Fix remote dask orientation handling for GeoTIFF reads

xrspatial/geotiff/__init__.py

@@ -2186,6 +2186,13 @@ def read_geotiff_dask(source: str, *,
         finally:
             _src.close()
         http_meta = (http_header, http_ifd)
+        if http_ifd.orientation != 1:
+            raise ValueError(
+                f"Orientation tag (274) is {http_ifd.orientation}; "
+                f"dask-chunked reads (chunks=...) are not supported for "
+                f"non-default orientation on remote GeoTIFF sources. Read "
+                f"the full array first, then slice/chunk it."
+            )
         # Wrap the parsed metadata in a single dask Delayed so every
         # window task takes it as a graph input, not a Python closure.
         # Without this, the (TIFFHeader, IFD) pair -- which can carry

xrspatial/geotiff/tests/test_http_dask_orientation_1794.py

@@ -0,0 +1,81 @@
+"""Remote dask reads must not bypass TIFF Orientation handling (#1794)."""
+from __future__ import annotations
+
+import http.server
+import socketserver
+import threading
+
+import numpy as np
+import pytest
+
+from xrspatial.geotiff import open_geotiff
+
+tifffile = pytest.importorskip("tifffile")
+
+
+def _write_with_orientation(path, arr, orientation):
+    tifffile.imwrite(
+        str(path),
+        arr,
+        extratags=[(274, 'H', 1, orientation, True)],
+    )
+
+
+class _RangeHandler(http.server.BaseHTTPRequestHandler):
+    payload: bytes = b''
+
+    def do_GET(self):  # noqa: N802
+        rng = self.headers.get('Range')
+        if rng and rng.startswith('bytes='):
+            spec = rng[len('bytes='):]
+            start_s, _, end_s = spec.partition('-')
+            start = int(start_s)
+            end = int(end_s) if end_s else len(self.payload) - 1
+            chunk = self.payload[start:end + 1]
+            self.send_response(206)
+            self.send_header('Content-Type', 'application/octet-stream')
+            self.send_header(
+                'Content-Range',
+                f'bytes {start}-{start + len(chunk) - 1}/{len(self.payload)}',
+            )
+            self.send_header('Content-Length', str(len(chunk)))
+            self.end_headers()
+            self.wfile.write(chunk)
+            return
+        self.send_response(200)
+        self.send_header('Content-Type', 'application/octet-stream')
+        self.send_header('Content-Length', str(len(self.payload)))
+        self.end_headers()
+        self.wfile.write(self.payload)
+
+    def log_message(self, *_args, **_kwargs):
+        pass
+
+
+def _serve(payload: bytes):
+    handler_cls = type(
+        'RangeHandler1794', (_RangeHandler,), {'payload': payload}
+    )
+    httpd = socketserver.TCPServer(('127.0.0.1', 0), handler_cls)
+    port = httpd.server_address[1]
+    thread = threading.Thread(target=httpd.serve_forever, daemon=True)
+    thread.start()
+    return httpd, port
+
+
+def test_http_dask_read_rejects_non_default_orientation(tmp_path, monkeypatch):
+    monkeypatch.setenv('XRSPATIAL_GEOTIFF_ALLOW_PRIVATE_HOSTS', '1')
+    arr = np.arange(64, dtype=np.uint8).reshape(8, 8)
+    path = tmp_path / "tmp_1794_orientation_2.tif"
+    _write_with_orientation(path, arr, 2)
+
+    payload = path.read_bytes()
+    httpd, port = _serve(payload)
+    try:
+        url = f'http://127.0.0.1:{port}/tmp_1794_orientation_2.tif'
+        with pytest.raises(ValueError, match="Orientation tag"):
+            open_geotiff(url, chunks=4)
+    finally:
+        httpd.shutdown()
+        httpd.server_close()
+