changeset 2501:3b67fe672206

core (memory): file metadata handling methods: - checkFilePermission check that requested permission(s) are granted for a file (without checking the parents) - checkPermissionToRoot check that requested permission(s) are granted for a file and all its parents - getFiles retrieve file(s) according to filter, and check permissions by default - setFile create a file (and its parents if needed) and check permissions by default
author Goffi <goffi@goffi.org>
date Wed, 28 Feb 2018 18:28:39 +0100 (2018-02-28)
parents 898b6e1fdc7a
children 7ad5f2c4e34a
files src/memory/memory.py
diffstat 1 files changed, 242 insertions(+), 0 deletions(-) [+]
line wrap: on
line diff
--- a/src/memory/memory.py	Wed Feb 28 18:28:39 2018 +0100
+++ b/src/memory/memory.py	Wed Feb 28 18:28:39 2018 +0100
@@ -39,6 +39,9 @@
 from sat.memory.crypto import BlockCipher
 from sat.memory.crypto import PasswordHasher
 from sat.tools import config as tools_config
+import shortuuid
+import mimetypes
+import time
 
 
 PresenceTuple = namedtuple("PresenceTuple", ('show', 'priority', 'statuses'))
@@ -1058,6 +1061,245 @@
     def setDefault(self, name, category, callback, errback=None):
         return self.params.setDefault(name, category, callback, errback)
 
+    ## Files ##
+
+    def checkFilePermission(self, file_data, peer_jid, perms_to_check):
+        """check that an entity has the right permission on a file
+
+        @param file_data(dict): data of one file, as returned by getFiles
+        @param peer_jid(jid.JID): entity trying to access the file
+        @param perms_to_check(tuple[unicode]): permissions to check
+            tuple of C.ACCESS_PERM_*
+        @param check_parents(bool): if True, also check all parents until root node
+        @raise exceptions.PermissionError: peer_jid doesn't have all permission
+            in perms_to_check for file_data
+        @raise exceptions.InternalError: perms_to_check is invalid
+        """
+        if peer_jid is None and perms_to_check is None:
+            return
+        peer_jid = peer_jid.userhostJID()
+        if peer_jid == file_data['owner']:
+            # the owner has all rights
+            return
+        if not C.ACCESS_PERMS.issuperset(perms_to_check):
+            raise exceptions.InternalError(_(u'invalid permission'))
+
+        for perm in perms_to_check:
+            # we check each perm and raise PermissionError as soon as one condition is not valid
+            # we must never return here, we only return after the loop if nothing was blocking the access
+            try:
+                perm_data = file_data[u'access'][perm]
+                perm_type = perm_data[u'type']
+            except KeyError:
+                raise failure.Failure(exceptions.PermissionError())
+            if perm_type == C.ACCESS_TYPE_PUBLIC:
+                continue
+            elif perm_type == C.ACCESS_TYPE_WHITELIST:
+                try:
+                    jids = perm_data[u'jids']
+                except KeyError:
+                    raise failure.Failure(exceptions.PermissionError())
+                if peer_jid.full() in jids:
+                    continue
+                else:
+                    raise failure.Failure(exceptions.PermissionError())
+            else:
+                raise exceptions.InternalError(_(u'unknown access type: {type}').format(type=perm_type))
+
+    @defer.inlineCallbacks
+    def checkPermissionToRoot(self, client, file_data, peer_jid, perms_to_check):
+        """do checkFilePermission on file_data and all its parents until root"""
+        current = file_data
+        while True:
+            self.checkFilePermission(current, peer_jid, perms_to_check)
+            parent = current[u'parent']
+            if not parent:
+                break
+            files_data = yield self.getFile(self, client, peer_jid=None, file_id=parent, perms_to_check=None)
+            try:
+                current = files_data[0]
+            except IndexError:
+                raise exceptions.DataError(u'Missing parent')
+
+    @defer.inlineCallbacks
+    def _getParentDir(self, client, path, parent, namespace, owner, peer_jid, perms_to_check):
+        """Retrieve parent node from a path, or last existing directory
+
+        each directory of the path will be retrieved, until the last existing one
+        @return (tuple[unicode, list[unicode])): parent, remaining path elements:
+            - parent is the id of the last retrieved directory (or u'' for root)
+            - remaining path elements are the directories which have not been retrieved
+              (i.e. which don't exist)
+        """
+        # if path is set, we have to retrieve parent directory of the file(s) from it
+        if parent is not None:
+            raise exceptions.ConflictError(_(u"You can't use path and parent at the same time"))
+        path_elts = filter(None, path.split(u'/'))
+        if {u'..', u'.'}.intersection(path_elts):
+            raise ValueError(_(u'".." or "." can\'t be used in path'))
+
+        # we retrieve all directories from path until we get the parent container
+        # non existing directories will be created
+        parent = u''
+        for idx, path_elt in enumerate(path_elts):
+            directories = yield self.storage.getFiles(client, parent=parent, type_=C.FILE_TYPE_DIRECTORY,
