tests: implement pytest tests for disk and sqlite cache backends

.github/workflows/build-linux.yml

@@ -26,13 +26,17 @@ jobs:
             if [[ 'default,maximal' =~ ${{ matrix.option }} ]]
             then
               sudo apt-get install -y libgdal-dev libfcgi-dev libpixman-1-dev
-              sudo apt-get install -y gdal-bin libxml2-utils
+              sudo apt-get install -y gdal-bin libxml2-utils python3-pip python3-gdal python3-pytest
             fi
             if [[ 'maximal' =~ ${{ matrix.option }} ]]
             then
               sudo apt-get install -y libhiredis-dev libdb-dev libmapserver-dev libpcre2-dev
             fi
 
+        - name: Install python dependencies
+          run: |
+            pip install -r ${{ github.workspace }}/tests/mcpython/requirements.txt
+
         - name: Build MapCache
           run: |
             if [[ 'minimal' == ${{ matrix.option }} ]]
@@ -80,3 +84,13 @@ jobs:
             else
               echo No test performed on this target
             fi
+
+        - name: Run python tests
+          run: |
+            if [[ 'ubuntu-latest' == ${{ matrix.os }} ]] \
+               && [[ 'default' == ${{ matrix.option }} ]]
+            then
+              pytest ${{ github.workspace }}/tests/mcpython/
+            else
+              echo No python test performed on this target
+            fi

.gitignore

@@ -3,3 +3,4 @@ nbproject/
 /build/
 /build_vagrant/
 /.vagrant/
+__pycache__

tests/data/mapcache_backend_template.xml

@@ -0,0 +1,72 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<mapcache>
+    <source name="synthetic-source" type="gdal">
+        <resample>NEAREST</resample>
+        <data>SYNTHETIC_GEOTIFF_PATH_PLACEHOLDER</data>
+    </source>
+    <grid name="synthetic_grid">
+        <extent>-500000 -500000 500000 500000</extent>
+        <srs>EPSG:3857</srs>
+        <units>m</units>
+        <origin>top-left</origin>
+        <size>256 256</size>
+        <resolutions>
+           1000
+           500
+           250
+           125
+           62.5
+           31.25
+           15.625
+           7.8125
+           3.90625
+           1.953125
+           0.9765625
+           0.48828125
+           0.244140625
+           0.1220703125
+           0.06103515625
+           0.030517578125
+           0.0152587890625
+           0.00762939453125
+        </resolutions>
+    </grid>
+    <cache name="disk" type="disk">
+        <base>TILE_CACHE_BASE_DIR/disk</base>
+    </cache>
+    <tileset name="disk-tileset">
+        <cache>disk</cache>
+        <source>synthetic-source</source>
+        <grid>synthetic_grid</grid>
+        <format>PNG</format> <!-- Using PNG for lossless data for correctness tests -->
+        <resample>NEAREST</resample>
+        <metatile>1 1</metatile>
+    </tileset>
+    <!-- Required utils have not landed yet
+    <cache name="lmdb" type="lmdb">
+        <base>TILE_CACHE_BASE_DIR/lmdb</base>
+    </cache>
+    <tileset name="lmdb-tileset">
+        <cache>lmdb</cache>
+        <source>synthetic-source</source>
+        <grid>synthetic_grid</grid>
+        <format>PNG</format>
+        <resample>NEAREST</resample>
+        <metatile>1 1</metatile>
+    </tileset>
+    -->
+    <cache name="sqlite" type="sqlite3">
+        <dbfile>TILE_CACHE_BASE_DIR/cache.sqlite</dbfile>
+    </cache>
+    <tileset name="sqlite-tileset">
+        <cache>sqlite</cache>
+        <source>synthetic-source</source>
+        <grid>synthetic_grid</grid>
+        <format>PNG</format>
+        <resample>NEAREST</resample>
+        <metatile>1 1</metatile>
+    </tileset>
+    <service type="wmts" enabled="true"/>
+    <service type="wms" enabled="true"/>
+    <log_level>debug</log_level>
+</mapcache>

tests/mcpython/generate_synthetic_geotiff.py

@@ -0,0 +1,98 @@
+# Project:  MapCache
+# Purpose:  Generates a GeoTIFF with a predictable content to serve as a reference
+# Author:   Maris Nartiss
+#
+# *****************************************************************************
+# Copyright (c) 2025 Regents of the University of Minnesota.
+#
+# Permission is hereby granted, free of charge, to any person obtaining a
+# copy of this software and associated documentation files (the "Software"),
+# to deal in the Software without restriction, including without limitation
+# the rights to use, copy, modify, merge, publish, distribute, sublicense,
+# and/or sell copies of the Software, and to permit persons to whom the
+# Software is furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies of this Software or works derived from this Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+# OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+# THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+# FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+# DEALINGS IN THE SOFTWARE.
+# ****************************************************************************/
+
+import numpy as np
+import logging
+
+from osgeo import gdal, osr
+
+
+def generate_synthetic_geotiff(
+    output_filename="synthetic_test_data.tif", width=256, height=256
+):
+    """
+    Generates a synthetic GeoTIFF with unique pixel values based on their coordinates.
+    Each pixel value encodes its row and column index, allowing for detection of
+    shift and rotation errors.
+    """
+    osr.DontUseExceptions()
+    # Define image properties
+    wm_min_x = -500000
+    wm_max_x = 500000
+    wm_min_y = -500000
+    wm_max_y = 500000
+
+    pixel_width = (wm_max_x - wm_min_x) / width
+    pixel_height = (wm_min_y - wm_max_y) / height  # Negative for north-up image
+
+    # GeoTransform: [top-left x, pixel width, 0, top-left y, 0, pixel height]
+    # Top-left corner is (wm_min_x, wm_max_y)
+    geotransform = [wm_min_x, pixel_width, 0, wm_max_y, 0, pixel_height]
+
+    # Spatial Reference System (Web Mercator)
+    srs = osr.SpatialReference()
+    srs.ImportFromEPSG(3857)
+
+    # Determine appropriate data type based on image dimensions
+    # For 3-band output, we'll use uint8 for each band.
+    gdal_datatype = gdal.GDT_Byte
+    numpy_datatype = np.uint8
+    num_bands = 3
+
+    # Create the GeoTIFF file
+    driver = gdal.GetDriverByName("GTiff")
+    dataset = driver.Create(output_filename, width, height, num_bands, gdal_datatype)
+
+    if dataset is None:
+        logging.error(f"Error: Could not create {output_filename}")
+        return
+
+    dataset.SetGeoTransform(geotransform)
+    dataset.SetSpatialRef(srs)
+
+    # Create NumPy arrays to hold the pixel data for each band
+    data_band1 = np.zeros((height, width), dtype=numpy_datatype)
+    data_band2 = np.zeros((height, width), dtype=numpy_datatype)
+    data_band3 = np.zeros((height, width), dtype=numpy_datatype)
+
+    # Generate unique pixel values based on row and column index for each band
+    # Band 1 (Red): row % 256
+    # Band 2 (Green): col % 256
+    # Band 3 (Blue): (row + col) % 256
+    for row in range(height):
+        for col in range(width):
+            data_band1[row, col] = row % 256
+            data_band2[row, col] = col % 256
+            data_band3[row, col] = (row + col) % 256
+
+    # Write the data to each band
+    dataset.GetRasterBand(1).WriteArray(data_band1)
+    dataset.GetRasterBand(2).WriteArray(data_band2)
+    dataset.GetRasterBand(3).WriteArray(data_band3)
+
+    # Close the dataset
+    dataset = None
+    logging.info(f"Successfully created synthetic GeoTIFF: {output_filename}")

