from allmydata.storage.server import si_a2b, si_b2a
from allmydata.util import base32, hashutil
from allmydata.interfaces import IURI, IDirnodeURI, IFileURI, IImmutableFileURI, \
- IVerifierURI, IMutableFileURI, IDirectoryURI, IReadonlyDirectoryURI
+ IVerifierURI, IMutableFileURI, IDirectoryURI, IReadonlyDirectoryURI, \
+ MustBeDeepImmutableError, MustBeReadonlyError, CapConstraintError
-class BadURIError(Exception):
+class BadURIError(CapConstraintError):
pass
-# the URI shall be an ascii representation of the file. It shall contain
-# enough information to retrieve and validate the contents. It shall be
-# expressed in a limited character set (namely [TODO]).
+# The URI shall be an ASCII representation of a reference to the file/directory.
+# It shall contain enough information to retrieve and validate the contents.
+# It shall be expressed in a limited character set (currently base32 plus ':' and
+# capital letters, but future URIs might use a larger charset).
+
+# TODO:
+# - rename all of the *URI classes/interfaces to *Cap
+# - make variable and method names consistently use _uri for an URI string,
+# and _cap for a Cap object (decoded URI)
+# - remove the human_encoding methods?
BASE32STR_128bits = '(%s{25}%s)' % (base32.BASE32CHAR, base32.BASE32CHAR_3bits)
BASE32STR_256bits = '(%s{51}%s)' % (base32.BASE32CHAR, base32.BASE32CHAR_1bits)
NUMBER='([0-9]+)'
NUMBER_IGNORE='(?:[0-9]+)'
-# URIs (soon to be renamed "caps") are always allowed to come with a leading
+# "human-encoded" URIs are allowed to come with a leading
# 'http://127.0.0.1:(8123|3456)/uri/' that will be ignored.
+# Note that nothing in the Tahoe code currently uses the human encoding.
OPTIONALHTTPLEAD=r'(?:https?://(?:[^:/]+)(?::%s)?/uri/)?' % NUMBER_IGNORE
class _BaseURI:
def __hash__(self):
return self.to_string().__hash__()
+
def __eq__(self, them):
if isinstance(them, _BaseURI):
return self.to_string() == them.to_string()
else:
return False
+
def __ne__(self, them):
if isinstance(them, _BaseURI):
return self.to_string() != them.to_string()
else:
return True
+
def to_human_encoding(self):
return 'http://127.0.0.1:3456/uri/'+self.to_string()
def get_storage_index(self):
return self.storage_index
+
class CHKFileURI(_BaseURI):
implements(IURI, IImmutableFileURI)
def init_from_human_encoding(cls, uri):
mo = cls.HUMAN_RE.search(uri)
if not mo:
- raise BadURIError("%s doesn't look like a cap" % (uri,))
+ raise BadURIError("'%s' doesn't look like a %s cap" % (uri, cls))
return cls(base32.a2b(mo.group(1)), base32.a2b(mo.group(2)),
int(mo.group(3)), int(mo.group(4)), int(mo.group(5)))
def init_from_string(cls, uri):
mo = cls.STRING_RE.search(uri)
if not mo:
- raise BadURIError("%s doesn't look like a cap" % (uri,))
+ raise BadURIError("'%s' doesn't look like a %s cap" % (uri, cls))
return cls(base32.a2b(mo.group(1)), base32.a2b(mo.group(2)),
int(mo.group(3)), int(mo.group(4)), int(mo.group(5)))
def is_readonly(self):
return True
+
def is_mutable(self):
return False
+
def get_readonly(self):
return self
class CHKFileVerifierURI(_BaseURI):
implements(IVerifierURI)
