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README.md

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+# OpenDTU logger
+
+OpenDTU logger connects to the OpenDTU livedata websocket and captures metrics.
+These metrics are inserted into a PostgreSQL database.
+Optionally, TimescaleDB can be used for better performance.
+
+## Environment variables
+
+```conf
+REMOTE_URL="opendtu:80"
+DB_URL="host=localhost port=5432 user=postgres password=secret dbname=dtu sslmode=disable"
+TIMESCALEDB_ENABLED="true"
+TZ="Europe/Amsterdam"
+```