def test_versioned_item_metadata_dict():
item = VersionedItem(symbol="test",
library="test_lib",
data=None,
version=1.2,
metadata=None)
assert(item.metadata_dict() == {'symbol': 'test', 'library': 'test_lib', 'version': 1.2})
def test_versioned_item_metadata_dict():
item = VersionedItem(symbol="test",
library="test_lib",
data=None,
version=1.2,
metadata=None,
host=None)
assert(item.metadata_dict() == {'symbol': 'test', 'library': 'test_lib', 'version': 1.2})
def test_versioned_item_default_host():
item = VersionedItem(symbol="sym",
library="ONEMINUTE",
data=[1, 2, 3],
version=1.0,
metadata={'metadata': 'foo'})
expected_item = VersionedItem(symbol="sym",
library="ONEMINUTE",
data=[1, 2, 3],
version=1.0,
host=None,
metadata={'metadata': 'foo'})
assert item == expected_item
def read_metadata(self, symbol, as_of=None, allow_secondary=None):
"""
Return the metadata saved for a symbol. This method is fast as it doesn't
actually load the data.
Parameters
----------
symbol : `str`
symbol name for the item
as_of : `str` or int or `datetime.datetime`
Return the data as it was as_of the point in time.
`int` : specific version number
`str` : snapshot name which contains the version
`datetime.datetime` : the version of the data that existed as_of the requested point in time
allow_secondary : `bool` or `None`
Override the default behavior for allowing reads from secondary members of a cluster:
`None` : use the settings from the top-level `Arctic` object used to query this version store.
`True` : allow reads from secondary members
`False` : only allow reads from primary members
"""
_version = self._backing_store.read_version(self.library_name, symbol,
as_of)
return VersionedItem(symbol=symbol,
library=self.library_name,
version=_version['version'],
metadata=_version.pop('metadata', None),
data=None)
def write(self,
symbol,
data,
metadata=None,
prune_previous_version=True,
**kwargs):
"""
Write 'data' under the specified 'symbol' name to this library.
Parameters
----------
symbol : `str`
symbol name for the item
data :
to be persisted
metadata : `dict`
an optional dictionary of metadata to persist along with the symbol.
Default: None
prune_previous_version : `bool`
Removes previous (non-snapshotted) versions from the database.
Default: True
kwargs :
passed through to the write handler
Returns
-------
VersionedItem named tuple containing the metadata and version number
of the written symbol in the store.
"""
_id = bson.ObjectId()
version = {
'_id': _id,
'symbol': symbol,
'metadata': metadata,
'version': _id
}
previous_version = self._backing_store.read_version(
self.library_name, symbol)
handler = self._write_handler(version, symbol, data, **kwargs)
handler.write(self._backing_store, self.library_name, version, symbol,
data, previous_version, **kwargs)
#if prune_previous_version and previous_version:
# self._prune_previous_versions(symbol)
# self._publish_change(symbol, version)
# Insert the new version into the version DB
self._insert_version(version)
logger.debug('Finished writing versions for %s', symbol)
return VersionedItem(symbol=symbol,
library=self.library_name,
version=version['version'],
metadata=version.pop('metadata', None),
data=None)
def test_versioned_item_str_handles_none():
item = VersionedItem(symbol=None,
library=None,
data=None,
version=None,
metadata=None)
assert str(item)
def test_versioned_item_str():
item = VersionedItem(symbol="sym",
library="ONEMINUTE",
data=pd.DataFrame(),
version=1.0,
metadata={'metadata': 'foo'})
expected = "VersionedItem(symbol=sym,library=ONEMINUTE," + \
"data=<class 'pandas.core.frame.DataFrame'>,version=1.0,metadata={'metadata': 'foo'}"
assert str(item) == expected
assert repr(item) == expected
def _do_read(self, symbol, version, from_version=None, **kwargs):
if version.get('deleted'):
raise NoDataFoundException("No data found for %s in library %s" %
(symbol, self._arctic_lib.get_name()))
handler = self._read_handler(version, symbol)
data = handler.read(self._backing_store,
self.library_name,
version,
symbol,
from_version=from_version,
**kwargs)
return VersionedItem(symbol=symbol,
library=self.library_name,
version=version['version'],
metadata=version.pop('metadata', None),
data=data)