Built-in sampling context

You can sample transactions by providing a delegate that makes a decision based on the provided context. Sentry's ASP.NET Core integration automatically exposes useful data as part of that context.

For example, here's how to sample a transaction based on the requested path:

using Sentry;

// Add this to the SDK initialization callback
options.TracesSampler = context =>
{
    var requestPath = context.TryGetHttpPath();

    // We're interested in the checkout page more than others
    if (string.Equals(requestPath, "/checkout", StringComparison.OrdinalIgnoreCase))
    {
        return 0.8; // Sample 80% of checkout transactions
    }

    // Sample only 5% of the everything else
    return 0.05;
};

Besides context.TryGetHttpPath(), you can also use context.TryGetHttpRoute() to get the route name (if available) and context.TryGetHttpMethod() to get the HTTP method used to execute the request.

Note that all these methods may return null. This can happen either if the corresponding property is not available, or if tracing has not been enabled.