Eik server - Metrics

The Eik server exposes a metric stream which emits internal metrics on the server. These metrics are intended to give numbers on how the server as an application is behaving and performing and is an important tool in the toolbox for monitoring the servers health status. These metrics do not provide statistics on assets uploaded to the asset server.

The metrics the server provides are not bound to any particular metric system so it's possible to provide the metrics to any monitoring system as preferred. The metric stream emits a set of generic metric objects that can be altered and piped as desired.

Please see @metrics/client for examples of how to consume these metrics in your preferred monitoring system.

Usage

The @eik/service module exposes a .metric property. This property holds a plain Node.js object stream which emits the metrics as objects on the stream.

This stream can be piped into a metrics consumer or any other Node.js writable / transform stream for further processing.

Example of metrics being piped into a prometheus consumer:

const MetricsConsumer = require('@metrics/prometheus-consumer');
const prometheus = require('prom-client');
const Service = require('@eik/service');
const fastify = require('fastify');

const service = new Service();

const metricsConsumer = new MetricsConsumer({
    client: prometheus,
});

service.metrics.pipe(metricsConsumer);

const app = fastify();
app.register(service.api());

app.get('/_/metrics', (request, reply) => {
    reply.type(metricsConsumer.registry.contentType);
    reply.send(metricsConsumer.registry.metrics());
});

const run = async () => {
    await app.listen(8080, '0.0.0.0');
}
run();

Metrics

Each metric provided by the server has a unique name and a type defining what type (counter, histogram, etc) of metric it is.

The server exposes these metrics:

Name	Type	Description
eik_core_auth_post_handler	histogram	Time taken in a login method
eik_core_pkg_get_handler	histogram	Time taken in a public package method
eik_core_pkg_log_handler	histogram	Time taken in a package version overview method
eik_core_pkg_put_handler	histogram	Time taken in a upload package method
eik_core_versions_get_handler	histogram	Time taken in a latest package versions method
eik_core_alias_get_handler	histogram	Time taken in a public alias method
eik_core_alias_put_handler	histogram	Time taken in a create alias method
eik_core_alias_post_handler	histogram	Time taken in a update alias method
eik_core_alias_del_handler	histogram	Time taken in a delete alias method
eik_core_map_get_handler	histogram	Time taken in a public import maps method
eik_core_map_put_handler	histogram	Time taken in a upload import maps method