load files into memory for processing fist

sed/loader/mpes/loader.py

@@ -5,6 +5,7 @@
 """
 import datetime
 import glob
+import io
 import json
 import os
 from typing import Dict
@@ -27,6 +28,29 @@
 from sed.loader.base.loader import BaseLoader
 
 
+def load_h5_in_memory(file_path):
+    """
+    Load an HDF5 file entirely into memory and open it with h5py.
+
+    Parameters:
+        file_path (str): Path to the .h5 file.
+
+    Returns:
+        h5py.File: An h5py File object representing the in-memory HDF5 file.
+    """
+    # Read the entire file into memory
+    with open(file_path, "rb") as f:
+        file_content = f.read()
+
+    # Load the content into a BytesIO object
+    file_buffer = io.BytesIO(file_content)
+
+    # Open the HDF5 file using h5py from the in-memory buffer
+    h5_file = h5py.File(file_buffer, "r")
+
+    return h5_file
+
+
 def hdf5_to_dataframe(
     files: Sequence[str],
     group_names: Sequence[str] = None,
@@ -67,20 +91,22 @@ def hdf5_to_dataframe(
 
     # Read a file to parse the file structure
     test_fid = kwds.pop("test_fid", 0)
-    test_proc = h5py.File(files[test_fid])
+    test_proc = load_h5_in_memory(files[test_fid])
     if group_names == []:
         group_names, alias_dict = get_groups_and_aliases(
             h5file=test_proc,
             search_pattern="Stream",
         )
 
+    test_proc.close()
+
     column_names = [alias_dict.get(group, group) for group in group_names]
 
     if time_stamps:
         column_names.append(time_stamp_alias)
 
     test_array = hdf5_to_array(
-        h5file=test_proc,
+        h5filename=files[test_fid],
         group_names=group_names,
         time_stamps=time_stamps,
         ms_markers_group=ms_markers_group,
@@ -94,7 +120,7 @@ def hdf5_to_dataframe(
             arrays.append(
                 da.from_delayed(
                     dask.delayed(hdf5_to_array)(
-                        h5file=h5py.File(f),
+                        h5filename=f,
                         group_names=group_names,
                         time_stamps=time_stamps,
                         ms_markers_group=ms_markers_group,
@@ -155,20 +181,22 @@ def hdf5_to_timed_dataframe(
 
     # Read a file to parse the file structure
     test_fid = kwds.pop("test_fid", 0)
-    test_proc = h5py.File(files[test_fid])
+    test_proc = load_h5_in_memory(files[test_fid])
     if group_names == []:
         group_names, alias_dict = get_groups_and_aliases(
             h5file=test_proc,
             search_pattern="Stream",
         )
 
+    test_proc.close()
+
     column_names = [alias_dict.get(group, group) for group in group_names]
 
     if time_stamps:
         column_names.append(time_stamp_alias)
 
     test_array = hdf5_to_timed_array(
-        h5file=test_proc,
+        h5filename=files[test_fid],
         group_names=group_names,
         time_stamps=time_stamps,
         ms_markers_group=ms_markers_group,
@@ -182,7 +210,7 @@ def hdf5_to_timed_dataframe(
             arrays.append(
                 da.from_delayed(
                     dask.delayed(hdf5_to_timed_array)(
-                        h5file=h5py.File(f),
+                        h5filename=f,
                         group_names=group_names,
                         time_stamps=time_stamps,
                         ms_markers_group=ms_markers_group,
@@ -237,7 +265,7 @@ def get_groups_and_aliases(
 
 
 def hdf5_to_array(
-    h5file: h5py.File,
+    h5filename: str,
     group_names: Sequence[str],
     data_type: str = "float32",
     time_stamps=False,
@@ -248,14 +276,10 @@ def hdf5_to_array(
     2-dimensional array with the corresponding values.
 
