FileOpener

class baseband.base.base.FileOpener(fmt, classes, header_class)

Bases: object

File opener for a baseband format.

Each instance can be used as a function to open a baseband stream. It is probably best used inside a wrapper, so that the documentation can reflect the docstring of __call__ rather than of this class.

Parameters:

fmtstr

Name of the baseband format

classesdict

With the file/stream reader/writer classes keyed by names equal to ‘FileReader’, ‘FileWriter’, ‘StreamReader’, ‘StreamWriter’ prefixed by fmt. Typically, one will pass in classes=globals().

header_classVLBIHeaderBase subclass

Used to instantiate a header from keywords as needed.

Attributes Summary

non_header_keys

keyword arguments that should never be used to create a header.

Methods Summary

__call__(name[, mode])	Open baseband file(s) for reading or writing.
create(ns[, doc])	Create a standard opener for the given namespace.
get_fh(name, mode[, kwargs])	Ensure name is a filehandle, opening it if necessary.
get_fns(name, mode, kwargs)	Convert a template into a file-name sequencer.
get_header0(kwargs)	Get header0 from kwargs or construct it from kwargs.
get_type(name)	Infer the type of file name is pointing to.
is_fh(name)	Whether name is a filehandle.
is_name(name)	Whether name is a name of a file.
is_sequence(name)	Whether name is an (implied) sequence of files.
is_template(name)	Whether name is a template for a sequence of files.
normalize_mode(mode)
wrapped([module, doc])	Wrap as a function named open, replacing docstring and module.

Attributes Documentation

non_header_keys = {'file_size', 'fill_value', 'squeeze', 'subset', 'verify'}

keyword arguments that should never be used to create a header.

Methods Documentation

__call__(name, mode='rs', **kwargs)

Open baseband file(s) for reading or writing.

Opened as a binary file, one gets a wrapped filehandle that adds methods to read/write a frame. Opened as a stream, the handle is wrapped further, with methods such as reading and writing to the file as if it were a stream of samples.

Parameters:

namestr or filehandle, or sequence of str

File name, filehandle, sequence of file names, or template (file name(s) can be Path but template has to be str).

mode{‘rb’, ‘wb’, ‘rs’, or ‘ws’}, optional

Whether to open for reading or writing, and as a regular binary file or as a stream. Default: ‘rs’, for reading a stream.

**kwargs

Additional arguments when opening the file as a stream.

classmethod create(ns, doc=None)

Create a standard opener for the given namespace.

This assumes that the namespace contains file and stream readers and writers, as well as a header class, with standard names, <fmt>FileReader, <fmt>FileWriter, <fmt>StreamReader, <fmt>StreamWriter, and <fmt>Header, where fmt is the name of the format (which is inferred by looking for a *StreamReader entry).

The opener is instantiated using the format and the above classes, and then a wrapping function is created with __module__ set to the __name__ of the namespace, and with the documentation of its __call__ method extended with doc.

Parameters:

nsdict

Namespace to look in. Generally, pass in globals() at the call site.

docstr, optional

Extra documentation to add to that of the opener’s __call__ method.

get_fh(name, mode, kwargs={})

Ensure name is a filehandle, opening it if necessary.

get_fns(name, mode, kwargs)

Convert a template into a file-name sequencer.

Any keywords needed to fill the template are popped from kwargs.

get_header0(kwargs)

Get header0 from kwargs or construct it from kwargs.

Possible keyword arguments will be popped from kwargs.

get_type(name)

Infer the type of file name is pointing to.

Options are ‘fh’, ‘name’, ‘sequence’, and ‘template’.

is_fh(name)

Whether name is a filehandle.

is_name(name)

Whether name is a name of a file.

is_sequence(name)

Whether name is an (implied) sequence of files.

is_template(name)

Whether name is a template for a sequence of files.

normalize_mode(mode)

wrapped(module=None, doc=None)

Wrap as a function named open, replacing docstring and module.