exporter_proxy

A small pure-python Reverse HTTP proxy for Prometheus exporters with TLS support.

Installation

exporter_proxy can be downloaded and run as a standalone script. setup.py is provided for simplifying package builds.

Since it is pure-python, exporter_proxy should run on any OS with Python built with SSL support. It has been tested on Linux and Windows.

Use

exporter_proxy --help
usage: exporter_proxy [-h] [-c CONFIG]

Command-line options

optional arguments:
  -h, --help            show this help message and exit
  -c CONFIG, --config CONFIG
                        Path to config file. (Defaults to: /etc/prometheus/exporter_proxy.ini)

Configuration

The configuration is held in an ini-file. The section title must be [exporter_proxy]. See config.ini as an example.

The following configuration options are available:

• proxy_address - The address to bind the proxy listener to.
• proxy_port - The port to bind the proxy listener to.
• server_url - The URL (optionally including port) of the server to proxy.
• ssl_cert - Path to file containing the public certificate or chain for the proxy server (optional - if set enables SSL).
• ssl_key - Path to file containing the certificate key for the proxy server. (optional, if key is in the certfile).
• ssl_verify - Should client certificate verification be performed. (optional).
• ssl_clients - A space-separated list of allowed clients. Matches entries in the client certificate subjectAltName field (optional - requires ssl_verify to be set).

Prometheus

The documentation on configuring Prometheus to scrape using TLS is here: https://prometheus.io/docs/prometheus/latest/configuration/configuration/#tls_config

TLS is configured separately for each scrape job:

scrape_configs:
  - job_name: node
    scheme: https
    tls_config:
        cert_file: /etc/prometheus/exporter_proxy.crt
        key_file: /etc/prometheus/exporter_proxy.key
    file_sd_configs:
    - files:
      - /etc/prometheus/targets.d/node_targets.json

Multiple Exporters

exporter_proxy@.service is an example systemd 'instance' service that will start an instance of exporter_proxy by loading a config file based on the instance name.

For example systemctl start exporter_proxy@node would run using the config in /etc/prometheus/exporter_proxy/node.ini