Prometheus Catalog

Simple service that keeps list of prometheus scrape targets in redis. The service allows servers to self-register for monitoring and prometheus to query the list of self-registered scrape targets.

Service can be used as sidecar container or standalone service.

$FILE_SD_CONFIG file can be used to directly integrate into Prometheus' scrape config, either by mounting the file to Prometheus container or as a sidecar container.

As a standalone service, cronjob can be used to periodically fetch with http://<prometheus-catalog-host>/list API call, format of the content matches $FILE_SD_CONFIG file.

Usage

docker run -p 5000:80 -v $(pwd)/state:/var/prometheus-catalog -ti --rm eficode/prometheus-catalog:latest

Environment variables

• DB_FILE: Json database file name, use volume for persistence. Default: /var/prometheus-catalog/db.json
• TIME_TO_LIVE: Registered entry expiration time in seconds. Default is 1 day
• FILE_SD_CONFIG: Prometheus file-based service discovery, file can be used as is, therefore it can be mounted directly to Prometheus container. File is rewritten on every API change. Default: /var/prometheus-catalog/file_sd_config.json

API

Register

Example for registering:

curl -d'{"labels":{"job":"nodes"},"targets":["node.some-domain.com:9100"],"hostname":"some-domain.com"}' -H'Content-Type: application/json' http://127.0.0.1:5000/register

If the metrics route is not "/metrics", but something else:

curl -d'{"labels":{"job":"nodes","__metrics_path__":"/some-metrics"},"targets":["node.some-domain.com:9100"],"hostname":"some-domain.com"}' -H'Content-Type: application/json' http://127.0.0.1:5000/register

The subsequent registrations with same hostname, will update/add labels and/or add targets. For removing labels or targets, you need to unregister first and then do the register again with correct values. API will return Bad Request if the entry with same labels and targets already exist, regardless of hostname value.

Unregister

curl -XDELETE http://127.0.0.1:5000/unregister/some-domain.com

List

curl http://127.0.0.1:5000/list

Metrics

curl http://127.0.0.1:5000/metrics

Health

curl http://127.0.0.1:5000/healthz

Develop

virtualenv .
pip install -r requirements.txt
bin/python app/__init__.py

API will be available at port 5000, also note that entry expiration will not work when running without uwsgi

Links

Prometheus file-based service discovery file