+                                                      name=path_elt, namespace=namespace, owner=owner)
+            if not directories:
+                defer.returnValue((parent, path_elts[idx:]))
+                # from this point, directories don't exist anymore, we have to create them
+            elif len(directories) > 1:
+                raise exceptions.InternalError(_(u"Several directories found, this should not happen"))
+            else:
+                directory = directories[0]
+                self.checkFilePermission(directory, peer_jid, perms_to_check)
+                parent = directory[u'id']
+        defer.returnValue((parent, []))
+
+    @defer.inlineCallbacks
+    def getFiles(self, client, peer_jid, file_id=None, version=None, parent=None, path=None, type_=None,
+                 file_hash=None, hash_algo=None, name=None, namespace=None, mime_type=None,
+                 owner=None, access=None, projection=None, unique=False, perms_to_check=(C.ACCESS_PERM_READ,)):
+        """retrieve files with with given filters
+
+        @param peer_jid(jid.JID, None): jid trying to access the file
+            needed to check permission.
+            Use None to ignore permission (perms_to_check must be None too)
+        @param file_id(unicode, None): id of the file
+            None to ignore
+        @param version(unicode, None): version of the file
+            None to ignore
+            empty string to look for current version
+        @param parent(unicode, None): id of the directory containing the files
+            None to ignore
+            empty string to look for root files/directories
+        @param projection(list[unicode], None): name of columns to retrieve
+            None to retrieve all
+        @param unique(bool): if True will remove duplicates
+        @param perms_to_check(tuple[unicode],None): permission to check
+            must be a tuple of C.ACCESS_PERM_* or None
+            if None, permission will no be checked (peer_jid must be None too in this case)
+        other params are the same as for [setFile]
+        @return (list[dict]): files corresponding to filters
+        @raise exceptions.NotFound: parent directory not found (when path is specified)
+        @raise exceptions.PermissionError: peer_jid can't use perms_to_check for one of the file
+            on the path
+        """
+        if peer_jid is None and perms_to_check or perms_to_check is None and peer_jid:
+            raise exceptions.InternalError('if you want to disable permission check, both peer_jid and perms_to_check must be None')
+        if path is not None:
+            # permission are checked by _getParentDir
+            parent, remaining_path_elts = yield self._getParentDir(client, path, parent, namespace, owner, peer_jid, perms_to_check)
+            if remaining_path_elts:
+                # if we have remaining path elements,
+                # the parent directory is not found
+                raise failure.Failure(exceptions.NotFound())
+        if parent and peer_jid:
+            # if parent is given directly and permission check is need,
+            # we need to check all the parents
+            parent_data = yield self.storage.getFiles(client, file_id=parent)
+            try:
+                parent_data = parent_data[0]
+            except IndexError:
+                raise exceptions.DataError(u'mising parent')
+            yield self.checkPermissionToRoot(client, parent_data, peer_jid, perms_to_check)
+
+        files = yield self.storage.getFiles(client, file_id=file_id, version=version, parent=parent, type_=type_,
+                                            file_hash=file_hash, hash_algo=hash_algo, name=name, namespace=namespace,
+                                            mime_type=mime_type, owner=owner, access=access,
+                                            projection=projection, unique=unique)
+
+        if peer_jid:
+            # if permission are checked, we must remove all file tha use can't access
+            to_remove = []
+            for file_data in files:
+                try:
+                    self.checkFilePermission(file_data, peer_jid, perms_to_check)
+                except exceptions.PermissionError:
+                    to_remove.append(file_data)
+            for file_data in to_remove:
+                files.remove(file_data)
+        defer.returnValue(files)
+
+    @defer.inlineCallbacks
+    def setFile(self, client, name, file_id=None, version=u'', parent=None, path=None,
+                type_=C.FILE_TYPE_FILE, file_hash=None, hash_algo=None, size=None, namespace=None,
+                mime_type=None, created=None, modified=None, owner=None, access=None, extra=None,
+                peer_jid = None, perms_to_check=(C.ACCESS_PERM_WRITE,)):
+        """set a file metadata
+
+        @param name(unicode): basename of the file
+        @param file_id(unicode): unique id of the file
+        @param version(unicode): version of this file
+            empty string for current version or when there is no versioning
+        @param parent(unicode, None): id of the directory containing the files
+        @param path(unicode, None): virtual path of the file in the namespace
+            if set, parent must be None. All intermediate directories will be created if needed,
+            using current access.
