コード例 #1
0
ファイル: convenience.py プロジェクト: coleb/PyFITS
def _get_file_mode(filename, default='copyonwrite'):
    """
    Allow file object to already be opened in any of the valid modes and
    and leave the file in the same state (opened or closed) as when
    the function was called.
    """

    mode = default
    closed = True

    if hasattr(filename, 'closed'):
        closed = filename.closed
    elif hasattr(filename, 'fileobj') and filename.fileobj is not None:
        closed = filename.fileobj.closed

    if (isfile(filename) or
        isinstance(filename, gzip.GzipFile) and not closed):
        if isinstance(filename, gzip.GzipFile):
            file_mode = filename.fileobj.mode
        else:
            file_mode = filename.mode

        for key, val in PYTHON_MODES.iteritems():
            if val == file_mode:
                mode = key
                break

    return mode, closed
コード例 #2
0
ファイル: file.py プロジェクト: theseusyang/scalrr-1
    def _open_fileobj(self, fileobj, mode):
        """Open a FITS file from a file object or a GzipFile object."""

        closed = fileobj_closed(fileobj)
        fmode = fileobj_mode(fileobj) or PYTHON_MODES[mode]

        if not closed:
            # In some cases (like on Python 3) a file opened for appending
            # still shows a mode of 'r+', hence the extra check for the append
            # case
            if ((mode == 'append' and fmode not in ('ab+', 'rb+')) or
                (mode != 'append' and PYTHON_MODES[mode] != fmode)):
                raise ValueError(
                    "Input mode '%s' (%s) does not match mode of the "
                    "input file (%s)." % (mode, PYTHON_MODES[mode], fmode))
            self.__file = fileobj
        elif isfile(fileobj):
            self.__file = fileobj_open(self.name, PYTHON_MODES[mode])
            # Return to the beginning of the file--in Python 3 when opening in
            # append mode the file pointer is at the end of the file
            self.__file.seek(0)
        else:
            self.__file = gzip.open(self.name, PYTHON_MODES[mode])
コード例 #3
0
ファイル: hdulist.py プロジェクト: theseusyang/scalrr-1
    def writeto(self, fileobj, output_verify='exception', clobber=False,
                checksum=False):
        """
        Write the `HDUList` to a new file.

        Parameters
        ----------
        fileobj : file path, file object or file-like object
            File to write to.  If a file object, must be opened for
            append (ab+).

        output_verify : str
            Output verification option.  Must be one of ``"fix"``,
            ``"silentfix"``, ``"ignore"``, ``"warn"``, or
            ``"exception"``.  See :ref:`verify` for more info.

        clobber : bool
            When `True`, overwrite the output file if exists.

        checksum : bool
            When `True` adds both ``DATASUM`` and ``CHECKSUM`` cards
            to the headers of all HDU's written to the file.
        """

        if (len(self) == 0):
            warnings.warn("There is nothing to write.")
            return

        self.verify(option=output_verify)

        # check if the file object is closed
        closed = fileobj_closed(fileobj)
        fmode = fileobj_mode(fileobj) or 'ab+'
        filename = fileobj_name(fileobj)

        # check if the output file already exists
        if (isfile(fileobj) or
            isinstance(fileobj, (basestring, gzip.GzipFile))):
            if (os.path.exists(filename) and os.path.getsize(filename) != 0):
                if clobber:
                    warnings.warn("Overwriting existing file '%s'." % filename)
                    if not closed:
                        fileobj.close()
                    os.remove(filename)
                else:
                    raise IOError("File '%s' already exists." % filename)
        elif (hasattr(fileobj, 'len') and fileobj.len > 0):
            if clobber:
                warnings.warn("Overwriting existing file '%s'." % filename)
                name.truncate(0)
            else:
                raise IOError("File '%s' already exists." % filename)

        # make sure the EXTEND keyword is there if there is extension
        self.update_extend()

        mode = 'copyonwrite'
        for key, val in PYTHON_MODES.iteritems():
            if val == fmode:
                mode = key
                break

        hdulist = fitsopen(fileobj, mode=mode)

        for hdu in self:
            hdu._prewriteto(checksum=checksum)
            try:
                hdu._writeto(hdulist.__file)
            finally:
                hdu._postwriteto()
        hdulist.close(output_verify=output_verify, closed=closed)
コード例 #4
0
ファイル: file.py プロジェクト: pombredanne/PyFITS
    def __init__(self, fileobj=None, mode='readonly', memmap=False):
        if fileobj is None:
            self.__file = None
            self.closed = False
            self.mode = mode
            self.memmap = memmap
            self.compression = None
            self.readonly = False
            self.writeonly = False
            self.simulateonly = True
            return
        else:
            self.simulateonly = False

        if mode not in PYTHON_MODES:
            raise ValueError("Mode '%s' not recognized" % mode)

