ILogger structured loggig with Application Insights not working in .Net 5 Azure Function

Question

ILogger structured loggig with Application Insights not working in .Net 5 Azure Function

Dietmar 111

Following the guide of creating the HttpExample for .Net 5 based Azure Functions, I'm failing setting up structured logging.

My relevant code is:

[Function("HttpExample")]  
public static HttpResponseData Run([HttpTrigger(AuthorizationLevel.Anonymous, "get", "post")] HttpRequestData req, FunctionContext executionContext)  
{  
    var logger = executionContext.GetLogger("HttpExample");  
    logger.LogInformation("Example {ExampleValue}", 1001);

I would expect to get a logging record in Application Insights with a customDimensions property prop__ExampleValue, with a value of 1001.

This is however not the case. No matter what I try, I get the log entry as simple string, but not split into custom name/value pairs.

Any help would be highly appreciated.

Thanks in advance,
Dietmar

Nasreen Akter 10,811 Reputation points Volunteer Moderator

2021-04-27T12:10:18.637+00:00

Hi @Dietmar ,

Please check the following link, it might be helpful. Thanks!

https://camerondwyer.com/2020/05/26/how-to-use-application-insights-custom-properties-in-azure-monitor-log-kusto-queries/

Dietmar 111

Hi @Nasreen Akter ,

many thanks for your reply.

I already tried this and this is working neither.

For me there is no way getting custom properties into the Applications Insights log. Should be easily reproducible with the vanilla HTTPExample. 3 simple tests which are all failing:

logger.LogInformation("Example {ExampleValue}", 1001); //Logs only as a string, prop__ExampleValue missing  

using (_logger.BeginScope("ScopeTest"))  
{  
    _logger.LogInformation("Scope logging test"); //Logs only the string, scope missing  
}  

Dictionary<string, string> certifcateProperties = new Dictionary<string, string>()  
{  
    { "Prop1", "abc" },  
    { "Prop2", "def" },  
};  
 _logger.LogInformation("CustomProperties", certifcateProperties); //Logs only the string, dictionary content missing completely

Looks like a bug?

Thanks,
Dietmar

1 answer

Your answer

Nasreen Akter 10,811 Reputation points Volunteer Moderator

2021-04-27T12:10:18.637+00:00

Hi @Dietmar ,

Please check the following link, it might be helpful. Thanks!

https://camerondwyer.com/2020/05/26/how-to-use-application-insights-custom-properties-in-azure-monitor-log-kusto-queries/
Dietmar 111 Reputation points

2021-04-27T12:55:01.743+00:00

Hi @Nasreen Akter ,

many thanks for your reply.

I already tried this and this is working neither.

For me there is no way getting custom properties into the Applications Insights log. Should be easily reproducible with the vanilla HTTPExample. 3 simple tests which are all failing:

logger.LogInformation("Example {ExampleValue}", 1001); //Logs only as a string, prop__ExampleValue missing using (_logger.BeginScope("ScopeTest")) { _logger.LogInformation("Scope logging test"); //Logs only the string, scope missing } Dictionary<string, string> certifcateProperties = new Dictionary<string, string>() { { "Prop1", "abc" }, { "Prop2", "def" }, }; _logger.LogInformation("CustomProperties", certifcateProperties); //Logs only the string, dictionary content missing completely

Looks like a bug?

Thanks,
Dietmar

Answer 1

Hi @Dietmar

I think I am seeing the same issue as you.

I am porting some simple in-process functions from a dotnet 3.1 function app to a new isolated .net 5 function app.

I am making simple log statements such as the one you have detailed above but when I check in app insights the structured logging capabilities are not working.

Looks like it is an active issue being tracked here:

https://github.com/Azure/azure-functions-host/issues/7452

The fix is tentatively scheduled for today based on sprint 108:

https://github.com/Azure/azure-functions-host/milestone/141

Maybe we'll get an update later today.

Share via

ILogger structured loggig with Application Insights not working in .Net 5 Azure Function

1 answer

Your answer