draw_small_map_with_rasterio.py

import random

import numpy as np
import rasterio


def draw_map():
    x_size_raster = 500
    y_size_raster = 300
    raster_map = np.ones((x_size_raster, y_size_raster), np.uint8)  # be careful with numpy array types, not all are supported!
    for shape_record in range(200):
        row = random.randint(0, x_size_raster - 1)
        col = random.randint(0, y_size_raster - 1)
        raster_map[row, col] = random.randint(-10, 40)
    return raster_map


def save_map(path, raster_map):
    new_dataset = rasterio.open(path, 'w', driver='GTiff',
        height=raster_map.shape[0], width=raster_map.shape[1], count=1,
        dtype=raster_map.dtype, crs='EPSG:4326')
    new_dataset.write(raster_map, 1)
    new_dataset.close()


def demo():
    m1 = draw_map()
    save_map("m1.tif", m1)

demo()

Used to report irritating error message in rasterio/rasterio#1007.
np.int8 is not supported but e.g. np.uint8