+ BASE_STRING='URI:CHK-Verifier:'
STRING_RE=re.compile('^URI:CHK-Verifier:'+BASE32STR_128bits+':'+
BASE32STR_256bits+':'+NUMBER+':'+NUMBER+':'+NUMBER)
HUMAN_RE=re.compile('^'+OPTIONALHTTPLEAD+'URI'+SEP+'CHK-Verifier'+SEP+
@classmethod
def init_from_human_encoding(cls, uri):
mo = cls.HUMAN_RE.search(uri)
- assert mo, uri
+ if not mo:
+ raise BadURIError("'%s' doesn't look like a %s cap" % (uri, cls))
return cls(base32.a2b(mo.group(1)), base32.a2b(mo.group(2)),
int(mo.group(3)), int(mo.group(4)), int(mo.group(5)))
@classmethod
def init_from_string(cls, uri):
mo = cls.STRING_RE.search(uri)
- assert mo, (uri, cls, cls.STRING_RE)
+ if not mo:
+ raise BadURIError("'%s' doesn't look like a %s cap" % (uri, cls))
return cls(si_a2b(mo.group(1)), base32.a2b(mo.group(2)),
int(mo.group(3)), int(mo.group(4)), int(mo.group(5)))
self.total_shares,
self.size))
+ def is_readonly(self):
+ return True
+
+ def is_mutable(self):
+ return False
+
+ def get_readonly(self):
+ return self
+
+ def get_verify_cap(self):
+ return self
+
class LiteralFileURI(_BaseURI):
implements(IURI, IImmutableFileURI)
def __init__(self, data=None):
if data is not None:
+ assert isinstance(data, str)
self.data = data
@classmethod
def init_from_human_encoding(cls, uri):
mo = cls.HUMAN_RE.search(uri)
- assert mo, uri
+ if not mo:
+ raise BadURIError("'%s' doesn't look like a %s cap" % (uri, cls))
return cls(base32.a2b(mo.group(1)))
@classmethod
def init_from_string(cls, uri):
mo = cls.STRING_RE.search(uri)
- assert mo, uri
+ if not mo:
+ raise BadURIError("'%s' doesn't look like a %s cap" % (uri, cls))
return cls(base32.a2b(mo.group(1)))
def to_string(self):
def is_readonly(self):
return True
+
def is_mutable(self):
return False
+
def get_readonly(self):
return self
+
def get_storage_index(self):
return None
def get_size(self):
return len(self.data)
+
class WriteableSSKFileURI(_BaseURI):
implements(IURI, IMutableFileURI)
def init_from_human_encoding(cls, uri):
mo = cls.HUMAN_RE.search(uri)
if not mo:
- raise BadURIError("'%s' doesn't look like a cap" % (uri,))
+ raise BadURIError("'%s' doesn't look like a %s cap" % (uri, cls))
return cls(base32.a2b(mo.group(1)), base32.a2b(mo.group(2)))
@classmethod
def abbrev(self):
return base32.b2a(self.writekey[:5])
+
def abbrev_si(self):
return base32.b2a(self.storage_index)[:5]
def is_readonly(self):
return False
+
def is_mutable(self):
return True
+
def get_readonly(self):
return ReadonlySSKFileURI(self.readkey, self.fingerprint)
+
def get_verify_cap(self):
return SSKVerifierURI(self.storage_index, self.fingerprint)
def init_from_human_encoding(cls, uri):
mo = cls.HUMAN_RE.search(uri)
if not mo:
- raise BadURIError("'%s' doesn't look like a cap" % (uri,))
+ raise BadURIError("'%s' doesn't look like a %s cap" % (uri, cls))
return cls(base32.a2b(mo.group(1)), base32.a2b(mo.group(2)))
@classmethod
def init_from_string(cls, uri):
mo = cls.STRING_RE.search(uri)
if not mo:
- raise BadURIError("'%s' doesn't look like a cap" % (uri,))
+ raise BadURIError("'%s' doesn't look like a %s cap" % (uri, cls))
return cls(base32.a2b(mo.group(1)), base32.a2b(mo.group(2)))
