Opinionated performance metric tracking for Koa, implemented with DogStatsD.

yarn add @shopify/koa-metrics

import Koa from 'koa';
import metrics from '@shopify/koa-metrics';

const app = new Koa();

app.use(
  metrics({
    prefix: 'AppName',
    host: 'some-statsd-host.com:8125',
  }),
);

The passed in options object adheres to the following API:

The global StatsD metric name prefix; should be provided in PascalCase.

The url for the StatsD host; should be provided in the format: hostname:port.

An instance of the Metrics object will be available on ctx.metrics further down in the middleware stack.

Sends a distribution command with the specified value in milliseconds.

Returns a new Timer started at the current process.hrtime()

Returns the time, in milliseconds, since the Timer was created.

tags are an object keyed by the name of the corresponding tag. For example:

{
  name: value,
  name2: value2
}

The global metric name prefix is provided through the options object.

This package automatically provides performance metrics for HTTP requests.

• path
• request_method
• response_code
• response_type (eg. 2xx, 3xx, ...)

Time to complete a request, from the application perspective.

Time before a request actually started being processed.

This metric is emitted when the application start processing a request. It relies on the presence of a header X-Request-Start set by the first HTTP hop.

This metric is based on the response header Content-Length. Some responses don't provide this header (chunked encoding); in those cases, this will not be reported.