Hdf with

pandas/io/pytables.py

@@ -13,6 +13,7 @@
 from pandas.core.common import adjoin
 import pandas.core.common as com
 import pandas._tseries as lib
+from contextlib import contextmanager
 
 # reading and writing the full object in one go
 _TYPE_MAP = {
@@ -55,6 +56,52 @@ def _tables():
         _table_mod = tables
     return _table_mod
 
+@contextmanager
+def get_store(path, mode='a', complevel=None, complib=None,
+              fletcher32=False):
+    """
+    Creates an HDFStore instance. This function can be used in a with statement
+
+    Parameters
+    ----------
+    path : string
+        File path to HDF5 file
+    mode : {'a', 'w', 'r', 'r+'}, default 'a'
+
+        ``'r'``
+            Read-only; no data can be modified.
+        ``'w'``
+            Write; a new file is created (an existing file with the same
+            name would be deleted).
+        ``'a'``
+            Append; an existing file is opened for reading and writing,
+            and if the file does not exist it is created.
+        ``'r+'``
+            It is similar to ``'a'``, but the file must already exist.
+    complevel : int, 1-9, default 0
+            If a complib is specified compression will be applied
+            where possible
+    complib : {'zlib', 'bzip2', 'lzo', 'blosc', None}, default None
+            If complevel is > 0 apply compression to objects written
+            in the store wherever possible
+    fletcher32 : bool, default False
+            If applying compression use the fletcher32 checksum
+
+    Examples
+    --------
+    >>> with get_store('test.h5') as store:
+    >>>     store['foo'] = bar   # write to HDF5
+    >>>     bar = store['foo']   # retrieve
+    """
+    store = None
+    try:
+        store = HDFStore(path, mode=mode, complevel=complevel,
+                         complib=complib, fletcher32=False)
+        yield store
+    finally:
+        if store is not None:
+            store.close()
+
 class HDFStore(object):
     """
     dict-like IO interface for storing pandas objects in PyTables

pandas/io/tests/test_pytables.py

@@ -7,7 +7,7 @@
 import numpy as np
 
 from pandas import Series, DataFrame, Panel, DateRange, MultiIndex
-from pandas.io.pytables import HDFStore
+from pandas.io.pytables import HDFStore, get_store
 import pandas.util.testing as tm
 
 try:
@@ -31,6 +31,22 @@ def tearDown(self):
         self.store.close()
         os.remove(self.path)
 
+    def test_factory_fun(self):
+        try:
+            with get_store(self.scratchpath) as tbl:
+                raise ValueError('blah')
+        except ValueError:
+            pass
+
+        with get_store(self.scratchpath) as tbl:
+            tbl['a'] = tm.makeDataFrame()
+
+        with get_store(self.scratchpath) as tbl:
+            self.assertEquals(len(tbl), 1)
+            self.assertEquals(type(tbl['a']), DataFrame)
+
+        os.remove(self.scratchpath)
+
     def test_len_keys(self):
         self.store['a'] = tm.makeTimeSeries()
         self.store['b'] = tm.makeStringSeries()
@@ -473,6 +489,8 @@ def test_store_datetime_fractional_secs(self):
         self.store['a'] = series
         self.assertEquals(self.store['a'].index[0], dt)
 
+
+
 def curpath():
     pth, _ = os.path.split(os.path.abspath(__file__))
     return pth