def to_string(self):
def abbrev(self):
return base32.b2a(self.readkey[:5])
+
def abbrev_si(self):
return base32.b2a(self.storage_index)[:5]
def is_readonly(self):
return True
+
def is_mutable(self):
return True
+
def get_readonly(self):
return self
+
def get_verify_cap(self):
return SSKVerifierURI(self.storage_index, self.fingerprint)
@classmethod
def init_from_human_encoding(cls, uri):
mo = cls.HUMAN_RE.search(uri)
- assert mo, uri
+ if not mo:
+ raise BadURIError("'%s' doesn't look like a %s cap" % (uri, cls))
return cls(si_a2b(mo.group(1)), base32.a2b(mo.group(2)))
@classmethod
def init_from_string(cls, uri):
mo = cls.STRING_RE.search(uri)
- assert mo, (uri, cls)
+ if not mo:
+ raise BadURIError("'%s' doesn't look like a %s cap" % (uri, cls))
return cls(si_a2b(mo.group(1)), base32.a2b(mo.group(2)))
def to_string(self):
return 'URI:SSK-Verifier:%s:%s' % (si_b2a(self.storage_index),
base32.b2a(self.fingerprint))
+ def is_readonly(self):
+ return True
+
+ def is_mutable(self):
+ return False
+
+ def get_readonly(self):
+ return self
+
+ def get_verify_cap(self):
+ return self
+
+class WriteableMDMFFileURI(_BaseURI):
+ implements(IURI, IMutableFileURI)
+
+ BASE_STRING='URI:MDMF:'
+ STRING_RE=re.compile('^'+BASE_STRING+BASE32STR_128bits+':'+BASE32STR_256bits+'(:|$)')
+ HUMAN_RE=re.compile('^'+OPTIONALHTTPLEAD+'URI'+SEP+'MDMF'+SEP+BASE32STR_128bits+SEP+BASE32STR_256bits+'(:|$)')
+
+ def __init__(self, writekey, fingerprint):
+ self.writekey = writekey
+ self.readkey = hashutil.ssk_readkey_hash(writekey)
+ self.storage_index = hashutil.ssk_storage_index_hash(self.readkey)
+ assert len(self.storage_index) == 16
+ self.fingerprint = fingerprint
+
+ @classmethod
+ def init_from_human_encoding(cls, uri):
+ mo = cls.HUMAN_RE.search(uri)
+ if not mo:
+ raise BadURIError("'%s' doesn't look like a %s cap" % (uri, cls))
+ return cls(base32.a2b(mo.group(1)), base32.a2b(mo.group(2)))
+
+ @classmethod
+ def init_from_string(cls, uri):
+ mo = cls.STRING_RE.search(uri)
+ if not mo:
+ raise BadURIError("'%s' doesn't look like a %s cap" % (uri, cls))
+ return cls(base32.a2b(mo.group(1)), base32.a2b(mo.group(2)))
+
+ def to_string(self):
+ assert isinstance(self.writekey, str)
+ assert isinstance(self.fingerprint, str)
+ ret = 'URI:MDMF:%s:%s' % (base32.b2a(self.writekey),
+ base32.b2a(self.fingerprint))
+ return ret
+
+ def __repr__(self):
+ return "<%s %s>" % (self.__class__.__name__, self.abbrev())
+
+ def abbrev(self):
+ return base32.b2a(self.writekey[:5])
+
+ def abbrev_si(self):
+ return base32.b2a(self.storage_index)[:5]
+
+ def is_readonly(self):
+ return False
+
+ def is_mutable(self):
+ return True
+
+ def get_readonly(self):
+ return ReadonlyMDMFFileURI(self.readkey, self.fingerprint)
+
+ def get_verify_cap(self):
+ return MDMFVerifierURI(self.storage_index, self.fingerprint)
+
+class ReadonlyMDMFFileURI(_BaseURI):
+ implements(IURI, IMutableFileURI)
+
+ BASE_STRING='URI:MDMF-RO:'
+ STRING_RE=re.compile('^' +BASE_STRING+BASE32STR_128bits+':'+BASE32STR_256bits+'(:|$)')
+ HUMAN_RE=re.compile('^'+OPTIONALHTTPLEAD+'URI'+SEP+'MDMF-RO'+SEP+BASE32STR_128bits+SEP+BASE32STR_256bits+'(:|$)')
+
+ def __init__(self, readkey, fingerprint):
+ self.readkey = readkey
+ self.storage_index = hashutil.ssk_storage_index_hash(self.readkey)
+ assert len(self.storage_index) == 16
+ self.fingerprint = fingerprint
+
+ @classmethod
+ def init_from_human_encoding(cls, uri):
+ mo = cls.HUMAN_RE.search(uri)
+ if not mo:
+ raise BadURIError("'%s' doesn't look like a %s cap" % (uri, cls))
+ return cls(base32.a2b(mo.group(1)), base32.a2b(mo.group(2)))
+
+ @classmethod
+ def init_from_string(cls, uri):
+ mo = cls.STRING_RE.search(uri)
+ if not mo:
+ raise BadURIError("'%s' doesn't look like a %s cap" % (uri, cls))
+
+ return cls(base32.a2b(mo.group(1)), base32.a2b(mo.group(2)))
+
+ def to_string(self):
+ assert isinstance(self.readkey, str)
+ assert isinstance(self.fingerprint, str)
+ ret = 'URI:MDMF-RO:%s:%s' % (base32.b2a(self.readkey),
+ base32.b2a(self.fingerprint))
+ return ret
+
+ def __repr__(self):
+ return "<%s %s>" % (self.__class__.__name__, self.abbrev())
+
+ def abbrev(self):
+ return base32.b2a(self.readkey[:5])
+
+ def abbrev_si(self):
+ return base32.b2a(self.storage_index)[:5]
+
+ def is_readonly(self):
+ return True
+
+ def is_mutable(self):
+ return True
+
+ def get_readonly(self):
+ return self
+
+ def get_verify_cap(self):
+ return MDMFVerifierURI(self.storage_index, self.fingerprint)
+
+class MDMFVerifierURI(_BaseURI):
+ implements(IVerifierURI)
+
+ BASE_STRING='URI:MDMF-Verifier:'
+ STRING_RE=re.compile('^'+BASE_STRING+BASE32STR_128bits+':'+BASE32STR_256bits+'(:|$)')
+ HUMAN_RE=re.compile('^'+OPTIONALHTTPLEAD+'URI'+SEP+'MDMF-Verifier'+SEP+BASE32STR_128bits+SEP+BASE32STR_256bits+'(:|$)')
+
+ def __init__(self, storage_index, fingerprint):
+ assert len(storage_index) == 16
+ self.storage_index = storage_index
+ self.fingerprint = fingerprint
+
+ @classmethod
+ def init_from_human_encoding(cls, uri):
+ mo = cls.HUMAN_RE.search(uri)
+ if not mo:
+ raise BadURIError("'%s' doesn't look like a %s cap" % (uri, cls))
+ return cls(si_a2b(mo.group(1)), base32.a2b(mo.group(2)))
+
+ @classmethod
+ def init_from_string(cls, uri):
+ mo = cls.STRING_RE.search(uri)
+ if not mo:
+ raise BadURIError("'%s' doesn't look like a %s cap" % (uri, cls))
+ return cls(si_a2b(mo.group(1)), base32.a2b(mo.group(2)))
+
+ def to_string(self):
+ assert isinstance(self.storage_index, str)
+ assert isinstance(self.fingerprint, str)
+ ret = 'URI:MDMF-Verifier:%s:%s' % (si_b2a(self.storage_index),
+ base32.b2a(self.fingerprint))
+ return ret
+
+ def is_readonly(self):
+ return True
+
+ def is_mutable(self):
+ return False
+
+ def get_readonly(self):
+ return self
+
+ def get_verify_cap(self):
+ return self
+
class _DirectoryBaseURI(_BaseURI):
implements(IURI, IDirnodeURI)
def __init__(self, filenode_uri=None):
def abbrev(self):
return self._filenode_uri.to_string().split(':')[2][:5]
- def abbrev_si(self):
- return base32.b2a(self._filenode_uri.storage_index)[:5]
- def get_filenode_uri(self):
- return self._filenode_uri
+ def abbrev_si(self):
+ si = self._filenode_uri.get_storage_index()
