diff --git a/lofar_station_client/file_access/README.md b/lofar_station_client/file_access/README.md
index 9f5e04b9a32ca655e7f6dd1d5917b240b6cc5c7d..07f7e42201b3deed3ac1c7274ca865403c864a25 100644
--- a/lofar_station_client/file_access/README.md
+++ b/lofar_station_client/file_access/README.md
@@ -66,14 +66,9 @@ these attributes. Therefor `attribute` allows to specify another member in the c
## Read a HDF file
-A file can be read using the `Hdf5FileReader` class:
+A file can be read using `read_hdf5`:
```python
-with read_hdf5('file_name.h5') as f:
- data = f.read(Data)
+with read_hdf5('file_name.h5', Data) as data:
+ a = data.first_attr
```
-
-It should always be used in a `with` block to make sure the HDF5 file handles are cleand up properly.
-
-Currently, the data object read from the file is only usable within the `with` block since the data is lazily loaded.
-If needed eager loading could be added in the future.
diff --git a/lofar_station_client/file_access/__init__.py b/lofar_station_client/file_access/__init__.py
index 8bdfbc149f839a0f248b83f2be9a91f745c22cce..661011d5f68854681f05fc8194dd1da01c8459e9 100644
--- a/lofar_station_client/file_access/__init__.py
+++ b/lofar_station_client/file_access/__init__.py
@@ -8,6 +8,6 @@ Contains classes to interact with (hdf5) files
from ._hdf5_attribute_def import attribute
from ._hdf5_member_def import member
-from .file_reader import Hdf5FileReader, read_hdf5
+from .hdf_file_reader import Hdf5FileReader, read_hdf5
__all__ = ["Hdf5FileReader", "attribute", "member", "read_hdf5"]
diff --git a/lofar_station_client/file_access/file_reader.py b/lofar_station_client/file_access/hdf_file_reader.py
similarity index 73%
rename from lofar_station_client/file_access/file_reader.py
rename to lofar_station_client/file_access/hdf_file_reader.py
index 1950b668131b2e98015dd07c36ebba1e7ca9faa0..a98a4ccf1aca44591594e4552a9dbaa1dcdc57f1 100644
--- a/lofar_station_client/file_access/file_reader.py
+++ b/lofar_station_client/file_access/hdf_file_reader.py
@@ -5,7 +5,7 @@
Contains classes to handle file reading
"""
-from typing import TypeVar, Type
+from typing import TypeVar, Generic
import h5py
@@ -14,21 +14,22 @@ from ._hdf5_utils import _detect_reader
T = TypeVar("T")
-class Hdf5FileReader:
+class Hdf5FileReader(Generic[T]):
"""
HDF5 specific file reader
"""
- def __init__(self, name):
+ def __init__(self, name, target_type):
self._hdf5_file = h5py.File(name, "r")
+ self._target_type = target_type
self._is_closed = False
- def read(self, target_type: Type[T]) -> T:
+ def read(self) -> T:
"""
Read the opened file into a pythonic representation specified by target_type.
Will automatically figure out if target_type is a dict or a regular object
"""
- reader = _detect_reader(target_type)
+ reader = _detect_reader(self._target_type)
return reader(self._hdf5_file)
def close(self):
@@ -40,7 +41,7 @@ class Hdf5FileReader:
del self._hdf5_file
def __enter__(self):
- return self
+ return self.read()
def __exit__(self, exc_type, exc_val, exc_tb):
self.close()
@@ -49,8 +50,8 @@ class Hdf5FileReader:
self.close()
-def read_hdf5(name: str) -> Hdf5FileReader:
+def read_hdf5(name: str, target_type: T):
"""
Open a HDF5 file by name/path
"""
- return Hdf5FileReader(name)
+ return Hdf5FileReader[T](name, target_type)
diff --git a/tests/file_access/test_file_reader.py b/tests/file_access/test_file_reader.py
index e7f5f2443cbcf61fbd6d524f8973f20632728436..c731ebacf7b716fccbee594c17c3bebbd5219186 100644
--- a/tests/file_access/test_file_reader.py
+++ b/tests/file_access/test_file_reader.py
@@ -53,9 +53,8 @@ class CalTableDict(Dict[str, Dict[str, ndarray]]):
class TestHdf5FileReader(base.TestCase):
def test_file_reading(self):
with read_hdf5(
- dirname(__file__) + "/SST_2022-11-15-14-21-39.h5"
- ) as file_reader:
- ds = file_reader.read(Dict[str, DataSet])
+ dirname(__file__) + "/SST_2022-11-15-14-21-39.h5", Dict[str, DataSet]
+ ) as ds:
self.assertEqual(21, len(ds.keys()))
item = ds["SST_2022-11-15T14:21:59.000+00:00"]
self.assertFalse(
@@ -90,8 +89,7 @@ class TestHdf5FileReader(base.TestCase):
self.assertEqual(100, len(item.sub_set.values))
def test_read_attribute(self):
- with read_hdf5(dirname(__file__) + "/cal-test.h5") as file_reader:
- ds = file_reader.read(AttrDataSet)
+ with read_hdf5(dirname(__file__) + "/cal-test.h5", AttrDataSet) as ds:
self.assertEqual("test-station", ds.observation_station)
self.assertEqual("dset_attr", ds.test_attr)
self.assertIsNone(ds.observation_station_optional)
@@ -103,16 +101,14 @@ class TestHdf5FileReader(base.TestCase):
)
def test_read_ndarray(self):
- with read_hdf5(dirname(__file__) + "/cal-test.h5") as file_reader:
- ds = file_reader.read(AttrDataSet)
+ with read_hdf5(dirname(__file__) + "/cal-test.h5", AttrDataSet) as ds:
d = ds.calibration_data
self.assertTrue(isinstance(d, ndarray))
self.assertEqual(512, d.shape[0])
self.assertEqual(96, d.shape[1])
def test_read_derived_dict(self):
- with read_hdf5(dirname(__file__) + "/cal-test-dict.h5") as file_reader:
- ds = file_reader.read(CalTable)
+ with read_hdf5(dirname(__file__) + "/cal-test-dict.h5", CalTable) as ds:
self.assertEqual(5, len(ds))
self.assertEqual("test-station", ds.observation_station)
ant_2 = ds["ant_2"]
@@ -122,8 +118,7 @@ class TestHdf5FileReader(base.TestCase):
self.assertEqual("ant_2_y", ant_2.y_attr)
def test_read_derived_double_dict(self):
- with read_hdf5(dirname(__file__) + "/cal-test-dict.h5") as file_reader:
- ds = file_reader.read(CalTableDict)
+ with read_hdf5(dirname(__file__) + "/cal-test-dict.h5", CalTableDict) as ds:
self.assertEqual(5, len(ds))
ant_2 = ds["ant_2"]
self.assertTrue("x" in ant_2)
@@ -141,9 +136,8 @@ class TestHdf5FileReader(base.TestCase):
)
with read_hdf5(
- dirname(__file__) + "/SST_2022-11-15-14-21-39.h5"
- ) as file_reader:
- ds = file_reader.read(ObjectDataSet)
+ dirname(__file__) + "/SST_2022-11-15-14-21-39.h5", ObjectDataSet
+ ) as ds:
self.assertEqual(
["nof_payload_errors", "nof_valid_payloads", "values"],
list(ds.item_1.keys()),
@@ -161,9 +155,8 @@ class TestHdf5FileReader(base.TestCase):
sub_set: List[int] = member(name="test")
with read_hdf5(
- dirname(__file__) + "/SST_2022-11-15-14-21-39.h5"
- ) as file_reader:
- ds = file_reader.read(Dict[str, BrokenDataSet])
+ dirname(__file__) + "/SST_2022-11-15-14-21-39.h5", Dict[str, BrokenDataSet]
+ ) as ds:
item = ds["SST_2022-11-15T14:21:39.000+00:00"]
with self.assertRaises(TypeError):
_ = item.nof_payload_errors
@@ -173,9 +166,7 @@ class TestHdf5FileReader(base.TestCase):
_ = item.sub_set
def test_reader_close(self):
- file_reader = read_hdf5(dirname(__file__) + "/SST_2022-11-15-14-21-39.h5")
+ file_reader = read_hdf5(
+ dirname(__file__) + "/SST_2022-11-15-14-21-39.h5", Dict[str, DataSet]
+ )
file_reader.close()
-
- with read_hdf5(dirname(__file__) + "/SST_2022-11-15-14-21-39.h5") as f:
- f.close()
- f.close()