Prometheus Docker Discovery for single host (no swarm)

Vanilla

Prometheus have built-in discovery of Docker containers with docker_sd_configs, see https://prometheus.io/docs/prometheus/latest/configuration/configuration/#docker_sd_config.

See examples/vanilla for a working example.

This flavour

The trouble with docker_sd_configs is when a container have multiple exposed ports, there will be multiple targets present for the same container. This application solves that scenario.

See examples/discovery for a working example.

For a container to be exported:

• add container label 'prometheus_job' with the job name you want as value.
• the container must be in the configured target network (defaults to 'metrics-net').
• the container must have at least 1 expose port. Public ports are ignored. This may already be set in the Docker image.

Container label	Description
prometheus_job	Add target. Set job name to value. Containers without this label will be ignored.
prometheus_<key>	Add <key>' to output labels
prometheus_scrape_port	Overrules address scrape port. Should be set when the container have multiple exposed ports.
prometheus_scrape_interval	Override the scrape interval. Optional.
prometheus_scrape_timeout	Override the scrape timeout. Optional.
prometheus_scrape_path	Override metrics path. Optional.
prometheus_scrape_scheme	Override scheme. Optional.

Metrics should indicate if a container has the 'prometheus_job' label set, but not included in targets.