+ if si is None:
+ return "<LIT>"
+ return base32.b2a(si)[:5]
def is_mutable(self):
return True
+ def get_filenode_cap(self):
+ return self._filenode_uri
+
def get_verify_cap(self):
return DirectoryURIVerifier(self._filenode_uri.get_verify_cap())
def get_readonly(self):
return ReadonlyDirectoryURI(self._filenode_uri.get_readonly())
+
class ReadonlyDirectoryURI(_DirectoryBaseURI):
implements(IReadonlyDirectoryURI)
def get_readonly(self):
return self
+
class _ImmutableDirectoryBaseURI(_DirectoryBaseURI):
def __init__(self, filenode_uri=None):
if filenode_uri:
assert isinstance(filenode_uri, self.INNER_URI_CLASS), filenode_uri
+ assert not filenode_uri.is_mutable()
_DirectoryBaseURI.__init__(self, filenode_uri)
- def is_mutable(self):
- return False
-
def is_readonly(self):
return True
+ def is_mutable(self):
+ return False
+
def get_readonly(self):
return self
+
class ImmutableDirectoryURI(_ImmutableDirectoryBaseURI):
BASE_STRING='URI:DIR2-CHK:'
BASE_STRING_RE=re.compile('^'+BASE_STRING)
BASE_HUMAN_RE=re.compile('^'+OPTIONALHTTPLEAD+'URI'+SEP+'DIR2-CHK'+SEP)
INNER_URI_CLASS=CHKFileURI
+
def get_verify_cap(self):
vcap = self._filenode_uri.get_verify_cap()
return ImmutableDirectoryURIVerifier(vcap)
BASE_STRING_RE=re.compile('^'+BASE_STRING)
BASE_HUMAN_RE=re.compile('^'+OPTIONALHTTPLEAD+'URI'+SEP+'DIR2-LIT'+SEP)
INNER_URI_CLASS=LiteralFileURI
- def __init__(self, data=None):
- filenode_uri = LiteralFileURI(data)
- _ImmutableDirectoryBaseURI.__init__(self, filenode_uri)
+
def get_verify_cap(self):
# LIT caps have no verifier, since they aren't distributed
return None
+class MDMFDirectoryURI(_DirectoryBaseURI):
+ implements(IDirectoryURI)
+
+ BASE_STRING='URI:DIR2-MDMF:'
+ BASE_STRING_RE=re.compile('^'+BASE_STRING)
+ BASE_HUMAN_RE=re.compile('^'+OPTIONALHTTPLEAD+'URI'+SEP+'DIR2-MDMF'+SEP)
+ INNER_URI_CLASS=WriteableMDMFFileURI
+
+ def __init__(self, filenode_uri=None):
+ if filenode_uri:
+ assert not filenode_uri.is_readonly()
+ _DirectoryBaseURI.__init__(self, filenode_uri)
+
+ def is_readonly(self):
+ return False
+
+ def get_readonly(self):
+ return ReadonlyMDMFDirectoryURI(self._filenode_uri.get_readonly())
+
+ def get_verify_cap(self):
+ return MDMFDirectoryURIVerifier(self._filenode_uri.get_verify_cap())
+
+
+class ReadonlyMDMFDirectoryURI(_DirectoryBaseURI):
+ implements(IReadonlyDirectoryURI)
+
+ BASE_STRING='URI:DIR2-MDMF-RO:'
+ BASE_STRING_RE=re.compile('^'+BASE_STRING)
+ BASE_HUMAN_RE=re.compile('^'+OPTIONALHTTPLEAD+'URI'+SEP+'DIR2-MDMF-RO'+SEP)
+ INNER_URI_CLASS=ReadonlyMDMFFileURI
+
+ def __init__(self, filenode_uri=None):
+ if filenode_uri:
+ assert filenode_uri.is_readonly()
+ _DirectoryBaseURI.__init__(self, filenode_uri)
+
+ def is_readonly(self):
+ return True
+
+ def get_readonly(self):
+ return self
+
+ def get_verify_cap(self):
+ return MDMFDirectoryURIVerifier(self._filenode_uri.get_verify_cap())
+
+def wrap_dirnode_cap(filecap):
+ if isinstance(filecap, WriteableSSKFileURI):
+ return DirectoryURI(filecap)
+ if isinstance(filecap, ReadonlySSKFileURI):
+ return ReadonlyDirectoryURI(filecap)
+ if isinstance(filecap, CHKFileURI):
