Adding tooltip to folium.features.GeoJson from a geopandas dataframe

Question

I am having issues adding tooltips to my folium.features.GeoJson. I can't get columns to display from the dataframe when I select them.

feature = folium.features.GeoJson(df.geometry,
  name='Location',
  style_function=style_function,
  tooltip=folium.GeoJsonTooltip(fields= [df.acquired],aliases=["Time"],labels=True))
  ax.add_child(feature)
  

For some reason when I run the code above it responds with Name: acquired, Length: 100, dtype: object is not available in the data. Choose from: (). I can't seem to link the data to my tooltip.

Answer 1

• have made your code a MWE by including some data
• two key issues with your code
  1. need to pass properties not just geometry to folium.features.GeoJson() Hence passed df instead of df.geometry
  2. folium.GeoJsonTooltip() takes a list of properties (columns) not an array of values. Hence passed ["acquired"] instead of array of values from a dataframe column
• implied issue with your code. All dataframe columns need to contain values that can be serialised to JSON. Hence conversion of acquired to string and drop()

import geopandas as gpd
import pandas as pd
import shapely.wkt
import io
import folium

df = pd.read_csv(io.StringIO("""ref;lanes;highway;maxspeed;length;name;geometry
A3015;2;primary;40 mph;40.68;Rydon Lane;MULTILINESTRING ((-3.4851169 50.70864409999999, -3.4849879 50.7090007), (-3.4857269 50.70693379999999, -3.4853034 50.7081574), (-3.488620899999999 50.70365289999999, -3.4857269 50.70693379999999), (-3.4853034 50.7081574, -3.4851434 50.70856839999999), (-3.4851434 50.70856839999999, -3.4851169 50.70864409999999))
A379;3;primary;50 mph;177.963;Rydon Lane;MULTILINESTRING ((-3.4763853 50.70886769999999, -3.4786112 50.70811229999999), (-3.4746017 50.70944449999999, -3.4763853 50.70886769999999), (-3.470350900000001 50.71041779999999, -3.471219399999999 50.71028909999998), (-3.465049699999999 50.712158, -3.470350900000001 50.71041779999999), (-3.481215600000001 50.70762499999999, -3.4813909 50.70760109999999), (-3.4934747 50.70059599999998, -3.4930204 50.7007898), (-3.4930204 50.7007898, -3.4930048 50.7008015), (-3.4930048 50.7008015, -3.4919513 50.70168349999999), (-3.4919513 50.70168349999999, -3.49137 50.70213669999998), (-3.49137 50.70213669999998, -3.4911565 50.7023015), (-3.4911565 50.7023015, -3.4909108 50.70246919999999), (-3.4909108 50.70246919999999, -3.4902349 50.70291189999999), (-3.4902349 50.70291189999999, -3.4897693 50.70314579999999), (-3.4805021 50.7077218, -3.4806265 50.70770150000001), (-3.488620899999999 50.70365289999999, -3.4888806 50.70353719999999), (-3.4897693 50.70314579999999, -3.489176800000001 50.70340539999999), (-3.489176800000001 50.70340539999999, -3.4888806 50.70353719999999), (-3.4865751 50.70487679999999, -3.4882604 50.70375799999999), (-3.479841700000001 50.70784459999999, -3.4805021 50.7077218), (-3.4882604 50.70375799999999, -3.488620899999999 50.70365289999999), (-3.4806265 50.70770150000001, -3.481215600000001 50.70762499999999), (-3.4717096 50.71021009999998, -3.4746017 50.70944449999999), (-3.4786112 50.70811229999999, -3.479841700000001 50.70784459999999), (-3.471219399999999 50.71028909999998, -3.4717096 50.71021009999998))"""),
           sep=";")

df = gpd.GeoDataFrame(df, geometry=df["geometry"].apply(shapely.wkt.loads), crs="epsg:4326")
df["acquired"] = pd.date_range("8-feb-2022", freq="1H", periods=len(df))

def style_function(x):
    return {"color":"blue", "weight":3}

ax = folium.Map(
    location=[sum(df.total_bounds[[1, 3]]) / 2, sum(df.total_bounds[[0, 2]]) / 2],
    zoom_start=12,
)

# data time is not JSON serializable...
df["tt"] = df["acquired"].dt.strftime("%Y-%b-%d %H:%M")

feature = folium.features.GeoJson(df.drop(columns="acquired"),
  name='Location',
  style_function=style_function,
  tooltip=folium.GeoJsonTooltip(fields= ["tt"],aliases=["Time"],labels=True))
ax.add_child(feature)