refactor: create test tiles on top of rio RGB.tiff

rio_vrt/enums.py

@@ -2,6 +2,7 @@
 
 types = {
     "byte": "Byte",
+    "uint8": "Byte",
     "uint16": "UInt16",
     "int16": "Int16",
     "uint32": "UInt32",

rio_vrt/vrt.py

@@ -18,15 +18,19 @@ def _add_source_content(
 ) -> None:
     """Add the content of a sourcefile in xml."""
     width, height = str(src.width), str(src.height)
-    blockx, blocky = str(src.profile["blockxsize"]), str(src.profile["blockysize"])
+    blockx = str(src.profile.get("blockxsize", ""))
+    blocky = str(src.profile.get("blockysize", ""))
 
     attr = {
         "RasterXSize": width,
         "RasterYSize": height,
         "DataType": type,
-        "BlockXSize": blockx,
-        "BlockYSize": blocky,
     }
+
+    # optional attributes
+    if blockx and blocky:
+        attr["BlockXSize"], attr["BlockySize"] = blockx, blocky
+
     ET.SubElement(Source, "SourceProperties", attr)
 
     attr = {"xOff": "0", "yOff": "0", "xSize": width, "ySize": height}
@@ -162,13 +166,20 @@ def build_vrt(
                 color = colorinterps[i - 1].name.capitalize()
                 ET.SubElement(VRTRasterBands_dict[i], "ColorInterp").text = color
 
+            if nodatavals[i - 1] is not None:
+                text = str(nodatavals[i - 1])
+                ET.SubElement(VRTRasterBands_dict[i], "NoDataValue").text = text
+
         # add the files
         for f in files:
             relativeToVRT = "1" if relative is True else "0"
             with rio.open(f) as src:
                 for i in indexes:
                     is_alpha = colorinterps[i - 1] == ColorInterp.alpha
-                    source_type = "ComplexSource" if is_alpha else "SimpleSource"
+                    has_nodata = nodatavals[i - 1] is not None
+                    source_type = (
+                        "ComplexSource" if is_alpha or has_nodata else "SimpleSource"
+                    )
                     Source = ET.SubElement(VRTRasterBands_dict[i], source_type)
 
                     attr = {"relativeToVRT": relativeToVRT}
@@ -187,7 +198,7 @@ def build_vrt(
 
                     if nodatavals[i - 1] is not None:
                         text = str(nodatavals[i - 1])
-                        ET.SubElement(Source, "NoDataValue").text = text
+                        ET.SubElement(Source, "NODATA").text = text
 
                     if colorinterps[i - 1] == ColorInterp.alpha:
                         ET.SubElement(Source, "UseMaskBand").text = "true"

tests/conftest.py

@@ -1,10 +1,49 @@
 """Pytest session configuration."""
 
+from itertools import product
 from pathlib import Path
-from typing import List
+from typing import Generator, List, Tuple
 
 import pytest
+import rasterio as rio
 from natsort import natsorted
+from rasterio import transform, windows
+
+
+def get_tile_size(ds: rio.DatasetReader) -> int:
+    """Return the size tile corresponding to the giveb file.
+
+    .. warning::
+        The file must be squared.
+
+    Args:
+        ds: the rasterio dataset
+
+    Returns:
+        the square size
+    """
+    return int(ds.width / 4), int(ds.height / 4)
+
+
+def get_tiles(
+    ds: rio.DatasetReader, size: Tuple[int, int]
+) -> Generator[int, windows.Window, transform.Affine]:
+    """Return the window and transformed associated to a tile from a given dataset.
+
+    Args:
+        ds: the rasterio dataset
+        size: the tile size
+    """
+    xsize, ysize = size
+    nols, nrows = ds.width, ds.height
+    offsets = product(range(0, nols, xsize), range(0, nrows, ysize))
+    big_window = windows.Window(col_off=0, row_off=0, width=nols, height=nrows)
+    for col_off, row_off in offsets:
+        window = windows.Window(
+            col_off=col_off, row_off=row_off, width=xsize, height=ysize
+        ).intersection(big_window)
+        transform = windows.transform(window, ds.transform)
+        yield window, transform
 
 
 @pytest.fixture(scope="session")
@@ -16,5 +55,29 @@ def data_dir() -> Path:
 @pytest.fixture(scope="session")
 def tiles(data_dir: Path) -> List[Path]:
     """Returns the list of tiles from the data folder as relative path."""
-    tiles = [f for f in data_dir.glob("*.tiff")]
-    return natsorted(tiles)
+    # download the data from the rasterio repository
+    rio_data = "https://github.com/rasterio/rasterio/raw/main/tests/data/RGB.byte.tif"
+
+    # split the data in tiles in 2 resolutions
+    raw_dir = data_dir / "raw"
+    raw_dir.mkdir(exist_ok=True)
+
+    # create a list of files
+    with rio.open(rio_data) as src:
+        profile = src.profile.copy()
+        size = get_tile_size(src)
+
+        for i, tile in enumerate(get_tiles(src, size)):
+            window, affine = tile
+            profile.update(transform=affine, width=window.width, height=window.height)
+            file = raw_dir / f"tile{i}.tiff"
+            with rio.open(file, "w", **profile) as dst:
+                dst.write(src.read(window=window))
+
+    # yield the sorted list
+    tiles = [f for f in raw_dir.glob("*.tiff")]
+    yield natsorted(tiles)
+
+    # flush the folder
+    [f.unlink() for f in tiles]
+    raw_dir.rmdir()

tests/test_rio_vrt.py

@@ -26,7 +26,7 @@ def test_build_vrt_html_shema(tiles: List[Path], data_dir: Path) -> None:
     with NamedTemporaryFile(suffix=".vrt", dir=data_dir) as vrt_path:
         vrt_file = rio_vrt.build_vrt(vrt_path.name, tiles)
         xml_schema = xmlschema.XMLSchema(urlopen(_xsd_file))
-        assert xml_schema.is_valid(vrt_file)
+        assert xml_schema.validate(vrt_file) is None
 
 
 def test_build_vrt_stack_shema(tiles: List[Path], data_dir: Path) -> None:
@@ -39,7 +39,7 @@ def test_build_vrt_stack_shema(tiles: List[Path], data_dir: Path) -> None:
     with NamedTemporaryFile(suffix=".vrt", dir=data_dir) as vrt_path:
         vrt_file = rio_vrt.build_vrt(vrt_path.name, tiles, mosaic=False)
         xml_schema = xmlschema.XMLSchema(urlopen(_xsd_file))
-        assert xml_schema.is_valid(vrt_file)
+        assert xml_schema.validate(vrt_file) is None
 
 
 def test_build_vrt_complete(tiles: List[Path], data_dir: Path, file_regression) -> None: