Htykuut

As per the Azure documentation, Functions V2 uses the .NET Core logging filter hierarchy for configuration.

In the following example, an instance of ILogger is injected into the Run method of the function.

[FunctionName("MyFunction")]

public static void Run([TimerTrigger("0 */1 * * * *")]TimerInfo myTimer, ILogger logger, ExecutionContext executionContext)

{

    logger.LogInformation("I don't want to see this in production!"));

}

When inspecting the ILogger object, each LoggerInformation element has MinLevel of null which seems to log all levels.

In production, I only want to log at the Error level. I would like to be able to configure this using an environment variable but I cannot find any documentation which explains how to achieve this. I have tried adding the following environment variable to no effect:

"logging__logLevel__Default: "Error" 

I am afraid we can't configure the log level using environment variables. When function host starts, it reads log level from host.json and inject ILogger instance with corresponding filter rules. Host configurations are not env variables, but we can modify host.json to change log level.

v2 log configuration in host.json.

"logging": {

    "logLevel": {

     // For specific function

     "Function.MyFunction1": "Information",

     // For all functions

     "Function":"Error",

     // Default settings, e.g. for host 

     "default": "None"

    }

}