Store OpenTelemetry metrics using Telegraf and CrateDB

This how-to guide walks you through configuring Telegraf to receive OpenTelemetry metrics and store them into CrateDB.

Prerequisites

Use Docker or Podman to run all components. This approach works consistently across Linux, macOS, and Windows.

Files

First, download and save all required files to your machine.

• .env

• compose.yaml

• example.py

• telegraf.conf

Services

Start services using Docker Compose or Podman Compose. If you use Podman, replace docker with podman (or enable the podman‑docker compatibility shim) and run podman compose up.

docker compose up

Submit data

Use Python

To submit metrics using the OpenTelemetry Python SDK, choose one of these approaches:

Option 1: Using uv (recommended)

docker compose run --rm --env-from-file=.env uv uv run --with=opentelemetry-distro --with=opentelemetry-exporter-otlp opentelemetry-instrument python /src/example.py

Option 2: Using pip

First, install dependencies:

pip install opentelemetry-distro opentelemetry-exporter-otlp

Then run the example:

opentelemetry-instrument --service_name=app python example.py

Display example.py

# OpenTelemetry demo application.
# https://cratedb.com/docs/guide/integrate/opentelemetry/
from opentelemetry import metrics


def main():

    meter = metrics.get_meter("testdrive.meter.name")
    temperature = meter.create_gauge("temperature")
    humidity = meter.create_gauge("humidity")

    temperature.set(42.42)
    humidity.set(84.84)


if __name__ == "__main__":
    main()

Use any language

Use any of the available OpenTelemetry language APIs & SDKs for C++, C#/.NET, Erlang/Elixir, Go, Java, JavaScript, PHP, Python, Ruby, Rust, or Swift.

Explore data

CrateDB stores the metrics in the designated table, ready for inspection and analysis.

docker compose exec cratedb crash -c "SELECT * FROM doc.metrics ORDER BY timestamp LIMIT 5;"

+---------------------+---------------+-------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------+---------------+
|             hash_id |     timestamp | name        | tags                                                                                                                                                                                                                                           | fields           |           day |
+---------------------+---------------+-------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------+---------------+
| 4549776513022193265 | 1758500094846 | temperature | {"host": "2805bf17ee55", "otel_library_name": "testdrive.meter.name", "service_name": "app", "telemetry_auto_version": "0.58b0", "telemetry_sdk_language": "python", "telemetry_sdk_name": "opentelemetry", "telemetry_sdk_version": "1.37.0"} | {"gauge": 42.42} | 1758499200000 |
| -926134856403504308 | 1758500094846 | humidity    | {"host": "2805bf17ee55", "otel_library_name": "testdrive.meter.name", "service_name": "app", "telemetry_auto_version": "0.58b0", "telemetry_sdk_language": "python", "telemetry_sdk_name": "opentelemetry", "telemetry_sdk_version": "1.37.0"} | {"gauge": 84.84} | 1758499200000 |
+---------------------+---------------+-------------+------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+------------------+---------------+
SELECT 2 rows in set (0.049 sec)