assignMetrics

const assignMetrics: (config?) => Policy

Defined in: src/policies/observability/assign-metrics.ts:43

Attach metric tags to the request context for downstream consumers.

Tags are resolved (static or dynamic) and stored as a plain object at c.get("_metricsTags"). The metricsReporter policy (or any custom observer) can read these tags to enrich collected metrics.

Parameters

config?

AssignMetricsConfig

Must include tags — a record of tag names to values or resolver functions.

Returns

Policy

A Policy at priority 0 (OBSERVABILITY).

Example

import { assignMetrics } from "@homegrower-club/stoma";

assignMetrics({
  tags: {
    service: "users-api",
    region: (c) => c.req.header("cf-ipcountry") ?? "unknown",
  },
});