Local [Germany/Cologne] Water Level of the River Rhein: Parse RESTful JSON Data

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Hello all,

I used the morning to generate more local data for my dashboard. Through the tip of hsch0 I came across the data of the water level of the Rhine. Conveniently, the “Wasserstraßen- und Schifffahrtsverwaltung des Bundes” also offers a nice API with JSON output :wink:

I have not yet worked up all the data in my Lovelace card and am always happy to receive tips and suggestions for improvement.

With the data, notifications about high and low water are of course also very feasible :slight_smile:

Dataset:

  • API Documentation: Here
  • Output: Here
  • Output (more details): Here

Helpful Tools:

Parse RESTful JSON-Data:

sensor:
  - platform: rest
    name: "Pegel Cologne Wasserstand"
    resource: https://www.pegelonline.wsv.de/webservices/rest-api/v2/stations/K%C3%96LN.json?includeTimeseries=true&includeCurrentMeasurement=true
    json_attributes_path: $.timeseries[0].currentMeasurement
    json_attributes:
      - timestamp
      - trend
      - stateMnwMhw
      - stateNswHsw
    value_template: '{{ ( value_json.timeseries[0].currentMeasurement.value | int / 100 ) }}'
    unit_of_measurement: "m"

  - platform: rest
    name: "Pegel Cologne Abfluss"
    resource: https://www.pegelonline.wsv.de/webservices/rest-api/v2/stations/K%C3%96LN.json?includeTimeseries=true&includeCurrentMeasurement=true
    json_attributes_path: $.timeseries[1].currentMeasurement
    json_attributes:
      - timestamp
    value_template: '{{ value_json.timeseries[1].currentMeasurement.value }}'
    unit_of_measurement: "m³/s"

  - platform: rest
    name: "Pegel Cologne Temperatur"
    resource: https://www.pegelonline.wsv.de/webservices/rest-api/v2/stations/K%C3%96LN.json?includeTimeseries=true&includeCurrentMeasurement=true
    json_attributes_path: $.timeseries[2].currentMeasurement
    json_attributes:
      - timestamp
    value_template: '{{ value_json.timeseries[2].currentMeasurement.value }}'
    unit_of_measurement: "°C"

Generating some more Sensors from the data:

sensors:
  - platform: template
    sensors:
      pegel_cologne_wasserstand_trend:
        friendly_name: "Trend"
        value_template: >-
          {% if states.sensor.pegel_cologne_wasserstand.attributes.trend == 1 %}steigend
          {% elif states.sensor.pegel_cologne_wasserstand.attributes.trend == 0 %}gleichbleibend
          {% elif states.sensor.pegel_cologne_wasserstand.attributes.trend == -1 %}fallend
          {% else %}unbekannt{% endif %}
        icon_template: >-
          {% if states.sensor.pegel_cologne_wasserstand.attributes.trend == 1 %}mdi:trending-up
          {% elif states.sensor.pegel_cologne_wasserstand.attributes.trend == 0 %}mdi:trending-neutral
          {% elif states.sensor.pegel_cologne_wasserstand.attributes.trend == -1 %}mdi:trending-down
          {% else %}mdi:water{% endif %}
      
      pegel_cologne_wasserstand_state:
        friendly_name: "Aktuell"
        value_template: >-
          {% if states.sensor.pegel_cologne_wasserstand.attributes.stateMnwMhw == 'low' %}Niedrigwasser
          {% elif states.sensor.pegel_cologne_wasserstand.attributes.stateMnwMhw == 'normal' %}Normal
          {% elif states.sensor.pegel_cologne_wasserstand.attributes.stateMnwMhw == 'high' %}Hochwasser
          {% else %}unbekannt{% endif %}
        icon_template: >-
          {% if states.sensor.pegel_cologne_wasserstand.attributes.stateMnwMhw == 'low' %}mdi:down-up-box
          {% elif states.sensor.pegel_cologne_wasserstand.attributes.stateMnwMhw == 'normal' %}mdi:arrow-right-box
          {% elif states.sensor.pegel_cologne_wasserstand.attributes.stateMnwMhw == 'high' %}mdi:arrow-up-box
          {% else %}mdi:water{% endif %}

      pegel_cologne_wasserstand_schiffahrt:
        friendly_name: "Schiffahrt"
        value_template: >-
          {% if states.sensor.pegel_cologne_wasserstand.attributes.stateNswHsw == 'low' %}Zu wenig Wasser
          {% elif states.sensor.pegel_cologne_wasserstand.attributes.stateNswHsw == 'normal' %}Normal
          {% elif states.sensor.pegel_cologne_wasserstand.attributes.stateNswHsw == 'high' %}Zu viel Wasser
          {% else %}unbekannt{% endif %}
        icon_template: mdi:ferry

homeassistant:
  customize:
    sensor.pegel_cologne_wasserstand:
      friendly_name: Wasserstand
      icon: mdi:arrow-expand-vertical
    sensor.pegel_cologne_abfluss:
      friendly_name: Abfluss
      icon: mdi:water
    sensor.pegel_cologne_temperatur:
      friendly_name: Wassertemperatur
      icon: mdi:coolant-temperature

Lovelace-Code

type: vertical-stack
cards:
  - type: entities
    entities:
      - entity: sensor.pegel_cologne_wasserstand_state
      - entity: sensor.pegel_cologne_wasserstand_trend
      - entity: sensor.pegel_cologne_temperatur
    header:
      type: picture
      image: local/img/header_pegel.png
      tap_action:
        action: none
      hold_action:
        action: none
  - entities:
      - sensor.pegel_cologne_wasserstand
    hour24: true
    name: Wasserstand
    type: 'custom:mini-graph-card'
    hours_to_show: 168
    points_per_hour: 0.5

Lovelace-Card

Unbenannt
Unbenannt622×620 140 KB

Have fun!

9 Likes
2

This is really awesome. Thanks @blackmesa and also thanks to the Wasserstraßen- und Schifffahrtsverwaltung des Bundes for the nice API. Thats a good example of how public money should produce public data. :slight_smile:

3

Thanks, i struggled with the implementation of the data from the city of cologne’ website.
Your datasource is much more detailed and your implementation is a good tutorial!

2 Likes
4

Awesome stuff! I can imagine this being a nice integration, where the pegel that you want to track can be configured via the web interface. Unfortunately, this won’t be feasible to do for myself because I am not really an experienced programmer and have never contributed to Home Assistant before (plus I never have as much time as I have interesting projects in mind, but I suppose we all know that feeling…).

If anyone wants to pursue this someday: I found that there is a “bundesAPI” which offers Python bindings for the pegel-online API: GitHub - bundesAPI/pegel-online-api: Pegelstände der Messstellen des bundesweiten Messstellennetzes der Wasserstraßen- und Schifffahrtsverwaltung des Bundes.
So there is no need to manually parse the JSON data :).

1 Like
5

Thank you! This is amazing :)!

If you live in other cities along the Rhine, be aware that not every measuring station has all the data (e.g. temperature or trend). Took me a while to figure out that that’s the reason why it doesn’t work perfectly for me.

6

Ah, thanks for the tip :slight_smile: