Dmrpp migration

conftest.py

@@ -356,6 +356,15 @@ def hdf5_empty(tmp_path: Path) -> str:
     return str(filepath)
 
 
+@pytest.fixture
+def hdf5_missing_value(tmp_path: Path) -> str:
+    """Create an empty HDF5 file."""
+    filepath = tmp_path / "compact_lowlevel.h5"
+    with h5py.File(filepath, "w") as f:
+        f.create_dataset("my_dataset", shape=(10,), dtype="int64")
+    return str(filepath)
+
+
 @pytest.fixture
 def hdf5_scalar(tmp_path: Path) -> str:
     """Create an HDF5 file with a scalar dataset."""

docs/releases.md

@@ -33,6 +33,9 @@
 
 ### Internal changes
 
+- `DMRPPParser` is now migrated to [pydap](https://github.com/pydap/pydap) (`pydap>=3.5.10`) (see [pydap#417](https://github.com/pydap/pydap/issues/417)). To use the dmrpp parser one must install the extra `pip install "virtualizarr[dmrpp]"`.
+  By [Miguel Jimenez-Urias](https://github.com/Mikejmnez)
+
 - Speed up virtual chunk container validation when writing to Icechunk by passing the supported prefixes as a tuple to `str.startswith`, which runs the loop over prefixes in C rather than in a Python generator. The per-reference check is now ~2.6x faster in the common single-container case, which matters when writing manifests with millions of virtual references. The check is still a per-reference Python loop overall (see [icechunk#1167](https://github.com/earth-mover/icechunk/issues/1167) for pushing it down to Icechunk entirely).
   By [Tom Nicholas](https://github.com/TomNicholas).
 
@@ -249,6 +252,7 @@ Brings `region`-writing support in `.to_icechunk()`, a `ZarrParser` with orders
 - Fix `ZarrParser` to use public attribute instead of private one ([#916](https://github.com/zarr-developers/VirtualiZarr/pull/916)).
   By [Max Jones](https://github.com/maxrjones).
 
+
 ### Documentation
 
 - Added FAQ answer comparing the Kerchunk and Icechunk serialization formats. ([#818](https://github.com/zarr-developers/VirtualiZarr/pull/818)).

pyproject.toml

@@ -50,6 +50,11 @@ hdf = [
     "imagecodecs-numcodecs==2024.6.1",
 ]
 
+# dmrpp
+dmrpp = [
+    "pydap @ git+https://github.com/pydap/pydap.git@refs/pull/697/head",
+]
+
 zarr = ["arro3-core"]
 
 # kerchunk-based parsers
@@ -83,7 +88,8 @@ all_parsers = [
     "virtualizarr[kerchunk_parquet]",
     "virtualizarr[tiff]",
     "virtualizarr[grib]",
-    "virtualizarr[zarr]"
+    "virtualizarr[zarr]",
+    "virtualizarr[dmrpp]",
 ]
 
 # writers
@@ -214,8 +220,8 @@ run-flaky-tests = { cmd = "pytest -m flaky --run-flaky --run-network-tests --ver
 min-deps = ["dev", "test", "hdf", "hdf5-lib"] # VirtualiZarr/conftest.py using h5py, so the minimum set of dependencies for testing still includes hdf libs
 # Inherit from min-deps to get all the test commands, along with optional dependencies
 test = ["dev", "test", "remote", "hdf", "netcdf3", "fits", "icechunk", "kerchunk", "kerchunk_parquet", "hdf5-lib", "zarr", "py314"]
-test-py312 = ["dev", "test", "remote", "hdf", "netcdf3", "fits", "icechunk", "kerchunk", "kerchunk_parquet", "hdf5-lib", "tiff", "grib", "zarr", "py312"] # test against python 3.13
-test-py313 = ["dev", "test", "remote", "hdf", "netcdf3", "fits", "icechunk", "kerchunk", "kerchunk_parquet", "hdf5-lib", "tiff", "grib", "zarr", "py313"] # test against python 3.13
+test-py312 = ["dev", "test", "remote", "hdf", "netcdf3", "fits", "icechunk", "kerchunk", "kerchunk_parquet", "hdf5-lib", "tiff", "grib", "dmrpp", "zarr", "py312"] # test against python 3.13
+test-py313 = ["dev", "test", "remote", "hdf", "netcdf3", "fits", "icechunk", "kerchunk", "kerchunk_parquet", "hdf5-lib", "tiff", "grib", "dmrpp", "zarr", "py313"] # test against python 3.13
 test-py314 = ["dev", "test", "remote", "hdf", "netcdf3", "fits", "icechunk", "kerchunk", "kerchunk_parquet", "hdf5-lib", "zarr", "py314"] # test against python 3.14
 minio = ["dev", "remote", "hdf", "netcdf3", "fits", "icechunk", "kerchunk", "hdf5-lib", "py314", "zarr", "minio"]
 # tiff (virtual-tiff) is excluded: virtual-tiff 0.5.0 imports zarr's CodecJSON
@@ -267,6 +273,7 @@ module = [
     "ujson",
     "zarr",
     "requests",
+    "pydap.*",
 ]
 ignore_missing_imports = true