CHANGES (p.prometheus-app.1.4.doc.CHANGES)

v1.4 (2026-08-09)

Core/Lwt split:

Add a new prometheus-lwt metrics package. (@avsm @mtelvers @talex5 #66 #67 #68 #69, reviewed by @dinosaure)
This release is not a breaking change, but instead prepares for deprecation of Lwt in the core package so a future release can remove Lwt from the prometheus core. Users of the core's Lwt-typed functions should migrate to Prometheus_lwt now. Code using the new interface will keep working unchanged in future releases.
Add synchronous variants of the timing helpers to the core. Metric recording is synchronous and these will become the only core timing helpers once the Lwt-typed ones move to prometheus-lwt.
The replacement time-based functions no longer take a gettime argument. Instead, this is provided once by the new Prometheus.init function, which is called automatically when using Prometheus_unix.

To migrate existing code, add a dep on prometheus-lwt and rename following the deprecation warnings from the compiler.

Bug fixes:

Format floats with %.17g (@samoht @talex5 #62). The text exposition formatter printed metric values with %f, so any magnitude below ~5e-7 was reported as 0.000000.

Other changes:

Remove Astring dependency (@talex5 #63).
Remove Asetmap dependency (@talex5 #64). This changes the types of LabelSetMap and MetricFamilyMap slightly, which might affect custom reporters.

v1.3 (2025-12-08)

Make help / type information be OpenMetrics compatible (@Nymphium @tmcgilchrist #47). e.g. using # TYPE rather than #TYPE in the output.
Minor documentation fixes (@tmcgilchrist @vch9 #50 #53).
Make default Makefile target run tests (@talex5 #49).

v1.2 (2022-06-16)

Add lwt collectors and pre-collectors (@killian-delarue, #43). Note that this is a temporary feature while we wait for OCaml 5 to be released, when this can be replaced by the use of effects.
Fix deprecations in Fmt 0.8.10 (@MisterDA, #36).
General build updates, upstream deprecations, etc (@talex5, #33 #34 #35 #40 #42).

v1.1 (2021-06-08)

Allow using a custom formatter for log output (@MisterDA #31). Windows services crash if they try to use stderr.

v1.0 (2020-12-22)

Add logging configuration (#29, @talex5). To configure a server to report counts for log messages:
```
let () = Prometheus_unix.Logging.init ()
```
This installs a reporter that reports the number of messages logged by each log source and at each level. The reporter also displays the timestamp and log source with each message, which is a more suitable configuration for servers.
Add bounds on cohttp to prepare for cohttp 3 release (#28, @talex5).

v0.7 (2020-03-03)

switch float representation to OCaml's default "%f" (#22, @toots)
use Gc.quick_stat for faster stats (#25, @talex5)

v0.6 (2019-11-23)

upgrade build to dune (@talex5)
upgrade to opam2 format (@talex5)

v0.5 (2017-12-20)

prometheus-app: update to cohttp.1.0.0 API (#15, @djs55)
add support for histograms (#14, @stijn-devriendt and @talex5)
add Sample_set module to clean up the API a bit (#13, @talex5)
fix gettimeofday parameter not used in favor of Unix.gettimeofdaya (#12, @stijn-devriendt)

v0.4 (2017-08-02)

unix: update to cohttp >= 0.99.0. Note this means the unix package requires OCaml 4.03+. The main library still only requires OCaml 4.01+

v0.3 (2017-07-03)

Build tweaks to support topkg versioning (@avsm)

v0.2 (2017-05-18)

add example program and update README
switch to jbuilder
throw a clearer error on registering a duplicate metric
use Re rather than Str

v0.1

Initial release.