     Args:
-        h5file (h5py.File):
-            hdf5 file handle to read from
-        group_names (str):
-            group names to read
-        data_type (str, optional):
-            Data type of the output data. Defaults to "float32".
-        time_stamps (bool, optional):
-            Option to calculate time stamps. Defaults to False.
+        h5filename (str): hdf5 file name to read from
+        group_names (str): group names to read
+        data_type (str, optional): Data type of the output data. Defaults to "float32".
+        time_stamps (bool, optional): Option to calculate time stamps. Defaults to False.
         ms_markers_group (str): h5 column containing timestamp information.
             Defaults to "msMarkers".
         first_event_time_stamp_key (str): h5 attribute containing the start
@@ -267,6 +291,8 @@ def hdf5_to_array(
 
     # Delayed array for loading an HDF5 file of reasonable size (e.g. < 1GB)
 
+    h5file = load_h5_in_memory(h5filename)
+
     # Read out groups:
     data_list = []
     for group in group_names:
@@ -316,11 +342,13 @@ def hdf5_to_array(
 
         data_list.append(time_stamp_data)
 
+    h5file.close()
+
     return np.asarray(data_list)
 
 
 def hdf5_to_timed_array(
-    h5file: h5py.File,
+    h5filename: str,
     group_names: Sequence[str],
     data_type: str = "float32",
     time_stamps=False,
@@ -331,14 +359,10 @@ def hdf5_to_timed_array(
     timed version of a 2-dimensional array with the corresponding values.
 
     Args:
-        h5file (h5py.File):
-            hdf5 file handle to read from
-        group_names (str):
-            group names to read
-        data_type (str, optional):
-            Data type of the output data. Defaults to "float32".
-        time_stamps (bool, optional):
-            Option to calculate time stamps. Defaults to False.
+        h5filename (str): hdf5 file name to read from
+        group_names (str): group names to read
+        data_type (str, optional): Data type of the output data. Defaults to "float32".
+        time_stamps (bool, optional): Option to calculate time stamps. Defaults to False.
         ms_markers_group (str): h5 column containing timestamp information.
             Defaults to "msMarkers".
         first_event_time_stamp_key (str): h5 attribute containing the start
@@ -351,6 +375,8 @@ def hdf5_to_timed_array(
 
     # Delayed array for loading an HDF5 file of reasonable size (e.g. < 1GB)
 
+    h5file = load_h5_in_memory(h5filename)
+
     # Read out groups:
     data_list = []
     ms_marker = np.asarray(h5file[ms_markers_group])
@@ -386,6 +412,8 @@ def hdf5_to_timed_array(
 
         data_list.append(time_stamp_data)
 
+    h5file.close()
+
     return np.asarray(data_list)
 
 
@@ -692,14 +720,14 @@ def get_start_and_end_time(self) -> Tuple[float, float]:
         Returns:
             Tuple[float, float]: A tuple containing the start and end time stamps
         """
-        h5file = h5py.File(self.files[0])
+        h5file = load_h5_in_memory(self.files[0])
         timestamps = hdf5_to_array(
             h5file,
             group_names=self._config["dataframe"]["hdf5_groupnames"],
             time_stamps=True,
         )
         ts_from = timestamps[-1][1]
-        h5file = h5py.File(self.files[-1])
+        h5file = load_h5_in_memory(self.files[-1])
         timestamps = hdf5_to_array(
             h5file,
             group_names=self._config["dataframe"]["hdf5_groupnames"],
@@ -929,7 +957,7 @@ def get_count_rate(
         for fid in fids:
             try:
                 count_rate_, secs_ = get_count_rate(
-                    h5py.File(self.files[fid]),
+                    load_h5_in_memory(self.files[fid]),
                     ms_markers_group=ms_markers_group,
                 )
                 secs_list.append((accumulated_time + secs_).T)
@@ -974,7 +1002,7 @@ def get_elapsed_time(self, fids: Sequence[int] = None, **kwds) -> float:
         for fid in fids:
             try:
                 secs += get_elapsed_time(
-                    h5py.File(self.files[fid]),
+                    load_h5_in_memory(self.files[fid]),
                     ms_markers_group=ms_markers_group,
                 )
             except OSError as exc: