiController, information");
_logger.LogWarning("ApiController, warning");
_logger.LogCritical("ApiController, critical");
_logger.LogWarning("ApiController, error");
_logger.LogDebug("ApiController, debug");
return new string[] { "value1", "value2" };
}
}
Run the project, and wait for a few minutes(application insights would always take 3 to 5 minutes or more to display the data). Then nave to azure portal -> application insights logs, remember that all the logs written by ILogger are stored in "traces" table. Just write the query like "traces" and specify a proper time range, you should see all the logs like below: