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We use this within our components to publish statsd metrics from .NET code. We've been using this in most of our things, since around 2013.

• statsd metrics formatter
• UDP client handling

IStatsDPublisher is the interface that you will use in most circumstances. With this you can Increment or Decrement an event, and send values for a Gauge or Timing.

The concrete class that implements IStatsDPublisher is StatsDPublisher. The constructor takes an instance of StatsDConfiguration. For the configuration's values, you will always need the statsd server host name or IP address. Optionally, you can change the standard port (8125). You can also prepend a prefix to all stats. These values often come from configuration as the host name and/or prefix may vary between test and production environments.

An example of a very simple statsd publisher configuration, using the default values for most things.

var statsDConfig = new StatsDConfiguration { Host = "metrics_server.mycompany.com" };
IStatsDPublisher statsDPublisher = new StatsDPublisher(statsDConfig);

An example of IoC in NInject for statsd publisher with values for all options, read from configuration:

// read config values from app settings
string statsdHostName =  ConfigurationManager.AppSettings["statsd.hostname"];
int statsdPort = int.Parse(ConfigurationManager.AppSettings["statsd.port"]);
string statsdPrefix =  ConfigurationManager.AppSettings["statsd.prefix"];

// assemble a StatsDConfiguration object
// since the configuration doesn't change for the lifetime of the app, 
// it can be a preconfigured singleton instance
var statsDConfig = new StatsDConfiguration
{
  Host = statsdHostName,
  Port = statsdPort,
  Prefix = statsdPrefix,
  Culture = CultureInfo.InvariantCulture
};

// register with NInject
Bind<StatsDConfiguration>().ToConstant(statsDConfig>);
Bind<IStatsDPublisher>().To<StatsDPublisher>();

Given an existing instance of IStatsDPublisher called stats you can do for e.g.:

stats.Increment("DoSomething.Attempt");
var stopWatch = Stopwatch.StartNew();
var success = DoSomething();

stopWatch.Stop();

var statName = "DoSomething." + success ? "Success" : "Failure";
stats.Timing(statName, stopWatch.Elapsed);

This syntax for timers less typing in simple cases, where you always want to time the operation, and always with the same stat name. Given an existing instance of IStatsDPublisher you can do:

//  timing a block of code in a using statement:
using (stats.StartTimer("someStat"))
{
    DoSomething();
}

// also works with async
using (stats.StartTimer("someStat"))
{
    await DoSomethingAsync();
}

The StartTimer returns an IDisposableTimer that wraps a stopwatch and implements IDisposable. The stopwatch is automatically stopped and the metric sent when it falls out of scope and is disposed on the closing } of the using statement.

Sometimes the decision of which stat to send should not be taken before the operation completes. e.g. When you are timing http operations and want different status codes to be logged under different stats.

The IDisposableTimer has a StatName property to set or change the name of the stat. To use this you need a reference to the timer, e.g. using (var timer = stats.StartTimer("statName")) instead of using (stats.StartTimer("statName"))

The stat name must be set to a non-empty string at the end of the using block.

using (var timer = stats.StartTimer("SomeHttpOperation."))
{
    var response = DoSomeHttpOperation();
    timer.StatName = timer.StatName + (int)response.StatusCode;
    return response;
}

//  timing an action without a return value:
stats.Time("someStat", t => DoSomething());

//  timing a function with a return value:
var result = stats.Time("someStat", t => GetSomething());

// and it correctly times async code using the usual syntax:
await stats.Time("someStat", async t => await DoSomethingAsync());
var result = await stats.Time("someStat", async t => await GetSomethingAsync());

In all these cases the function or delegate is supplied with a IDisposableTimer t so that the stat name can be changed if need be.

The idea of "disposable timers" for using statements is an old one, see for example this StatsD client.

See CONTRIBUTING.md.

See CONTRIBUTING.md.