Register or fetch a counter. Counters are monotonic (only inc).
Register or fetch a gauge. Gauges can move in any direction.
Drop every label series. For a gauge whose label set is derived
from a peer-chosen identifier (e.g. a room id) and refreshed by
re-setting each live member on every scrape, a series for a
member that has since disappeared (a room that unloaded) is
never overwritten and would otherwise report its last known
value forever. Call this before the refresh loop so the render
reflects only currently-live members.
Tiny histogram: tracks sum and count. Apps can compute average
client-side. Real bucketed histograms are also available via
bucketedHistogram(name, buckets, help).
Render the full registry as Prometheus text format.
Prometheus-style bucketed histogram.
bucketsare upper bounds (e.g.[5, 10, 25, 50, 100, 250, 500, 1000, 2500, 5000]). Each observation increments every bucket whose upper bound it doesn't exceed, plussumandcount. Render output uses the conventional<name>_bucket{le="<bound>"}labels.