Add support for visualizing in-memory raster

[giswqs]

Just figured out how to visualize in-memory raster dataset with localtileserver, making it possible to visualize rasterio/xarray datasets without writing files to hard drive. This is exciting!

import rasterio
from ipyleaflet import Map
from localtileserver import TileClient, get_leaflet_tile_layer

# Open a rasterio dataset
dataset = rasterio.open('https://open.gishub.org/data/raster/srtm90.tif')
data_array = dataset.read(1)

# Do some processing on the data array
data_array[data_array < 1000] = 0

# Create rasterio dataset in memory
memory_file = rasterio.MemoryFile()
raster_dataset = memory_file.open(driver='GTiff',
                                  height=data_array.shape[0],
                                  width=data_array.shape[1],
                                  count=1,
                                  dtype=str(data_array.dtype),
                                  crs=dataset.crs,
                                  transform=dataset.transform)

# Write data array values to the rasterio dataset
raster_dataset.write(data_array, 1)
raster_dataset.close()

# Read the dataset from memory
dataset_reader = rasterio.open(raster_dataset.name, mode='r')

# Create a TileClient and a Leaflet map
client = TileClient(dataset_reader)
t = get_leaflet_tile_layer(client, cmap='terrain', vmin=100, vmax=3000)
m = Map(center=client.center(), zoom=client.default_zoom)
m.add_layer(t)
m