anishsid/prometheus-es-exporter

Prometheus Elasticsearch Exporter

Prometheus Elasticsearch Exporter

This Prometheus exporter collects metrics from queries run on an Elasticsearch cluster's data, and metrics about the cluster itself.

Query Metrics

The exporter periodically runs configured queries against the Elasticsearch cluster and exports the results as Prometheus gauge metrics.

Values are parsed out of the Elasticsearch results automatically, with the path through the JSON to the value being used to construct metric names.

Metrics are only extracted from aggregation results, with the exception of the query doc count. The keys of any buckets are converted to labels, rather than being inserted into the metric name. See tests/test_parser.py for all the supported queries/metrics.

Cluster Metrics

The exporter periodically queries the Elasticsearch cluster's _cluster/health, _nodes/stats, and _stats endpoints, and exports the results as Prometheus gauge metrics.

Endpoint responses are parsed into metrics as generically as possible so that (hopefully) all versions of Elasticsearch (past and future) can be reasonably supported with the same code. This results in less than ideal metrics in some cases - e.g. redundancy between some metrics, no distinction between gauges and counters (everything's a gauge). If you spot something you think can be reasonably improved let me know via a Github issue (or better yet - a PR).

See tests/test_cluster_health_parser.py, tests/test_nodes_stats_parser.py, and tests/test_indices_stats_parser.py for examples of responses and the metrics produced.

Installation

The exporter requires Python 3 and Pip 3 to be installed.

To install the latest published version via Pip, run:

> pip3 install prometheus-es-exporter

Note that you may need to add the start script location (see pip output) to your PATH.

Usage

Once installed, you can run the exporter with the prometheus-es-exporter command.

By default, it will bind to port 8080, query Elasticsearch on localhost:9200 and run queries configured in a file exporter.cfg in the working directory. You can change these defaults as required by passing in options:

> prometheus-es-exporter -p <port> -e <elasticsearch nodes> -c <path to query config file>

Run with the -h flag to see details on all the available options.

See the provided exporter.cfg file for query configuration examples and explanation.

Docker

Docker images for released versions can be found on Docker Hub (note that no latest version is provided):

> sudo docker pull braedon/prometheus-es-exporter:<version>

To run a container successfully, you will need to mount a query config file to /usr/src/app/exporter.cfg and map container port 8080 to a port on the host. Any options placed after the image name (prometheus-es-exporter) will be passed to the process inside the container. For example, you will need to use this to configure the elasticsearch node(s) using -e.

> sudo docker run --rm --name exporter \
    -v <path to query config file>:/usr/src/app/exporter.cfg \
    -p <host port>:8080 \
    braedon/prometheus-es-exporter:<version> -e <elasticsearch nodes>

If you don't want to mount the query config file in at run time, you could extend an existing image with your own Dockerfile that copies the config file in at build time.

Development

To install directly from the git repo, run the following in the root project directory:

> pip3 install .

The exporter can be installed in "editable" mode, using pip's -e flag. This allows you to test out changes without having to re-install.

> pip3 install -e .

To run tests (as usual, from the root project directory), use:

> python3 -m unittest

Note that these tests currently only cover the response parsing functionality - there are no automated system tests as of yet.

To build a docker image directly from the git repo, run the following in the root project directory:

> sudo docker build -t <your repository name and tag> .

Send me a PR if you have a change you want to contribute!