Changing the attributes of the what appears when hovering over a Choropleth Map in plotly

Question

I am using plotly in Python 3.6.3 and am trying to do a Choropleth map as in here . I would like to change the attributes of what appears when hovering above the map. That is, for example, if we consider the first map and hover of California, it looks like:

I want to change both the font size of the content that appears and the size of the box. Is there a way to access those?

Here is the code that generates it:

import plotly.plotly as py
import pandas as pd

df = pd.read_csv('https://raw.githubusercontent.com/plotly/datasets/master/2011_us_ag_exports.csv')

for col in df.columns:
    df[col] = df[col].astype(str)

scl = [[0.0, 'rgb(242,240,247)'],[0.2, 'rgb(218,218,235)'],[0.4, 'rgb(188,189,220)'],\
            [0.6, 'rgb(158,154,200)'],[0.8, 'rgb(117,107,177)'],[1.0, 'rgb(84,39,143)']]

df['text'] = df['state'] + '<br>' +\
    'Beef '+df['beef']+' Dairy '+df['dairy']+'<br>'+\
    'Fruits '+df['total fruits']+' Veggies ' + df['total veggies']+'<br>'+\
    'Wheat '+df['wheat']+' Corn '+df['corn']

data = [ dict(
        type='choropleth',
        colorscale = scl,
        autocolorscale = False,
        locations = df['code'],
        z = df['total exports'].astype(float),
        locationmode = 'USA-states',
        text = df['text'],
        marker = dict(
            line = dict (
                color = 'rgb(255,255,255)',
                width = 2
            ) ),
        colorbar = dict(
            title = "Millions USD")
        ) ]

layout = dict(
        title = '2011 US Agriculture Exports by State<br>(Hover for breakdown)',
        geo = dict(
            scope='usa',
            projection=dict( type='albers usa' ),
            showlakes = True,
            lakecolor = 'rgb(255, 255, 255)'),
             )

fig = dict( data=data, layout=layout )
py.iplot( fig, filename='d3-cloropleth-map' )

Answer 1

The chloropleth>hoverlabel function lets you set the background color, border color, and font. The size of the border box is determined by the text within it, however. If the name shows up as truncated it can be expanded with the chloropleth>hoverlabel>namelength function.