diff options
Diffstat (limited to 'src/snakeoil/data_source.py')
| -rw-r--r-- | src/snakeoil/data_source.py | 81 |
1 files changed, 51 insertions, 30 deletions
diff --git a/src/snakeoil/data_source.py b/src/snakeoil/data_source.py index 1faa540..3b0ccb1 100644 --- a/src/snakeoil/data_source.py +++ b/src/snakeoil/data_source.py @@ -33,8 +33,13 @@ we caught the exception. """ __all__ = ( - "base", "bz2_source", "data_source", "local_source", "text_data_source", - "bytes_data_source", "invokable_data_source", + "base", + "bz2_source", + "data_source", + "local_source", + "text_data_source", + "bytes_data_source", + "invokable_data_source", ) import errno @@ -62,10 +67,9 @@ def _mk_writable_cls(base, name): exceptions attribute """ - base_cls = base exceptions = (MemoryError,) - __slots__ = ('_callback',) + __slots__ = ("_callback",) def __init__(self, callback, data): """ @@ -85,6 +89,7 @@ def _mk_writable_cls(base, name): self._callback(self.read()) self._callback = None self.base_cls.close(self) + kls.__name__ = name return kls @@ -100,6 +105,7 @@ class text_ro_StringIO(stringio.text_readonly): Specifically this adds the necessary `exceptions` attribute; see :py:class:`snakeoil.stringio.text_readonly` for methods details. """ + __slots__ = () exceptions = (MemoryError, TypeError) @@ -111,6 +117,7 @@ class bytes_ro_StringIO(stringio.bytes_readonly): Specifically this adds the necessary `exceptions` attribute; see :py:class:`snakeoil.stringio.bytes_readonly` for methods details. """ + __slots__ = () exceptions = (MemoryError, TypeError) @@ -131,6 +138,7 @@ class base: :ivar path: If None, no local path is available- else it's the ondisk path to the data """ + __slots__ = ("weakref",) path = None @@ -155,7 +163,8 @@ class base: def transfer_to_path(self, path): return self.transfer_to_data_source( - local_source(path, mutable=True, encoding=None)) + local_source(path, mutable=True, encoding=None) + ) def transfer_to_data_source(self, write_source): read_f, m, write_f = None, None, None @@ -208,31 +217,32 @@ class local_source(base): raise TypeError("data source %s is immutable" % (self,)) if self.encoding: opener = open_file - opener = post_curry(opener, buffering=self.buffering_window, - encoding=self.encoding) + opener = post_curry( + opener, buffering=self.buffering_window, encoding=self.encoding + ) else: opener = post_curry(open_file, self.buffering_window) if not writable: - return opener(self.path, 'r') + return opener(self.path, "r") try: return opener(self.path, "r+") except IOError as ie: if ie.errno != errno.ENOENT: raise - return opener(self.path, 'w+') + return opener(self.path, "w+") @klass.steal_docs(base) def bytes_fileobj(self, writable=False): if not writable: - return open_file(self.path, 'rb', self.buffering_window) + return open_file(self.path, "rb", self.buffering_window) if not self.mutable: raise TypeError("data source %s is immutable" % (self,)) try: - return open_file(self.path, 'rb+', self.buffering_window) + return open_file(self.path, "rb+", self.buffering_window) except IOError as ie: if ie.errno != errno.ENOENT: raise - return open_file(self.path, 'wb+', self.buffering_window) + return open_file(self.path, "wb+", self.buffering_window) class bz2_source(base): @@ -255,7 +265,8 @@ class bz2_source(base): def text_fileobj(self, writable=False): data = compression.decompress_data( - 'bzip2', fileutils.readfile_bytes(self.path)).decode() + "bzip2", fileutils.readfile_bytes(self.path) + ).decode() if writable: if not self.mutable: raise TypeError(f"data source {self} is not mutable") @@ -263,8 +274,7 @@ class bz2_source(base): return text_ro_StringIO(data) def bytes_fileobj(self, writable=False): - data = compression.decompress_data( - 