Open anuptalwalkar opened 7 years ago
We've not implemented Null
, Statsd
or Prometheus
yet for the cached stats reporter.
For testing purposes I will need to use use Statsd
and Null
reporters soon, I can contribute these to tally.
I've currently worked around it on master by having all tests use an InternalMetricsReporter
.
I don't personally use Prometheus so someone else will need to have look into implementing CachedRepoter for Prometheus.
I have a NopCachedStatsReporter written for testing - https://github.com/uber-go/fx/blob/master/metrics/nop_reporter.go I am happy to share if needed.
@anuptalwalkar is there any reason you can't use a tally.TestScope
?
You can create one by calling tally.NewTestScope(...)
as implemented here:
func NewTestScope(
prefix string,
tags map[string]string,
) TestScope {
// ...
}
Then you get the following abilities:
type TestScope interface {
Scope
// Snapshot returns a copy of all values since the last report execution,
// this is an expensive operation and should only be use for testing purposes
Snapshot() Snapshot
}
// Snapshot is a snapshot of values since last report execution
type Snapshot interface {
// Counters returns a snapshot of all counter summations since last report execution
Counters() map[string]CounterSnapshot
// Gauges returns a snapshot of gauge last values since last report execution
Gauges() map[string]GaugeSnapshot
// Timers returns a snapshot of timer values since last report execution
Timers() map[string]TimerSnapshot
}
// CounterSnapshot is a snapshot of a counter
type CounterSnapshot interface {
// Name returns the name
Name() string
// Tags returns the tags
Tags() map[string]string
// Value returns the value
Value() int64
}
// GaugeSnapshot is a snapshot of a gauge
type GaugeSnapshot interface {
// Name returns the name
Name() string
// Tags returns the tags
Tags() map[string]string
// Value returns the value
Value() float64
}
// TimerSnapshot is a snapshot of a timer
type TimerSnapshot interface {
// Name returns the name
Name() string
// Tags returns the tags
Tags() map[string]string
// Values returns the values
Values() []time.Duration
}
The issue here is doing a setup function to return the scope, reporter and closer can not easily be replaced today. The NullStatsReporter
does not implement CachedStatsReporter
interface.
The use case is something I want to test with as well. If you make a public function to create the metrics with a CachedStatsReporter
and need to test it out there is no supporting tally NullCachedStatsReporter
.
Example from my use case as well. https://github.com/jeffbean/zkpacket/blob/master/metrics.go
@robskillington, @jeffbean answered your question. The M3 backend also takes CachedStatsReporter
instead of StatsReported
. This prompted me to have NopCachedStatsReporter
for nop use cases. Updated implementation is here with histogram support - https://github.com/uber-go/fx/pull/334 This should be part of Tally.
Hey, cool no problems. Sure if you don't want to collect the actual values then a nil
reporter is useful. Let me add.
any update on this? @robskillington
Not sure about @jeffbean, but FX doesn't need this any more. Unless Bean still needs this functionality, feel free to close this.
I see that we have implemented
CachedStatsReporter
here, https://github.com/uber-go/tally/pull/22 but there is no Nop implementation for testing. This is making transition from StatsReporter toCachedStatsReporter
rather difficult. Do we have any plans to provideNopCachedStatsReporter
similar to existingtally.NullStatsReporter
?