def register_sampler(data_format, data_class, function, force=False, usage=None):
"""Register a new method to InitialBinaryTable.sampler() for a given format
Parameters
----------
data_format : `str`
name of the format to be registered
data_class : `type`
the class that the sampler returns
function : `callable`
the method to call from :meth:`InitialBinaryTable.sampler`
force : `bool`, optional
overwrite existing registration for ``data_format`` if found,
default: `False`
"""
key = (data_format, data_class)
if key not in _SAMPLERS or force:
_SAMPLERS[key] = (function, usage)
else:
raise IORegistryError(
"Fetcher for format '{0}' and class '{1}' "
"has already been "
"defined".format(data_format, data_class)
)
_update__doc__(data_class)
def get_fetcher(data_format, data_class):
"""Return the :meth:`~EventTable.fetch` function for the given format
Parameters
----------
data_format : `str`
name of the format
data_class : `type`
the class that the fetcher returns
Raises
------
astropy.io.registry.IORegistryError
if not registration is found matching ``data_format``
"""
# this is a copy of astropy.io.regsitry.get_reader
fetchers = [(fmt, cls) for fmt, cls in _FETCHERS if fmt == data_format]
for fetch_fmt, fetch_cls in fetchers:
if io_registry._is_best_match(data_class, fetch_cls, fetchers):
return _FETCHERS[(fetch_fmt, fetch_cls)][0]
else:
formats = [
fmt for fmt, cls in _FETCHERS
if io_registry._is_best_match(fmt, cls, fetchers)
]
formatstr = '\n'.join(sorted(formats))
raise IORegistryError(
"No fetcher definer for format '{0}' and class '{1}'.\n"
"The available formats are:\n{2}".format(data_format,
data_class.__name__,
formatstr))
def get_model(data_format, data_class):
"""Return the :meth:`~KNTable.model` function for the given format
Parameters
----------
data_format : `str`
name of the format
data_class : `type`
the class that the model returns
Raises
------
astropy.io.registry.IORegistryError
if not registration is found matching ``data_format``
"""
try:
return _MODELS[(data_format, data_class)][0]
except KeyError:
formats = '\n'.join(_MODELS.keys())
raise IORegistryError("No model definer for format %r. "
"The available formats are:\n%r" %
(data_format, formats))
def get_sampler(data_format, data_class):
"""Return the :meth:`~InitialBinaryTable.sampler` function for the given format
Parameters
----------
data_format : `str`
name of the format
data_class : `type`
the class that the sampler returns
Raises
------
astropy.io.registry.IORegistryError
if not registration is found matching ``data_format``
"""
try:
return _SAMPLERS[(data_format, data_class)][0]
except KeyError:
formats = '\n'.join(_SAMPLERS.keys())
raise IORegistryError("No sampler definer for format %r. "
"The available formats are:\n%r" %
(data_format, formats))
def test_IORegistryError():
with pytest.raises(IORegistryError, match="just checking"):
raise IORegistryError("just checking")