Autometrics

The [Autometrics specification v1.0.0](https://github.com/autometrics-dev/autometrics-shared/blob/main/specs/autometrics_v1.0.0.md) has been released.
The following changes are made in order to bring the release in compliance with the spec:

- Added `repository.url` and `repository.provider` as `build_info` labels. They can be
configured either through environment variables or automatically based on your `Cargo.toml`
`package.repository` value (only GitHub, GitLab and BitBucket) (152)
- Added `autometrics.version` as `build_info` label, specifying the autometrics spec
version that we are targeting. It is currently hardcoded to `1.0.0` (154)
- Environment variables for `repository.url` and `repository.provider` will now be read at
both compile time and runtime (156)

[0.6.0](https://github.com/autometrics-dev/autometrics-rs/releases/tag/v0.5.0) - 2023-08-08

Added

- Autometrics settings can now be configured via `settings::AutometricsSettings::builder()`
- A custom `Registry` can be used to collect metrics. This may be used to add
custom metrics alongside those produced by Autometrics, as well as to export
the metrics without using the provided `prometheus_exporter`
- All metrics now have a `service.name` label attached. This is set via the settings,
via runtime environment variable (`AUTOMETRICS_SERVICE_NAME` or `OTEL_SERVICE_NAME`),
or it falls back to the crate name defined in the `Cargo.toml`
- Function counters are initialized to zero in debug builds. This exposes details of
instrumented functions to Prometheus and visualization tools built on top of it,
before the functions have been called.
- Basic benchmarking

Changed

- Renamed the `function.calls.count` metric to `function.calls` (which is exported
to Prometheus as `function_calls_total`) to be in line with OpenTelemetry and
OpenMetrics naming conventions. **Dashboards and alerting rules must be updated.**
- When the `function.calls.duration` histogram is exported to Prometheus, it now
includes the units (`function_calls_duration_seconds`) to be in line with
Prometheus/OpenMetrics naming conventions. **Dashboards and alerting rules must be updated.**
- Struct methods now have the struct name as part of the `function` label on the metrics
(for example, `MyStruct::my_method`)
- The `caller` label on the `function.calls` metric was replaced with `caller.function`
and `caller.module`
- The `custom-objective-latency` feature can now be used with the `prometheus-exporter`, as well
as with the `prometheus` and `prometheus-client` crates, because the histogram buckets can now
be configured via the settings
- Upgraded `opentelemetry` to v0.20

Deprecated

- `metrics` feature flag (replaced with `metrics-0_21`)
- `opentelemetry` feature flag (replaced with `opentelemetry-0_20`)
- `prometheus` feature flag (replaced with `prometheus-0_13`)
- `prometheus-client` feature flag (replaced with `prometheus-client-0_21`)
- `exemplars-tracing-opentelemetry` feature flag (replaced with `exemplars-tracing-opentelemetry-0_20`)

Removed

- `encode_global_metrics` was removed and replaced by `prometheus_exporter::encode_to_string`
- `global_metrics_exporter` was removed and replaced by `prometheus_exporter::init`
- `backends::prometheus_client::REGISTRY` was removed. The `Registry` used with the `prometheus-client`
backend can now be accessed via `AutometricsSettings::prometheus_client_registry`

Fixed

- Return types on functions annotated with `[autometrics]` containing generic
`impl` types in their type arguments (`fn() -> Result<impl ToString, impl std::error::Error>`)
no longer fail to compile.

[0.5.0](https://github.com/autometrics-dev/autometrics-rs/releases/tag/v0.5.0) - 2023-06-02

Added

- Support the official `prometheus-client` crate for producing metrics
- Support exemplars when using the feature flags `exemplars-tracing` or `exemplars-tracing-opentelemetry`.
Autometrics can now extract fields from the current span and attach them as exemplars on the
counter and histogram metrics
- `ResultLabels` derive macro allows to specify on an enum whether variants should
always be "ok", or "error" for the success rate metrics of functions using them. (61)
- The `prometheus_exporter` module contains all functions related to the `prometheus-exporter` feature
- `prometheus_exporter::encode_http_response` function returns an `http::Response` with the metrics.
This is especially recommended when using exemplars, because it automatically uses the OpenMetrics
`Content-Type` header, which is required for Prometheus to scrape metrics with exemplars
- `AUTOMETRICS_DISABLE_DOCS` environment variable can be set to disable doc comment generation
(this is mainly for use with editor extensions that generate doc comments themselves)

Changed

- Users must configure the metrics library they want to use autometrics with, unless the
`prometheus-exporter` feature is enabled. In that case, the official `prometheus-client` will be used
- Metrics library feature flags are now mutually exclusive (previously, `autometrics` would only
produce metrics using a single metrics library if multiple feature flags were enabled, using
a prioritization order defined internally)
- `GetLabels` trait (publicly exported but meant for internal use) changed the signature
of its function to accomodate the new `ResultLabels` macro. This change is not significant
if you never imported `autometrics::__private` manually (61)
- When using the `opentelemetry` together with the `prometheus-exporter`, it will no longer
use the default registry provided by the `prometheus` crate. It will instead use a new registry
- Updated `opentelemetry` dependencies to v0.19. This means that users using autometrics
with `opentelemetry` but not using the `prometheus-exporter` must update the `opentelemetry`
to use v0.19.

Deprecated
- `global_metrics_exporter` and `encode_global_metrics` have been deprecated and replaced by
`prometheus_exporter::init` and `prometheus_exporter::encode_to_string`, respectively

Removed

- `opentelemetry` is no longer used by default
- `GetLabelsForResult` trait (publicly exported but meant for internal use) was removed
to accomodate the new `ResultLabels` macro. This change is not significant
if you never imported `autometrics::__private` manually (61)

Fixed

- `[autometrics]` now works on functions that use type inference in their return statement
(74, 61)

[0.4.1](https://github.com/autometrics-dev/autometrics-rs/releases/tag/v0.4.1) - 2023-05-05

Changed

- Overhaul documentation

Fixed

- Generated latency query needs additional labels to show lines for 95th and 99th percentiles

[0.4.0](https://github.com/autometrics-dev/autometrics-rs/releases/tag/v0.4.0) - 2023-04-26

Added

- `build_info` metric tracks software version and commit
- Queries now use `build_info` metric to correlate version info with problems

Fixed

- Prometheus rules handle when the counter metric name has a `_total` suffix

[0.3.3](https://github.com/autometrics-dev/autometrics-rs/releases/tag/v0.3.3) - 2023-04-14

Added

- Alerts have minimum traffic threshold of 1 request / minute

Fixed

- Latency SLO total query in alerting rules

[0.3.1](https://github.com/autometrics-dev/autometrics-rs/releases/tag/v0.3.1) - 2023-03-21

Added

- `custom-objective-latency` and `custom-objective-percentile` feature flags

Changed

- Use the OpenTelemetry default histogram buckets

Removed

- Remove the latency objective values for 150, 200, and 350 milliseconds
- `custom-objectives` feature flag

[0.3.0](https://github.com/autometrics-dev/autometrics-rs/releases/tag/v0.3.0) - 2023-03-14

Added

- Support defining Service-Level Objectives (SLOs) in code
- CLI to generate Sloth file, which is then used to generate Prometheus alerting rules
- `[skip_autometrics]` annotation when applying autometrics to an `impl` block
- `ok_if` and `error_if` autometrics parameters

[0.2.4](https://github.com/autometrics-dev/autometrics-rs/releases/tag/v0.2.4) - 2023-02-08

Fixed

- Histogram buckets


[0.2.3](https://github.com/autometrics-dev/autometrics-rs/releases/tag/v0.2.3) - 2023-01-31

Fixed

- Building of documentation on docs.rs

[0.2.0](https://github.com/autometrics-dev/autometrics-rs/releases/tag/v0.2.0) - 2023-01-31

Added

- Support `opentelemetry` and `metrics` crates for tracking metrics
- Support applying autometrics to an `impl` block

Changed

- Tracking function concurrency is optional

[0.1.1](https://github.com/autometrics-dev/autometrics-rs/releases/tag/v0.1.1) - 2023-01-27

Added

- Track concurrent requests
- Add return types as labels
- Separate function call counter
- `caller` label

Changed

- Use OpenTelemetry metric naming conventions

Added

- Added support for `record_error_if` and `record_success_if`
- Added OTLP exporters for OpenTelemetry tracker (89)
- Added `repository_url` and `repository_provider` labels to `build_info` (97)
- Added `autometrics.version` label to `build_info` (101)

Changed

- [💥 Breaking change] `init` function is now required to be called before using autometrics (89)
- Prometheus exporters are now configured via `init` function (89)
- Updated examples to call `init` function (94)
- Updated `docker compose` / `tilt` config in repo to include grafana with our dashboards (94)
- `Objective`s will now emit a warning when name contains characters other than alphanumeric and dash (99)

Security

- Updated FastAPI and Pydantic dependencies in the examples group (89)
- Updated dependencies in dev and examples groups (97)

[0.9](https://github.com/autometrics-dev/autometrics-py/releases/tag/0.9) - 2023-09-24