'bzip2', fileutils.readfile_bytes(self.path)) + data = compression.decompress_data("bzip2", fileutils.readfile_bytes(self.path)) if writable: if not self.mutable: raise TypeError(f"data source {self} is not mutable") @@ -275,7 +285,7 @@ class bz2_source(base): if isinstance(data, str): data = data.encode() with open(self.path, "wb") as f: - f.write(compression.compress_data('bzip2', data)) + f.write(compression.compress_data("bzip2", data)) class data_source(base): @@ -293,7 +303,7 @@ class data_source(base): :ivar path: note that path is None for this class- no on disk location available. """ - __slots__ = ('data', 'mutable') + __slots__ = ("data", "mutable") def __init__(self, data, mutable=False): """ @@ -305,7 +315,7 @@ class data_source(base): self.mutable = mutable def _convert_data(self, mode): - if mode == 'bytes': + if mode == "bytes": if isinstance(self.data, bytes): return self.data return self.data.encode() @@ -318,9 +328,8 @@ class data_source(base): if writable: if not self.mutable: raise TypeError(f"data source {self} is not mutable") - return text_wr_StringIO(self._reset_data, - self._convert_data('text')) - return text_ro_StringIO(self._convert_data('text')) + return text_wr_StringIO(self._reset_data, self._convert_data("text")) + return text_ro_StringIO(self._convert_data("text")) def _reset_data(self, data): if isinstance(self.data, bytes): @@ -335,9 +344,8 @@ class data_source(base): if writable: if not self.mutable: raise TypeError(f"data source {self} is not mutable") - return bytes_wr_StringIO(self._reset_data, - self._convert_data('bytes')) - return bytes_ro_StringIO(self._convert_data('bytes')) + return bytes_wr_StringIO(self._reset_data, self._convert_data("bytes")) + return bytes_ro_StringIO(self._convert_data("bytes")) class text_data_source(data_source): @@ -355,7 +363,7 @@ class text_data_source(data_source): data_source.__init__(self, data, mutable=mutable) def _convert_data(self, mode): - if mode != 'bytes': + if mode != "bytes": return self.data return self.data.encode() @@ -375,7 +383,7 @@ class bytes_data_source(data_source): data_source.__init__(self, data, mutable=mutable) def _convert_data(self, mode): - if mode == 'bytes': + if mode == "bytes": return self.data return self.data.decode() @@ -390,6 +398,7 @@ class invokable_data_source(data_source): Note that this instance is explicitly readonly. """ + __slots__ = () def __init__(self, data): @@ -412,7 +421,9 @@ class invokable_data_source(data_source): return self.data(False) @classmethod - def wrap_function(cls, invokable, returns_text=True, returns_handle=False, encoding_hint=None): + def wrap_function( + cls, invokable, returns_text=True, returns_handle=False, encoding_hint=None + ): """ Helper function to automatically convert a function that returns text or bytes into appropriate callable @@ -425,10 +436,20 @@ class invokable_data_source(data_source): :param encoding_hint: the preferred encoding to use for encoding :return: invokable_data_source instance """ - return cls(partial(cls._simple_wrapper, invokable, encoding_hint, returns_text, returns_handle)) + return cls( + partial( + cls._simple_wrapper, + invokable, + encoding_hint, + returns_text, + returns_handle, + ) + ) @staticmethod - def _simple_wrapper(invokable, encoding_hint, returns_text, returns_handle, text_wanted): + def _simple_wrapper( + invokable, encoding_hint, returns_text, returns_handle, text_wanted + ): data = invokable() if returns_text != text_wanted: if text_wanted: @@ -446,7 +467,7 @@ class invokable_data_source(data_source): data = data.read() if encoding_hint is None: # fallback to utf8 - encoding_hint = 'utf8' + encoding_hint = "utf8" data = data.encode(encoding_hint) elif returns_handle: return data |