pachifast-metrics

Prometheus metrics for pachifast (source) projects: an extension package. It adds a GET /metrics endpoint and a middleware that counts and times every request.

Status: alpha. It follows pachifast 0.x: the minor versions of this package may break, and each release works with one minor of pachifast (requires_pachifast).

Install

uv add pachifast-metrics

Then list the module in the project_modules.py of your project (see extending pachifast):

from pachifast.presets import core_module
from pachifast_metrics import module as metrics_module

MODULES = (core_module, metrics_module, ...)

What it exposes

GET /metrics (at the root, not under /api), in the Prometheus text format:

route is the route template (/api/users/{user_id}), never the path with the real id, and a request that matches no route is unmatched: the number of series stays bounded whatever the clients send. The scrape of /metrics is not counted.

Settings

Environment variables, read when the endpoint is called:

Prometheus:

scrape_configs:
  - job_name: myproject
    authorization:
      credentials: <the token>
    static_configs:
      - targets: ["myproject:8000"]

With several workers each process keeps its own counters: scrape every worker (one per port or pod), or put prometheus_client's multiprocess mode behind your server; this package does not do it for you.

Develop

uv sync
uv run pytest -q
uv run ruff check . && uv run ruff format --check .

License

MIT, see LICENSE.

Disclaimer. pachifast-metrics is provided "as is", without warranty of any kind. It is alpha software: it can contain bugs and change incompatibly between minor releases. You are responsible for reviewing, testing and securing the applications you build with it before using them in production.