geotiff: support fsspec URIs in read_geotiff_dask (#1749)

xrspatial/geotiff/__init__.py

@@ -460,7 +460,7 @@ def _read_geo_info(source, *, overview_level: int | None = None):
     from ._dtypes import resolve_bits_per_sample, tiff_dtype_to_numpy
     from ._geotags import extract_geo_info_with_overview_inheritance
     from ._header import parse_all_ifds, parse_header, select_overview_ifd
-    from ._reader import _coerce_path, _is_file_like
+    from ._reader import _CloudSource, _coerce_path, _is_file_like, _is_fsspec_uri
 
     source = _coerce_path(source)
     if _is_file_like(source):
@@ -477,6 +477,17 @@ def _read_geo_info(source, *, overview_level: int | None = None):
         except (OSError, AttributeError):
             pass
         close_data = False
+    elif isinstance(source, str) and _is_fsspec_uri(source):
+        # fsspec URI (s3://, gs://, az://, memory://, ...): pull the
+        # whole file via _CloudSource for metadata parsing. Per-chunk
+        # pixel reads in the dask graph go through _read_to_array
+        # which opens its own _CloudSource, so this fetch is metadata-only.
+        _src = _CloudSource(source)
+        try:
+            data = _src.read_all()
+        finally:
+            _src.close()
+        close_data = False
     elif isinstance(source, str):
         with open(source, 'rb') as f:
             import mmap

xrspatial/geotiff/tests/test_features.py

@@ -1051,6 +1051,39 @@ def test_memory_filesystem_full_roundtrip(self, tmp_path):
 
         fs.rm('/roundtrip.tif')
 
+    def test_dask_path_fsspec_uri_1749(self, tmp_path):
+        """read_geotiff_dask supports fsspec URIs (issue #1749).
+
+        The eager path already routed through _CloudSource via
+        _read_to_array. The dask path's _read_geo_info used plain
+        open(), which failed on memory://, s3://, etc.
+        """
+        pytest.importorskip('fsspec')
+        import fsspec
+
+        arr = np.arange(64, dtype=np.float32).reshape(8, 8)
+
+        local_path = str(tmp_path / 'src.tif')
+        to_geotiff(arr, local_path, compression='none')
+        with open(local_path, 'rb') as f:
+            tiff_bytes = f.read()
+
+        fs = fsspec.filesystem('memory')
+        fs.pipe('/dask_1749.tif', tiff_bytes)
+
+        try:
+            eager = open_geotiff('memory:///dask_1749.tif')
+            lazy = open_geotiff('memory:///dask_1749.tif', chunks=4)
+
+            # Lazy path is dask-backed
+            import dask.array as da
+            assert isinstance(lazy.data, da.Array)
+
+            np.testing.assert_array_equal(lazy.values, eager.values)
+            np.testing.assert_array_equal(lazy.values, arr)
+        finally:
+            fs.rm('/dask_1749.tif')
+
     def test_writer_cloud_scheme_detection(self):
         """Writer detects cloud schemes."""
         from xrspatial.geotiff._writer import _is_fsspec_uri