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## mutter('registering transport: %s => %s' % (prefix, klass.__name__))
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_protocol_handlers[prefix] = klass
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class Transport(object):
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"""This class encapsulates methods for retrieving or putting a file
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from/to a storage location.
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def abspath(self, relpath):
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"""Return the full url to the given relative path.
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This can be supplied with a string or a list
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XXX: Robert Collins 20051016 - is this really needed in the public
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raise NotImplementedError
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def relpath(self, abspath):
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"""Return the local path portion from a given absolute path.
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This default implementation is not suitable for filesystems with
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aliasing, such as that given by symlinks, where a path may not
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start with our base, but still be a relpath once aliasing is
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raise NotImplementedError
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if not abspath.startswith(self.base):
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raise NonRelativePath('path %r is not under base URL %r'
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% (abspath, self.base))
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return abspath[pl:].lstrip('/')
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def has(self, relpath):
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"""Does the target location exist?"""
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"""Does the file relpath exist?
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Note that some transports MAY allow querying on directories, but this
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is not part of the protocol.
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raise NotImplementedError
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def has_multi(self, relpaths, pb=None):
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yield self.has(relpath)
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def iter_files_recursive(self):
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"""Iter the relative paths of files in the transports sub-tree.
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As with other listing functions, only some transports implement this,.
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you may check via is_listable to determine if it will.
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raise NotImplementedError
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def get(self, relpath):
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"""Get the file at the given relative path.
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yield self.get(relpath)
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def get_partial(self, relpath, start, length=None):
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"""Get just part of a file.
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:param relpath: Path to the file, relative to base
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:param start: The starting position to read from
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:param length: The length to read. A length of None indicates
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read to the end of the file.
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:return: A file-like object containing at least the specified bytes.
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Some implementations may return objects which can be read
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past this length, but this is not guaranteed.
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raise NotImplementedError
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def get_partial_multi(self, offsets, pb=None):
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"""Put a set of files or strings into the location.
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Requesting multiple portions of the same file can be dangerous.
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:param offsets: A list of tuples of relpath, start, length
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[(path1, start1, length1),
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(path2, start2, length2),
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(path3, start3), ...]
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length is optional, defaulting to None
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:param pb: An optional ProgressBar for indicating percent done.
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:return: A generator of file-like objects.
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total = self._get_total(offsets)
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for offset in offsets:
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self._update_pb(pb, 'get_partial', count, total)
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yield self.get_partial(*offset)
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def put(self, relpath, f):
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"""Copy the file-like or string object into the location.
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"""Return the stat information for a file.
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WARNING: This may not be implementable for all protocols, so use
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NOTE: This returns an object with fields such as 'st_size'. It MAY
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or MAY NOT return the literal result of an os.stat() call, so all
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access should be via named fields.
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ALSO NOTE: Stats of directories may not be supported on some
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raise NotImplementedError