Skip to content

feat(om1.1): relax the requirements around unit and total suffixes #2750

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 3 commits into from
Oct 8, 2025
Merged

feat(om1.1): relax the requirements around unit and total suffixes #2750

Changes from all commits
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
d2162a6
feat(om1.1): relax the requirements around unit and total suffixes
krajorama Oct 2, 2025
86c97ac
Update docs/specs/om/open_metrics_spec_1_1.md
krajorama Oct 3, 2025
b8b4372
fix example format
krajorama Oct 6, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
20 changes: 16 additions & 4 deletions docs/specs/om/open_metrics_spec_1_1.md
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -144,7 +144,9 @@ Type specifies the MetricFamily type. Valid values are "unknown", "gauge", "coun

##### Unit

Unit specifies MetricFamily units. If non-empty, it MUST be a suffix of the MetricFamily name separated by an underscore. Be aware that further generation rules might make it an infix in the text format.
Unit specifies MetricFamily units. If non-empty, it SHOULD be a suffix of the MetricFamily name separated by an underscore. Be aware that further generation rules might make it an infix in the text format.

Be aware that exposing metrics without the unit being a suffix of the MetricFamily name directly to end-users may reduce the usability due to confusion about what the metric's unit is.

##### Help

Expand Down Expand Up @@ -479,7 +481,7 @@ There are four pieces of metadata: The MetricFamily name, TYPE, UNIT and HELP.

If no TYPE is exposed, the MetricFamily MUST be of type Unknown.

If a unit is specified it MUST be provided in a UNIT metadata line. In addition, an underscore and the unit MUST be the suffix of the MetricFamily name.
If a unit is specified it MUST be provided in a UNIT metadata line. In addition, an underscore and the unit SHOULD be the suffix of the MetricFamily name.

A valid example for a foo_seconds metric with a unit of "seconds":

Expand All @@ -488,7 +490,7 @@ A valid example for a foo_seconds metric with a unit of "seconds":
# UNIT foo_seconds seconds
```

An invalid example, where the unit is not a suffix on the name:
A valid, but discouraged example, where the unit is not a suffix on the name:

```
# TYPE foo counter
Expand Down Expand Up @@ -633,7 +635,9 @@ foo 18.0 456

##### Counter

The MetricPoint's Total Value Sample MetricName MUST have the suffix `_total`. If present the MetricPoint's Created Value Sample MetricName MUST have the suffix `_created`.
The MetricPoint's Total Value Sample MetricName SHOULD have the suffix `_total`. If present the MetricPoint's Created Value Sample MetricName MUST have the suffix `_created`.
Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

hmmm, I'm not sure how Otel deals with created metrics. I am tempted not to have any MUSTs around names so that we can truly allow anything and not be against the spec (no matter how much we discourage it)

Copy link
Contributor

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I think we need a MUST for the _created series, otherwise it wouldn't be the _created series :).


Be aware that exposing metrics without `_total` being a suffix of the MetricFamily name directly to end-users may reduce the usability due to confusion about what the metric's type is.

An example with a Metric with no labels, and a MetricPoint with no timestamp and no created:

Expand Down Expand Up @@ -665,6 +669,14 @@ foo_total 17.0 1520879607.789
foo_created 1520430000.123 1520879607.789
```

An example with a Metric with no labels, and a MetricPoint without the `_total` suffix and with a timestamp and a created:

```openmetrics-add-eof
# TYPE foo counter
foo 17.0 1520879607.789
foo_created 1520430000.123 1520879607.789
```

Exemplars MAY be attached to the MetricPoint's Total sample.

##### StateSet
Expand Down