+ return ImmutableDirectoryURI(filecap)
+ if isinstance(filecap, LiteralFileURI):
+ return LiteralDirectoryURI(filecap)
+ if isinstance(filecap, WriteableMDMFFileURI):
+ return MDMFDirectoryURI(filecap)
+ if isinstance(filecap, ReadonlyMDMFFileURI):
+ return ReadonlyMDMFDirectoryURI(filecap)
+ assert False, "cannot interpret as a directory cap: %s" % filecap.__class__
+
+class MDMFDirectoryURIVerifier(_DirectoryBaseURI):
+ implements(IVerifierURI)
+
+ BASE_STRING='URI:DIR2-MDMF-Verifier:'
+ BASE_STRING_RE=re.compile('^'+BASE_STRING)
+ BASE_HUMAN_RE=re.compile('^'+OPTIONALHTTPLEAD+'URI'+SEP+'DIR2-MDMF-Verifier'+SEP)
+ INNER_URI_CLASS=MDMFVerifierURI
+
+ def __init__(self, filenode_uri=None):
+ if filenode_uri:
+ assert IVerifierURI.providedBy(filenode_uri)
+ self._filenode_uri = filenode_uri
+
+ def get_filenode_cap(self):
+ return self._filenode_uri
+
+ def is_mutable(self):
+ return False
+
+ def is_readonly(self):
+ return True
+
+ def get_readonly(self):
+ return self
+
+
class DirectoryURIVerifier(_DirectoryBaseURI):
implements(IVerifierURI)
def __init__(self, filenode_uri=None):
if filenode_uri:
- filenode_uri = IVerifierURI(filenode_uri)
+ assert IVerifierURI.providedBy(filenode_uri)
self._filenode_uri = filenode_uri
- def get_filenode_uri(self):
+ def get_filenode_cap(self):
return self._filenode_uri
+ def is_mutable(self):
+ return False
+
+ def is_readonly(self):
+ return True
+
+ def get_readonly(self):
+ return self
+
+
class ImmutableDirectoryURIVerifier(DirectoryURIVerifier):
implements(IVerifierURI)
BASE_STRING='URI:DIR2-CHK-Verifier:'
BASE_HUMAN_RE=re.compile('^'+OPTIONALHTTPLEAD+'URI'+SEP+'DIR2-CHK-VERIFIER'+SEP)
INNER_URI_CLASS=CHKFileVerifierURI
+
class UnknownURI:
- def __init__(self, uri):
+ def __init__(self, uri, error=None):
self._uri = uri
+ self._error = error
+
def to_string(self):
return self._uri
-def from_string(s):
- if not isinstance(s, str):
- raise TypeError("unknown URI type: %s.." % str(s)[:100])
- elif s.startswith('URI:CHK:'):
- return CHKFileURI.init_from_string(s)
- elif s.startswith('URI:CHK-Verifier:'):
- return CHKFileVerifierURI.init_from_string(s)
- elif s.startswith('URI:LIT:'):
- return LiteralFileURI.init_from_string(s)
- elif s.startswith('URI:SSK:'):
- return WriteableSSKFileURI.init_from_string(s)
- elif s.startswith('URI:SSK-RO:'):
- return ReadonlySSKFileURI.init_from_string(s)
- elif s.startswith('URI:SSK-Verifier:'):
- return SSKVerifierURI.init_from_string(s)
- elif s.startswith('URI:DIR2:'):
- return DirectoryURI.init_from_string(s)
- elif s.startswith('URI:DIR2-RO:'):
- return ReadonlyDirectoryURI.init_from_string(s)
- elif s.startswith('URI:DIR2-Verifier:'):
- return DirectoryURIVerifier.init_from_string(s)
- elif s.startswith('URI:DIR2-CHK:'):
- return ImmutableDirectoryURI.init_from_string(s)
- elif s.startswith('URI:DIR2-LIT:'):
- return LiteralDirectoryURI.init_from_string(s)
- return UnknownURI(s)
+ def get_readonly(self):
+ return None
+
+ def get_error(self):
+ return self._error
+
+ def get_verify_cap(self):
+ return None
+
+
+ALLEGED_READONLY_PREFIX = 'ro.'
