Implement an override policy using PostSharp

Question

I would like to do the following:

Suppose I have a logging aspect implemented in a class named LoggingAspect. I would like to configure an entire assembly to log at some log level using the multicast attribute facility. Now suppose I want a specific class in an assembly to have a slightly different log level I would like to decorate the entire class or a specific method in that class and as a result to get a log message with the class specified or method specified level.

My questions are:

1. Is it possible to do it in PostSharp?
2. If it is possible, please specify how?

Thanks

Answer 1

After reading the PostSharp documentation it seems that the solution is to annotate the method with the aspect attribute and then Specify AttributeReplace = true. Here is a complete solution to my question.

Let's suppose I defined a logging aspect in a class named LoggingAspectAttribute that gets a TraceLevel on the constructor. On AssemblyInfo.cs I add the following definition:

[assembly: TracingAspect(TraceLevel.Info,
    AttributeTargetTypes = "PostSharp2.*",
    AttributeTargetTypeAttributes = MulticastAttributes.Public,
    AttributeTargetMemberAttributes = MulticastAttributes.Private | MulticastAttributes.Public)]

PostSharp2 is just the name of the assembly I used to test my solution. This definition causes all my traces to be with the Information TraceLevel.

To override this definition I do the following:

[TracingAspect(TraceLevel.Warning, AttributeReplace = true)]
private static void Bar()
{
    Console.WriteLine("Inside Bar");
}

This causes the trace message for Bar to be with the Warning TraceLevel and all other messages remain with the Information trace level.

Now, if I will omit the AttributeReplace property and leave the attribute annotation as follows:

[TracingAspect(TraceLevel.Warning)]
private static void Bar()
{
    Console.WriteLine("Inside Bar");
}

I will see 2 trace messages from Bar. One with an Information level and another with a warning level.

Hope that helps somebody.