def open(uri=None, mode='a'):
"""Open a Blaze object via an `uri` (Uniform Resource Identifier).
Parameters
----------
uri : str
Specifies the URI for the Blaze object. It can be a regular file too.
mode : the open mode (string)
Specifies the mode in which the object is opened. The supported
values are:
* 'r' for read-only
* 'w' for emptying the previous underlying data
* 'a' for allowing read/write on top of existing data
Returns
-------
out : an Array or Table object.
"""
ARRAY = 1
TABLE = 2
if uri is None:
source = CArraySource()
else:
uri = urlparse(uri)
if uri.scheme == 'carray':
path = os.path.join(uri.netloc, uri.path[1:])
parms = params(storage=path)
source = CArraySource(params=parms)
structure = ARRAY
if uri.scheme == 'ctable':
path = os.path.join(uri.netloc, uri.path[1:])
parms = params(storage=path)
source = CTableSource(params=parms)
structure = TABLE
elif uri.scheme == 'sqlite':
path = os.path.join(uri.netloc, uri.path[1:])
parms = params(storage=path or None)
source = SqliteSource(params=parms)
structure = TABLE
else:
# Default is to treat the URI as a regular path
parms = params(storage=uri.path)
source = CArraySource(params=parms)
structure = ARRAY
# Don't want a deferred array (yet)
# return NDArray(source)
if structure == ARRAY:
return Array(source)
elif structure == TABLE:
return NDTable(source)
def __init__(self,
obj,
dshape=None,
metadata=None,
layout=None,
params=None):
# Datashape
# ---------
if isinstance(dshape, basestring):
dshape = _dshape(dshape)
if not dshape:
# The user just passed in a raw data source, try
# and infer how it should be layed out or fail
# back on dynamic types.
self._datashape = dshape = CTableSource.infer_datashape(obj)
else:
# The user overlayed their custom dshape on this
# data, check if it makes sense
CTableSource.check_datashape(obj, given_dshape=dshape)
self._datashape = dshape
# Source
# ------
if isinstance(obj, ByteProvider):
self.data = obj
else:
self.data = CTableSource(obj, dshape=dshape, params=params)
# children graph nodes
self.children = []
self.space = Space(self.data)
# Layout
# ------
if layout:
self._layout = layout
elif not layout:
self._layout = self.data.default_layout()
# Metadata
# --------
self._metadata = NDTable._metaheader + (metadata or [])
# Parameters
# ----------
self.params = params
def open(uri, mode='a', eclass=_eclass.manifest):
"""Open a Blaze object via an `uri` (Uniform Resource Identifier).
Parameters
----------
uri : str
Specifies the URI for the Blaze object. It can be a regular file too.
The URL scheme indicates the storage type:
* carray: Chunked array
* ctable: Chunked table
* sqlite: SQLite table (the URI 'sqlite://' creates in-memory table)
If no URI scheme is given, carray is assumed.
mode : the open mode (string)
Specifies the mode in which the object is opened. The supported
values are:
* 'r' for read-only
* 'w' for emptying the previous underlying data
* 'a' for allowing read/write on top of existing data
Returns
-------
out : an Array or Table object.
"""
ARRAY = 1
TABLE = 2
uri = urlparse(uri)
path = uri.netloc + uri.path
parms = params(storage=path)
if uri.scheme == 'carray':
source = CArraySource(params=parms)
structure = ARRAY
elif uri.scheme == 'ctable':
source = CTableSource(params=parms)
structure = TABLE
elif uri.scheme == 'sqlite':
# Empty path means memory storage
parms = params(storage=path or None)
source = SqliteSource(params=parms)
structure = TABLE
else:
# Default is to treat the URI as a regular path
parms = params(storage=path)
source = CArraySource(params=parms)
structure = ARRAY
# Don't want a deferred array (yet)
# return NDArray(source)
if structure == ARRAY:
if eclass is _eclass.manifest:
return Array(source)
elif eclass is _eclass.delayed:
return NDArray(source)
elif structure == TABLE:
if eclass is _eclass.manifest:
return Table(source)
elif eclass is _eclass.delayed:
return NDTable(source)
