Initial commit

.gitignore

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+.vscode/
+__pycache__/
+.pyenv/

Dockerfile

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+FROM python:3.8-slim-buster
+
+# Keeps Python from generating .pyc files in the container
+ENV PYTHONDONTWRITEBYTECODE 1
+
+# Turns off buffering for easier container logging
+ENV PYTHONUNBUFFERED 1
+
+ADD requirements.txt .
+RUN python -m pip install -r requirements.txt
+
+WORKDIR /app
+COPY main.py /app
+
+RUN useradd appuser && chown -R appuser /app
+USER appuser
+
+EXPOSE 5000
+
+ENTRYPOINT ["python", "main.py"]

main.py

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+"""
+Present observational weather data to Prometheus
+"""
+
+import json
+import time
+import os
+
+import requests
+from flask import Flask, Response
+
+app = Flask(__name__)
+
+
+def fetch_metoffice_data(location: int, apikey: str) -> dict:
+    """
+    Fetch current data from the Met Office for the provided postcode
+    """
+
+    obs_data = requests.get(
+        f'http://datapoint.metoffice.gov.uk/public/data/val/wxobs/all/json/{location}?'
+        f'key={apikey}&'
+        'res=hourly'
+    )
+
+    return json.loads(obs_data.content)
+
+
+@app.route('/metrics')
+def metrics():
+    """
+    Output Prometheus-style metrics
+    """
+    metoff_apikey = os.environ.get('METOFF_APIKEY')
+    metoff_location = os.environ.get('METOFF_LOCATION')
+
+    hour_data = fetch_metoffice_data(metoff_location, metoff_apikey,)['SiteRep']['DV'][
+        'Location'
+    ]['Period'][-1]['Rep'][time.gmtime().tm_hour]
+
+    ret_data = [
+        {
+            'key': 'sensor_weather_outdoor_temperature_celcius',
+            'labels': {
+                'location': metoff_location,
+            },
+            'type': 'gauge',
+            'value': float(hour_data['T']),
+        },
+        {
+            'key': 'sensor_weather_outdoor_humidity_percent',
+            'labels': {
+                'location': metoff_location,
+            },
+            'type': 'gauge',
+            'value': float(hour_data['H']),
+        },
+    ]
+
+    ret_str = ''
+    for item in ret_data:
+        ret_str += f'# TYPE {item["key"]} {item["type"]}\r\n'
+        ret_str += f'{item["key"]} {item["value"]}\r\n'
+
+    resp = Response(ret_str)
+    resp.headers['Content-type'] = 'text/plain'
+
+    return resp
+
+
+if __name__ == '__main__':
+    app.run(host='0.0.0.0')

requirements.txt

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+flask
+requests