Added

- Added the `start_http_server`, which starts a separate HTTP server to expose
the metrics instead of using a separate endpoint in the existing server. (77)
- Added the `init` function that you can use to configure autometrics. (77)

Changed

- Renamed the `function.calls.count` metric to `function.calls` (which is exported
to Prometheus as `function_calls_total`) to be in line with OpenTelemetry and
OpenMetrics naming conventions. **Dashboards and alerting rules must be updated.** (74)
- When the `function.calls.duration` histogram is exported to Prometheus, it now
includes the units (`function_calls_duration_seconds`) to be in line with
Prometheus/OpenMetrics naming conventions. **Dashboards and alerting rules must be updated.** (74)
- The `caller` label on the `function.calls` metric was replaced with `caller.function`
and `caller.module` (75)
- All metrics now have a `service.name` label attached. This is set via runtime environment
variable (`AUTOMETRICS_SERVICE_NAME` or `OTEL_SERVICE_NAME`), or falls back to the package name. (76)
- In case of running a script outside of module, the `module` label is now set to file name (80)

Security

- Updated dependencies in examples group (77)

[0.8](https://github.com/autometrics-dev/autometrics-py/releases/tag/0.8) - 2023-07-24

Added

- Support for prometheus-client 0.17.x

[0.7](https://github.com/autometrics-dev/autometrics-py/releases/tag/0.7) - 2023-07-19

Added

- Initialize counter metrics at zero 54

Changed

- Caller tracking only tracks autometricised functions, as per spec 59
- Function name labels now use qualified name, and module labels use module's `__name__` when available 59

Deprecated

-

Removed

-

Fixed

- Fixed calculation of funciton duration when using OpenTelemetry tracker 66

Security

-

[0.6](https://github.com/autometrics-dev/autometrics-py/releases/tag/0.6) - 2023-06-23

Added

- Exemplars support (51)
- Optional concurrency tracking support (55)

Changed

- `build_info` is extended with support for branch labels and now picks up the commit label from `COMMIT_SHA` env var (52)

Fixed

- Fixed decorator async function handling (55)

Security

- Update requests, starlette, fastapi dependencies used by the examples

[0.5](https://github.com/autometrics-dev/autometrics-py/releases/tag/0.5) - 2023-05-11

Added

- Support `build_info` metrics for Prometheus tracker (35)
- **NOTE**: The OpenTelemetry tracker does not accurately track `build_info`, so you will need to set the env var `AUTOMETRICS_TRACKER=PROMETHEUS` to see accurate build info in your metrics (see 38)
- OpenTelemetry Support (28)
- Fly.io example (26)
- Django example (22)

Fixed

- The `autometrics` decorator now supports async functions (33)

[0.4](https://github.com/autometrics-dev/autometrics-py/releases/tag/0.4) - 2023-04-13

Added

- SLO Support (16)
- Improved documentation and examples (13 19)

Changed

- Development setup (10 12)

Fixed

- Issue with trailing slashes in prometheus url (14)

[0.3](https://github.com/autometrics-dev/autometrics-py/releases/tag/0.3) - 2023-03-28

Added

- Implemented caller label for the function calls counter (9)


Changelog

All notable changes to this project will be documented in this file.

The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).

---

[Unreleased]

Breaking changes

- `opentelemetry` has been updated to v0.21 (159)
New feature flags: `opentelemetry-0_21`, `exemplars-tracing-opentelemetry-0_22`
Removed feature flags: `opentelemetry-0_20`, `exemplars-tracing-opentelemetry-0_20`, `exemplars-tracing-opentelemetry-0_21`
- `prometheus-client` has been updated to v0.22 (160)
New feature flag: `prometheus-client-0_22`
Removed feature flag: `prometheus-client-0_21`

**If you are using these metrics separately in your application in addition to Autometrics,
ensure that you match the version that Autometrics uses.**

General changes

- New exporter, `otel_push_exporter` is now available in addition to the existing
`prometheus_exporter`. It can be used to push metrics in the OTEL format via
HTTP or gRPC to a OTEL-collector-(compatible) server.
- Update to `syn` v2 (145)
- Add support for tracing-opentelemetry v0.21 (147)
- Error messages when using `[autometrics]` together with `[async_trait]`
has been improved (149)
- Fixed missing feature flag for `opentelemetry-otlp` when autometrics feature
`otel-push-exporter` is enabled
- Fixed incorrect duration being recorded when using `[async_trait]` together with `[autometrics]` (161)
**Please note that the `[autometrics]` macro needs to be defined BEFORE `[async_trait]`.**
- Fixed value of the `result` label being empty when the function is annotated with `[async_trait]` (161)