# get_pkg_data_fileobj¶

astropy.utils.data.get_pkg_data_fileobj(data_name, package=None, encoding=None, cache=True)[source]

Retrieves a data file from the standard locations for the package and provides the file as a file-like object that reads bytes.

Parameters: data_name : str Name/location of the desired data file. One of the following: The name of a data file included in the source distribution. The path is relative to the module calling this function. For example, if calling from astropy.pkname, use 'data/file.dat' to get the file in astropy/pkgname/data/file.dat. Double-dots can be used to go up a level. In the same example, use '../data/file.dat' to get astropy/data/file.dat. If a matching local file does not exist, the Astropy data server will be queried for the file. A hash like that produced by compute_hash can be requested, prefixed by ‘hash/’ e.g. ‘hash/34c33b3eb0d56eb9462003af249eff28’. The hash will first be searched for locally, and if not found, the Astropy data server will be queried. package : str, optional If specified, look for a file relative to the given package, rather than the default of looking relative to the calling module’s package. encoding : str, optional When None (default), returns a file-like object with a read method returns str (unicode) objects, using locale.getpreferredencoding as an encoding. This matches the default behavior of the built-in open when no mode argument is provided. When 'binary', returns a file-like object where its read method returns bytes objects. When another string, it is the name of an encoding, and the file-like object’s read method will return str (unicode) objects, decoded from binary using the given encoding. cache : bool If True, the file will be downloaded and saved locally or the already-cached local copy will be accessed. If False, the file-like object will directly access the resource (e.g. if a remote URL is accessed, an object like that from urllib.request.urlopen is returned). fileobj : file-like An object with the contents of the data file available via read function. Can be used as part of a with statement, automatically closing itself after the with block. urllib2.URLError, urllib.error.URLError If a remote file cannot be found. OSError If problems occur writing or reading a local file.

get_pkg_data_contents
returns the contents of a file or url as a bytes object
get_pkg_data_filename
returns a local name for a file containing the data

Examples

This will retrieve a data file and its contents for the astropy.wcs tests:

>>> from astropy.utils.data import get_pkg_data_fileobj
>>> with get_pkg_data_fileobj('data/3d_cd.hdr',
...                           package='astropy.wcs.tests') as fobj:
...     fcontents = fobj.read()
...


This next example would download a data file from the astropy data server because the allsky/allsky_rosat.fits file is not present in the source distribution. It will also save the file locally so the next time it is accessed it won’t need to be downloaded.:

>>> from astropy.utils.data import get_pkg_data_fileobj
>>> with get_pkg_data_fileobj('allsky/allsky_rosat.fits',
...                           encoding='binary') as fobj:
...     fcontents = fobj.read()
...

>>> with get_pkg_data_fileobj('allsky/allsky_rosat.fits',