PrometheusMetricName.ts

import { ValidatedString, type ValidatedStringFactory } from './ValidatedString.ts';

const isPrometheusMetricName = (s: string): boolean => /^[a-zA-Z_:][a-zA-Z0-9_:]*$/.test(s);

/**
 Why JSRCompatibleFactory? See https://github.com/axhxrx/validated-string/issues/1 — consumers of this lib probably don't need to deal with this
 */
const JSRCompatibleFactory = ValidatedString.create(isPrometheusMetricName, {
  name: 'PrometheusMetricName',
  description: 'must start with a letter, underscore, or colon, followed by letters, digits, underscores, or colons',
});

const type: ValidatedString<typeof isPrometheusMetricName> = JSRCompatibleFactory.type;
const factory: ValidatedStringFactory<typeof isPrometheusMetricName> = JSRCompatibleFactory.factory;

/**
 A validated string that represents a Prometheus metric name. See {@link ValidatedString} for more information. Note that this might not really exactly match the rules for Prometheus metric names, but it's close enough for our purposes; namely, generating metrics — don't rely on this to *validate* Prometheus metric names, as it is based on a quick skim of the Prometheus docs.

 @category Prometheus
 */
export type PrometheusMetricName = typeof type;
export const PrometheusMetricName = factory;