Fixes#1127.
If a native histogram has no observations and a zero threshold of
zero, then it is indistinguishable from a classic histogram. To give
scrapers a hint that it is indeed a native histogram, we add a no-op
span.
This needs follow-up PRs in prometheus/prometheus and
prometheus/client_model.
Signed-off-by: beorn7 <beorn@grafana.com>
The current code doesn't work fork negative schemas if the observed
value should go into a bucket with a non-positive key.
Signed-off-by: beorn7 <beorn@grafana.com>
This replaces usage of proto.{Float64,Int32,Int64,String,Uint32,Uint64},
which doesn't break the interface.
And remove usage of proto.MarshalTextString in wrap_test.go
Updates: #1175
Signed-off-by: Shengjing Zhu <zhsj@debian.org>
Signed-off-by: Shengjing Zhu <zhsj@debian.org>
* Introduce MetricVecOpts and add constraints to VariableLabels
MetricVecOpts exposes options specific to MetricVec initialisation. The
first option exposed by MetricVecOpts are constraints on VariableLabels,
allowing restrictions on the possible values a label can take, to
prevent cardinality explosion when the label value comes from a
non-trusted source (as a user input or HTTP header).
Signed-off-by: Quentin Devos <4972091+Okhoshi@users.noreply.github.com>
* Add tests
Signed-off-by: Quentin Devos <4972091+Okhoshi@users.noreply.github.com>
Signed-off-by: Quentin Devos <4972091+Okhoshi@users.noreply.github.com>
This intends to avoid confusing users by the subtle difference between
a native histogram and a sparse bucket.
Signed-off-by: beorn7 <beorn@grafana.com>
NaN observations now go to no bucket, but increment count (and
effectively set sum to NaN, too).
±Inf observations now go to the bucket following the bucket that would
have received math.MaxFloat64. The former is now the last bucket that
can be created.
The getLe is modified to return math.MaxFloat64 for the penultimate
possible bucket.
Also add a test for getLe.
Signed-off-by: beorn7 <beorn@grafana.com>
Note that this is an incompatible change. To scrape this new format,
the Prometheus server needs to be updated at the same time. PR
incoming.
Signed-off-by: beorn7 <beorn@grafana.com>
* Add support for exemplars on constHistogram
Co-authored-by: William Perron <william.perron@shopify.com>
Signed-off-by: William Perron <william.perron@shopify.com>
* remove GetExemplars function
Signed-off-by: William Perron <william.perron@shopify.com>
* fixed linting warnings
reduce repetition in constHistogram w/ exemplar
Signed-off-by: William Perron <william.perron@shopify.com>
* Add values to correct bucket
Signed-off-by: William Perron <william.perron@shopify.com>
* Misc fixes
Co-authored-by: Francis Bogsanyi <francis.bogsanyi@shopify.com>
Signed-off-by: William Perron <william.perron@shopify.com>
* avoid panic when there are fewer buckets than exemplars
Co-authored-by: Arun Mahendra <arun.mahendra@shopify.com>
Signed-off-by: William Perron <william.perron@shopify.com>
* Added MustNewMetricWithExemplars that wraps metrics with exemplar (#3)
Changes:
* Make sure to not "leak" dto.Metric
* Reused upper bounds we already have for histogram
* Common code for all types.
Signed-off-by: Bartlomiej Plotka <bwplotka@gmail.com>
Co-authored-by: Arun Mahendra <arun.mahendra@shopify.com>
Co-authored-by: Bartlomiej Plotka <bwplotka@gmail.com>
This function calculates exponential buckets with different arguments
than the existing ExponentialBuckets function. Instead of specifying the
start and factor, the user can specify the min and max bucket value. We
have been doing it this way internally at my company for some time.
Signed-off-by: Seth Bunce <seth.bunce@getcruise.com>
This seem what OTel is converging towards, see
https://github.com/open-telemetry/oteps/pull/149 .
I see pros and cons with base-10 vs base-2. They are discussed in
detail in that OTel PR, and the gist of the discussion is pretty much
in line with my design doc. Since the balance is easy to tip here, I
think we should go with base-2 if OTel picks base-2. This also seems
to be in agreement with several proprietary solution (see again the
discussion on that OTel PR.)
The idea to make the number of buckets per power of 2 (or formerly 10)
a power of 2 itself was also sketched out in the design doc
already. It guarantees mergeability of different resolutions. I was
undecided between making it a recommendation or mandatory. Now I think
it should be mandatory as it has the additional benefit of playing
well with OTel's plans.
This commit also addresses a number of outstanding TODOs.
Signed-off-by: beorn7 <beorn@grafana.com>
MetricVec was already exported in early versions of this library, but
nobody really used it to implement vectors of custom Metric
implementations. Now #796 has shown up with a fairly special use case
for which I'd prefer a custom implementation of a special
"auto-sampling histogram" outside of this library. Therefore, I'd like
to reinstate support for creating vectors of custom Metric
implementations.
I played around for quite some while with the option of a separate
package providing the tools one would need to create vectors of custom
Metric implementations. However, with the current structure of the
prometheus/client_golang/prometheus package, this leads to a lot of
complications with circular dependencies. (The new package would need
the primitives from the prometheus package, while the existing metric
vectors like GaugeVec need to import the new vector package to not
duplicate the implementation. Separating vector types from the main
prometheus package is out of the question at this point because that
would be a breaking change.)
Signed-off-by: beorn7 <beorn@grafana.com>
`github.com/golang/protobuf/proto` is deprecated in lieu of
`google.golang.org/protobuf/proto`. However, we cannot simply
migrate. Types from the proto package are exposed to users of packages
in this repo. If we migrate here, users have to migrate to. Thus, we
could only migrate with a major version bump.
In different news, with all the inline lint:ignore comments, including
the existing ones, there is no need to repeat the exception in the
Makefile.
A current version of `staticcheck` is happy with the code after this
commit. golangci-lint is broken at the moment, however, and ignores
the lint:ignore comments in the code as well as those via envvar.
Signed-off-by: beorn7 <beorn@grafana.com>
This is, sadly, the only way to avoid a breaking change. The cost is
that anyone using exemplars has to perform a type assertion. This is,
however, a common pattern where interfaces turn out to need additional
methods in a stable library or only some implementations can provide
the additional methods (AKA "interface upgrade").
Needless to say that in v2 of this library, we'll do things in a more
straight forward way.
Signed-off-by: beorn7 <beorn@grafana.com>
Bartlomiej Plotka