+ALLEGED_IMMUTABLE_PREFIX = 'imm.'
+
+def from_string(u, deep_immutable=False, name=u"<unknown name>"):
+ if not isinstance(u, str):
+ raise TypeError("unknown URI type: %s.." % str(u)[:100])
+
+ # We allow and check ALLEGED_READONLY_PREFIX or ALLEGED_IMMUTABLE_PREFIX
+ # on all URIs, even though we would only strictly need to do so for caps of
+ # new formats (post Tahoe-LAFS 1.6). URIs that are not consistent with their
+ # prefix are treated as unknown. This should be revisited when we add the
+ # new cap formats. See <http://allmydata.org/trac/tahoe/ticket/833#comment:31>.
+ s = u
+ can_be_mutable = can_be_writeable = not deep_immutable
+ if s.startswith(ALLEGED_IMMUTABLE_PREFIX):
+ can_be_mutable = can_be_writeable = False
+ s = s[len(ALLEGED_IMMUTABLE_PREFIX):]
+ elif s.startswith(ALLEGED_READONLY_PREFIX):
+ can_be_writeable = False
+ s = s[len(ALLEGED_READONLY_PREFIX):]
+
+ error = None
+ kind = "cap"
+ try:
+ if s.startswith('URI:CHK:'):
+ return CHKFileURI.init_from_string(s)
+ elif s.startswith('URI:CHK-Verifier:'):
+ return CHKFileVerifierURI.init_from_string(s)
+ elif s.startswith('URI:LIT:'):
+ return LiteralFileURI.init_from_string(s)
+ elif s.startswith('URI:SSK:'):
+ if can_be_writeable:
+ return WriteableSSKFileURI.init_from_string(s)
+ kind = "URI:SSK file writecap"
+ elif s.startswith('URI:SSK-RO:'):
+ if can_be_mutable:
+ return ReadonlySSKFileURI.init_from_string(s)
+ kind = "URI:SSK-RO readcap to a mutable file"
+ elif s.startswith('URI:SSK-Verifier:'):
+ return SSKVerifierURI.init_from_string(s)
+ elif s.startswith('URI:MDMF:'):
+ if can_be_writeable:
+ return WriteableMDMFFileURI.init_from_string(s)
+ kind = "URI:MDMF file writecap"
+ elif s.startswith('URI:MDMF-RO:'):
+ if can_be_mutable:
+ return ReadonlyMDMFFileURI.init_from_string(s)
+ kind = "URI:MDMF-RO readcap to a mutable file"
+ elif s.startswith('URI:MDMF-Verifier:'):
+ return MDMFVerifierURI.init_from_string(s)
+ elif s.startswith('URI:DIR2:'):
+ if can_be_writeable:
+ return DirectoryURI.init_from_string(s)
+ kind = "URI:DIR2 directory writecap"
+ elif s.startswith('URI:DIR2-RO:'):
+ if can_be_mutable:
+ return ReadonlyDirectoryURI.init_from_string(s)
+ kind = "URI:DIR2-RO readcap to a mutable directory"
+ elif s.startswith('URI:DIR2-Verifier:'):
+ return DirectoryURIVerifier.init_from_string(s)
+ elif s.startswith('URI:DIR2-CHK:'):
+ return ImmutableDirectoryURI.init_from_string(s)
+ elif s.startswith('URI:DIR2-CHK-Verifier:'):
+ return ImmutableDirectoryURIVerifier.init_from_string(s)
+ elif s.startswith('URI:DIR2-LIT:'):
+ return LiteralDirectoryURI.init_from_string(s)
+ elif s.startswith('URI:DIR2-MDMF:'):
+ if can_be_writeable:
+ return MDMFDirectoryURI.init_from_string(s)