+        @param file_hash(unicode): unique hash of the payload
+        @param hash_algo(unicode): algorithm used for hashing the file (usually sha-256)
+        @param size(int): size in bytes
+        @param namespace(unicode, None): identifier (human readable is better) to group files
+            for instance, namespace could be used to group files in a specific photo album
+        @param mime_type(unicode): MIME type of the file, or None if not known/guessed
+        @param created(int): UNIX time of creation
+        @param modified(int,None): UNIX time of last modification, or None to use created date
+        @param owner(jid.JID, None): jid of the owner of the file (mainly useful for component)
+            will be used to check permission.
+            Use None to ignore permission (perms_to_check must be None too)
+        @param access(dict, None): serialisable dictionary with access rules.
+            None (or empty dict) to use private access, i.e. allow only profile's jid to access the file
+            key can be on on C.ACCESS_PERM_*,
+            then a sub dictionary with a type key is used (one of C.ACCESS_TYPE_*).
+            According to type, extra keys can be used:
+                - C.ACCESS_TYPE_PUBLIC: the permission is granted for everybody
+                - C.ACCESS_TYPE_WHITELIST: the permission is granted for jids (as unicode) in the 'jids' key
+            will be encoded to json in database
+        @param extra(dict, None): serialisable dictionary of any extra data
+            will be encoded to json in database
+        @param perms_to_check(tuple[unicode],None): permission to check
+            must be a tuple of C.ACCESS_PERM_* or None
+            if None, permission will no be checked (peer_jid must be None too in this case)
+        @param profile(unicode): profile owning the file
+        """
+        if '/' in name:
+            raise ValueError('name must not contain a slash ("/")')
+        if file_id is None:
+            file_id = shortuuid.uuid()
+        if file_hash is not None and hash_algo is None or hash_algo is not None and file_hash is None:
+            raise ValueError('file_hash and hash_algo must be set at the same time')
+        if mime_type is None:
+            mime_type, file_encoding = mimetypes.guess_type(name)
+        if created is None:
+            created = time.time()
+        if namespace is not None:
+            namespace = namespace.strip() or None
+        if type_ == C.FILE_TYPE_DIRECTORY:
+            if any(version, file_hash, size,  mime_type):
+                raise ValueError(u"version, file_hash, size and mime_type can't be set for a directory")
+
+        if path is not None:
+            if peer_jid is None:
+                peer_jid = owner
+            # _getParentDir will check permissions if peer_jid is set
+            parent, remaining_path_elts = self._getParentDir(client, path, parent, namespace, owner, owner, perms_to_check)
+            # if remaining directories don't exist, we have to create them
+            for new_dir in remaining_path_elts:
+                new_dir_id = shortuuid.uuid()
+                yield self.storage.setFile(client, name=new_dir, file_id=new_dir_id, version=u'', parent=parent,
+                                           type_=C.FILE_TYPE_DIRECTORY, namespace=namespace,
+                                           created=time.time(),
+                                           owner=owner.userhostJID() if owner else None,
+                                           access=access, extra={})
+                parent = new_dir_id
+        elif parent is None:
+            parent = u''
+
+        yield self.storage.setFile(client, file_id=file_id, version=version, parent=parent, type_=type_,
+                                   file_hash=file_hash, hash_algo=hash_algo, name=name, size=size,
+                                   namespace=namespace, mime_type=mime_type, created=created, modified=modified,
+                                   owner=owner.userhostJID() if owner else None,
+                                   access=access, extra=extra)
+
     ## Misc ##
 
     def isEntityAvailable(self, entity_jid, profile_key):