RFC: Typed Metric Interfaces

[jaredcnance]

Counters

Expose 3 methods for publishing counters.

metrics.increment('Increment');
metrics.decrement('Decrement');
metrics.count('Count', 10);

{ "Increment": 1, "Decrement": -1, "Count": 10 }

Multiple calls to the same key will be recorded as separate entries. This allows us to preserve the sample count.

metrics.increment('Key');
metrics.increment('Key');
metrics.decrement('Key');

{ "Key": [ 1, 1, -1 ] }

Alternatively, we can use the PMD syntax:

{ 
  "Key": {
      "type": "dist",
      "buckets": "explicit",
      "values": [ 1, -1 ],
      "counts": [ 2, 1 ] 
}

Gauges

metrics.gauge('key', 10);

Timers

metrics.time('key', 10);
timedMetricScope('operation', metrics => {
   // do things and track how long it takes...
})

Histograms: TBD

metrics.histo('key', 10);

{ 
  "Key": {
    "type": "dist",
    "buckets": "explicit",
    "values": [ 1 ],
    "counts": [ 10 ]
  } 
}