Python CachingFilePath.moveTo方法代码示例

# 需要导入模块: from twext.python.filepath import CachingFilePath [as 别名]
# 或者: from twext.python.filepath.CachingFilePath import moveTo [as 别名]
class AttachmentStorageTransport(StorageTransportBase):

    _TEMPORARY_UPLOADS_DIRECTORY = "Temporary"

    def __init__(self, attachment, contentType, dispositionName, creating=False, migrating=False):
        super(AttachmentStorageTransport, self).__init__(
            attachment, contentType, dispositionName)

        fileDescriptor, fileName = self._temporaryFile()
        # Wrap the file descriptor in a file object we can write to
        self._file = os.fdopen(fileDescriptor, "w")
        self._path = CachingFilePath(fileName)
        self._hash = hashlib.md5()
        self._creating = creating
        self._migrating = migrating

        self._txn.postAbort(self.aborted)


    def _temporaryFile(self):
        """
        Returns a (file descriptor, absolute path) tuple for a temporary file within
        the Attachments/Temporary directory (creating the Temporary subdirectory
        if it doesn't exist).  It is the caller's responsibility to remove the
        file.
        """
        attachmentRoot = self._txn._store.attachmentsPath
        tempUploadsPath = attachmentRoot.child(self._TEMPORARY_UPLOADS_DIRECTORY)
        if not tempUploadsPath.exists():
            tempUploadsPath.createDirectory()
        return tempfile.mkstemp(dir=tempUploadsPath.path)


    @property
    def _txn(self):
        return self._attachment._txn


    def aborted(self):
        """
        Transaction aborted - clean up temp files.
        """
        if self._path.exists():
            self._path.remove()


    def write(self, data):
        if isinstance(data, buffer):
            data = str(data)
        self._file.write(data)
        self._hash.update(data)


    @inlineCallbacks
    def loseConnection(self):
        """
        Note that when self._migrating is set we only care about the data and don't need to
        do any quota checks/adjustments.
        """

        # FIXME: this should be synchronously accessible; IAttachment should
        # have a method for getting its parent just as CalendarObject/Calendar
        # do.

        # FIXME: If this method isn't called, the transaction should be
        # prevented from committing successfully.  It's not valid to have an
        # attachment that doesn't point to a real file.

        home = (yield self._txn.calendarHomeWithResourceID(self._attachment._ownerHomeID))

        oldSize = self._attachment.size()
        newSize = self._file.tell()
        self._file.close()

        # Check max size for attachment
        if not self._migrating and newSize > config.MaximumAttachmentSize:
            self._path.remove()
            if self._creating:
                yield self._attachment._internalRemove()
            raise AttachmentSizeTooLarge()

        # Check overall user quota
        if not self._migrating:
            allowed = home.quotaAllowedBytes()
            if allowed is not None and allowed < ((yield home.quotaUsedBytes())
                                                  + (newSize - oldSize)):
                self._path.remove()
                if self._creating:
                    yield self._attachment._internalRemove()
                raise QuotaExceeded()

        self._path.moveTo(self._attachment._path)

        yield self._attachment.changed(
            self._contentType,
            self._dispositionName,
            self._hash.hexdigest(),
            newSize
        )

#.........这里部分代码省略.........