tests/mcpython/requirements.txt

@@ -0,0 +1,2 @@
+numpy
+pytest

tests/mcpython/test_disk_cache.py

@@ -0,0 +1,182 @@
+# Project:  MapCache
+# Purpose:  Test MapCache disk based storage backend
+# Author:   Maris Nartiss
+#
+# *****************************************************************************
+# Copyright (c) 2025 Regents of the University of Minnesota.
+#
+# Permission is hereby granted, free of charge, to any person obtaining a
+# copy of this software and associated documentation files (the "Software"),
+# to deal in the Software without restriction, including without limitation
+# the rights to use, copy, modify, merge, publish, distribute, sublicense,
+# and/or sell copies of the Software, and to permit persons to whom the
+# Software is furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies of this Software or works derived from this Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+# OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+# THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+# FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+# DEALINGS IN THE SOFTWARE.
+# ****************************************************************************/
+
+import os
+import pytest
+import numpy as np
+import logging
+
+from osgeo import gdal
+
+# Import the GeoTIFF generation function
+from generate_synthetic_geotiff import generate_synthetic_geotiff
+
+# Import generic verification functions and constants
+from verification_core import (
+    TILE_SIZE,
+    TILE_CACHE_BASE_DIR,
+    TEMP_MAPCACHE_CONFIG_DIR,
+    calculate_expected_tile_data,
+    compare_tile_arrays,
+    cleanup,
+    run_seeder,
+    create_temp_mapcache_config,
+)
+
+# --- Configuration --- #
+SYNTHETIC_GEOTIFF_FILENAME = os.path.join(
+    TEMP_MAPCACHE_CONFIG_DIR, "synthetic_test_data.tif"
+)
+GEOTIFF_WIDTH = 512
+GEOTIFF_HEIGHT = 512
+MAPCACHE_TEMPLATE_CONFIG = os.path.join(
+    os.path.dirname(__file__), "..", "data", "mapcache_backend_template.xml"
+)
+
+# --- Grid Parameters --- #
+INITIAL_RESOLUTION = 1000
+ORIGIN_X = -500000
+ORIGIN_Y = 500000
+
+
+def read_tile(tile_path, tile_size=TILE_SIZE):
+    if not os.path.exists(tile_path):
+        logging.error(f"Error: Actual tile not found at {tile_path}")
+        return None
+
+    actual_ds = gdal.Open(tile_path, gdal.GA_ReadOnly)
+    if actual_ds is None:
+        logging.error(f"Error: Could not open actual tile {tile_path}")
+        return None
+
+    # Read all bands from the actual tile
+    actual_tile_data = np.zeros(
+        (tile_size, tile_size, actual_ds.RasterCount), dtype=np.uint8
+    )
+    for i in range(actual_ds.RasterCount):
+        actual_tile_data[:, :, i] = actual_ds.GetRasterBand(i + 1).ReadAsArray()
+
+    actual_ds = None  # Close the dataset
+
+    # Mapcache might output 4 bands (RGBA) even if source is 3 bands. Handle this.
+    # If actual_tile_data has 4 bands, ignore the alpha band for comparison.
+    if actual_tile_data.shape[2] == 4:
+        actual_tile_data_rgb = actual_tile_data[:, :, :3]  # Take only RGB bands
+    elif actual_tile_data.shape[2] == 3:
+        actual_tile_data_rgb = actual_tile_data
+    else:
+        logging.error(
+            f"Error: Unexpected number of bands in actual tile: {actual_tile_data.shape[2]}"
+        )
+        return None
+
+    return actual_tile_data_rgb
+
+
+def run_mapcache_test(zoom, x, y, geotiff_path, initial_resolution, origin_x, origin_y):
+    logging.info(f"Running MapCache test for tile Z{zoom}-X{x}-Y{y}...")
+
+    # Calculate expected tile data using generic function
+    expected_tile_data = calculate_expected_tile_data(
+        zoom,
+        x,
+        y,
+        geotiff_path,
+        initial_resolution,
+        origin_x,
+        origin_y,
+    )
+    if expected_tile_data is None:
+        return False
+
+    # --- Read Actual Tile Data ---
+    actual_tile_path = os.path.join(
+        TILE_CACHE_BASE_DIR,
+        "disk",
+        "disk-tileset",
+        "synthetic_grid",
+        f"{zoom:02d}",
+        f"{x // 1000000:03d}",
+        f"{(x // 1000) % 1000:03d}",
+        f"{x % 1000:03d}",
+        f"{y // 1000000:03d}",
+        f"{(y // 1000) % 1000:03d}",
+        f"{y % 1000:03d}.png",
+    )
+
+    logging.info(f"Reading tile {actual_tile_path}")
+    actual_tile_data_rgb = read_tile(actual_tile_path, TILE_SIZE)
+    if actual_tile_data_rgb is None:
+        return False
+
+    # --- Compare ---
+    return compare_tile_arrays(expected_tile_data, actual_tile_data_rgb, zoom, x, y)
+
+
+@pytest.fixture(scope="module")
+def setup_test_environment(request):
+    cleanup()
+    logging.info("Testing disk storage backend...")
+    os.makedirs(TEMP_MAPCACHE_CONFIG_DIR, exist_ok=True)
+    generate_synthetic_geotiff(
+        output_filename=SYNTHETIC_GEOTIFF_FILENAME,
+        width=GEOTIFF_WIDTH,
+        height=GEOTIFF_HEIGHT,
+    )
+    create_temp_mapcache_config(
+        SYNTHETIC_GEOTIFF_FILENAME,
+        MAPCACHE_TEMPLATE_CONFIG,
+    )
+    run_seeder("disk-tileset", "0,1")
+
+    def teardown():
+        cleanup()
+        logging.info("Cleanup complete.")
+
+    request.addfinalizer(teardown)
+
+
+def test_disk_tiles(setup_test_environment):
+    ok0 = run_mapcache_test(
+        0,
+        0,
+        0,
+        SYNTHETIC_GEOTIFF_FILENAME,
+        INITIAL_RESOLUTION,
+        ORIGIN_X,
+        ORIGIN_Y,
+    )
+    ok1 = run_mapcache_test(
+        1,
+        1,
+        2,
+        SYNTHETIC_GEOTIFF_FILENAME,
+        INITIAL_RESOLUTION,
+        ORIGIN_X,
+        ORIGIN_Y,
+    )
+    assert ok0
+    assert ok1