+ kind = "URI:DIR2-MDMF directory writecap"
+ elif s.startswith('URI:DIR2-MDMF-RO:'):
+ if can_be_mutable:
+ return ReadonlyMDMFDirectoryURI.init_from_string(s)
+ kind = "URI:DIR2-MDMF-RO readcap to a mutable directory"
+ elif s.startswith('URI:DIR2-MDMF-Verifier:'):
+ return MDMFDirectoryURIVerifier.init_from_string(s)
+ elif s.startswith('x-tahoe-future-test-writeable:') and not can_be_writeable:
+ # For testing how future writeable caps would behave in read-only contexts.
+ kind = "x-tahoe-future-test-writeable: testing cap"
+ elif s.startswith('x-tahoe-future-test-mutable:') and not can_be_mutable:
+ # For testing how future mutable readcaps would behave in immutable contexts.
+ kind = "x-tahoe-future-test-mutable: testing cap"
+ else:
+ return UnknownURI(u)
+
+ # We fell through because a constraint was not met.
+ # Prefer to report the most specific constraint.
+ if not can_be_mutable:
+ error = MustBeDeepImmutableError(kind + " used in an immutable context", name)
+ else:
+ error = MustBeReadonlyError(kind + " used in a read-only context", name)
+
+ except BadURIError, e:
+ error = e
+
+ return UnknownURI(u, error=error)
def is_uri(s):
try:
- uri = from_string(s)
+ from_string(s, deep_immutable=False)
return True
except (TypeError, AssertionError):
return False
-def from_string_dirnode(s):
- u = from_string(s)
+def is_literal_file_uri(s):
+ if not isinstance(s, str):
+ return False
+ return (s.startswith('URI:LIT:') or
+ s.startswith(ALLEGED_READONLY_PREFIX + 'URI:LIT:') or
+ s.startswith(ALLEGED_IMMUTABLE_PREFIX + 'URI:LIT:'))
+
+def has_uri_prefix(s):
+ if not isinstance(s, str):
+ return False
+ return (s.startswith("URI:") or
+ s.startswith(ALLEGED_READONLY_PREFIX + 'URI:') or
+ s.startswith(ALLEGED_IMMUTABLE_PREFIX + 'URI:'))
+
+
+# These take the same keyword arguments as from_string above.
+
+def from_string_dirnode(s, **kwargs):
+ u = from_string(s, **kwargs)
assert IDirnodeURI.providedBy(u)
return u
registerAdapter(from_string_dirnode, str, IDirnodeURI)
-def from_string_filenode(s):
- u = from_string(s)
+def from_string_filenode(s, **kwargs):
+ u = from_string(s, **kwargs)
assert IFileURI.providedBy(u)
return u
registerAdapter(from_string_filenode, str, IFileURI)
-def from_string_mutable_filenode(s):
- u = from_string(s)
+def from_string_mutable_filenode(s, **kwargs):
+ u = from_string(s, **kwargs)
assert IMutableFileURI.providedBy(u)
return u
registerAdapter(from_string_mutable_filenode, str, IMutableFileURI)
-def from_string_verifier(s):
- u = from_string(s)
+def from_string_verifier(s, **kwargs):
+ u = from_string(s, **kwargs)
assert IVerifierURI.providedBy(u)
return u
registerAdapter(from_string_verifier, str, IVerifierURI)