Invalid Zoom for TileLayer in version 0.19.0

[pmd84]

I'm using a tiling endpoint based of TiTiler to serve map tiles on Folium. Since the upgrade last night, the tiles no longer render, and my tiling endpoint gives me this error: "Invalid ZOOM level 0", and the tile request is showing as "tiles/WebMercatorQuad/0/0/0"

geom = shape(AOI)
centroid = geom.centroid

m = folium.Map(location=[centroid.y, centroid.x], zoom_start=12)

# Initialize Tile Layer and add to map
TileLayer(
    tiles=tilejson["tiles"][0],
    opacity=1,
    min_zoom=8,
    max_zoom=14,
    attr="Sentinel-2 COG",
).add_to(m)

folium.GeoJson(AOI).add_to(m)

m

Typically, the folium map generates tile at whatever x, y, z are visible on the map. Only this single 0,0,0 tile is being requested.

Environment is in a Databricks notebook with Folium 0.19.0

[lux-orc]

I have got a similar issue, the following is the reproducible codes that people can test on folium 0.18.0 and 0.19.0.

import folium

# Esri_WorldTopoMap
arcgis = 'https://server.arcgisonline.com/ArcGIS/rest/services'
esri = {'Esri_WorldTopoMap': 'World_Topo_Map'}
tile = 'MapServer/tile/{z}/{y}/{x}'
tile_esri = dict(zip(esri.keys(), ['/'.join([arcgis, v, tile]) for v in esri.values()]))

# GOOGLE online map
tile_google = {
    'Maps': 'https://mt1.google.com/vt/lyrs=r&x={x}&y={y}&z={z}',
    'Satellite': 'http://www.google.cn/maps/vt?lyrs=s@189&gl=cn&x={x}&y={y}&z={z}',
    'Roads': 'https://mt1.google.com/vt/lyrs=h&x={x}&y={y}&z={z}',
}

m = folium.Map(
    location=(-45.54, 169.74),
    tiles=None,
    zoom_start=9,
    zoom_control=False,
    attributionControl=False,
)

# Add 'Esri_WorldTopoMap' as 'Esri_WorldTopoMap'
folium.raster_layers.TileLayer(
    tiles=tile_esri['Esri_WorldTopoMap'],
    attr='Esri_WorldTopoMap',
    name='World Topographic Map (ESRI)',
    overlay=False,  # As an optional overlay (True) or the base layer (False)
    control=True,  # Whether the Layer will be included in LayerControls
    show=True,
).add_to(m)

# Add Google Maps
folium.raster_layers.TileLayer(
    tiles='http://{s}.google.com/vt/lyrs=m&x={x}&y={y}&z={z}',
    attr='Google',
    name='Google Maps',
    subdomains=['mt0', 'mt1', 'mt2', 'mt3'],
    overlay=False,
    control=True,
    show=False,
).add_to(m)

# Add Google Satellite
folium.raster_layers.TileLayer(
    tiles='http://{s}.google.com/vt/lyrs=s&x={x}&y={y}&z={z}',
    attr='Google',
    name='Google Satellite',
    subdomains=['mt0', 'mt1', 'mt2', 'mt3'],
    overlay=False,
    control=True,
    show=False,
).add_to(m)

# Add Google Roads layer (optional)
folium.raster_layers.TileLayer(
    tiles=tile_google['Roads'],
    attr='Google',
    name='Google Roads',
    overlay=True,
    control=True,
    show=False,
).add_to(m)

folium.LayerControl(position='bottomright', collapsed=False).add_to(m)

m

The folium map can be shown properly in jupyter notebook when using 0.18.0. However, you will have a map with some possible render issue when using 0.19.0

Hopefully, the issue is clearly illustrated.

[hansthen]

I will have a look one of these days to see what can be the issue.

[Conengmo]

Thanks @lux-orc for the reproducible example, very useful. The issue seems to be with the maxNativeZoom parameter which is set to null. This is likely caused by #2029.

Before we used a parse_options function, which discarded option values that were None. This check isn't applied in the new to_javascript filter. I'll make a PR with a possible fix.

[lux-orc]

Thanks @lux-orc for the reproducible example, very useful. The issue seems to be with the maxNativeZoom parameter which is set to null. This is likely caused by #2029.

Before we used a parse_options function, which discarded option values that were None. This check isn't applied in the new to_javascript filter. I'll make a PR with a possible fix.

Thank you for working on this @Conengmo. Looking forward to having the fix :)

[Conengmo]

Just released v0.19.1 with a fix for this issue, hopefully that solves it for you. Thanks again for the bug report!

[lux-orc]

Just released v0.19.1 with a fix for this issue, hopefully that solves it for you. Thanks again for the bug report!

I just installed Folium 0.19.1 using pip—it works! Thank you so much for your time on this quick fix!