        if (isinstance(fileobj, basestring) and mode != 'append' and
            not os.path.exists(fileobj) and
            not os.path.splitdrive(fileobj)[0]):
                #
                # Not writing file and file does not exist on local machine and
                # name does not begin with a drive letter (Windows), try to
                # get it over the web.
                #
            self.name, _ = urllib.urlretrieve(fileobj)
        else:
            self.name = fileobj_name(fileobj)

        self.closed = False
        self.mode = mode
        self.memmap = memmap

        # Underlying fileobj is a file-like object, but an actual file object
        self.file_like = False

        # More defaults to be adjusted below as necessary
        self.compression = None
        self.readonly = False
        self.writeonly = False

        # Initialize the internal self.__file object
        if isfile(fileobj) or isinstance(fileobj, gzip.GzipFile):
            closed = fileobj_closed(fileobj)
            fmode = fileobj_mode(fileobj) or PYTHON_MODES[mode]

            if not closed:
                # In some cases (like on Python 3) a file opened for
                # appending still shows a mode of 'r+', hence the extra
                # check for the append case
                if ((mode == 'append' and fmode not in ('ab+', 'rb+')) or
                    (mode != 'append' and PYTHON_MODES[mode] != fmode)):
                    raise ValueError(
                        "Input mode '%s' (%s) does not match mode of the "
                        "input file (%s)." % (mode, PYTHON_MODES[mode], fmode))
                self.__file = fileobj
            elif isfile(fileobj):
                self.__file = fileobj_open(self.name, PYTHON_MODES[mode])
                # Return to the beginning of the file--in Python 3 when
                # opening in append mode the file pointer is at the end of
                # the file
                self.__file.seek(0)
            else:
                self.__file = gzip.open(self.name, PYTHON_MODES[mode])
        elif isinstance(fileobj, basestring):
            if os.path.exists(self.name):
                with fileobj_open(self.name, 'rb') as f:
                    magic = f.read(4)
            else:
                magic = ''.encode('raw-unicode-escape')
            ext = os.path.splitext(self.name)[1]
            if ext == '.gz' or magic.startswith(GZIP_MAGIC):
                # Handle gzip files
                if mode in ['update', 'append']:
                    raise IOError(
                          "Writing to gzipped fits files is not currently "
                          "supported")
                self.__file = gzip.open(self.name)
                self.compression = 'gzip'
            elif ext == '.zip' or magic.startswith(PKZIP_MAGIC):
                # Handle zip files
                if mode in ['update', 'append']:
                    raise IOError(
                          "Writing to zipped fits files is not currently "
                          "supported")
                zfile = zipfile.ZipFile(self.name)
                namelist = zfile.namelist()
                if len(namelist) != 1:
                    raise IOError(
                      "Zip files with multiple members are not supported.")
                self.__file = tempfile.NamedTemporaryFile(suffix='.fits')
                self.__file.write(zfile.read(namelist[0]))
                zfile.close()
                self.compression = 'zip'
            else:
                self.__file = fileobj_open(self.name, PYTHON_MODES[mode])
                # Make certain we're back at the beginning of the file
            self.__file.seek(0)
        else:
            # We are dealing with a file like object.
            # Assume it is open.
            self.file_like = True
            self.__file = fileobj

            # If there is not seek or tell methods then set the mode to
            # output streaming.
            if (not hasattr(self.__file, 'seek') or
                not hasattr(self.__file, 'tell')):
                self.mode = mode = 'ostream'

            if (self.mode in ('copyonwrite', 'update', 'append') and
                not hasattr(self.__file, 'write')):
                raise IOError("File-like object does not have a 'write' "
                              "method, required for mode '%s'."
                              % self.mode)

            if (self.mode in ('readonly', 'denywrite') and
                not hasattr(self.__file, 'read')):
                raise IOError("File-like object does not have a 'read' "
                              "method, required for mode %r."
                              % self.mode)

        if isinstance(fileobj, gzip.GzipFile):
            self.compression = 'gzip'
        elif isinstance(fileobj, zipfile.ZipFile):
            # Reading from zip files is supported but not writing (yet)
            self.compression = 'zip'

        if (mode in ('readonly', 'copyonwrite', 'denywrite') or
                (self.compression and mode == 'update')):
            self.readonly = True
        elif (mode == 'ostream' or
                (self.compression and mode == 'append')):
            self.writeonly = True

        # For 'ab+' mode, the pointer is at the end after the open in
        # Linux, but is at the beginning in Solaris.
        if (mode == 'ostream' or self.compression or
            not hasattr(self.__file, 'seek')):
            # For output stream start with a truncated file.
            # For compressed files we can't really guess at the size
            self.size = 0
        else:
            pos = self.__file.tell()
            self.__file.seek(0, 2)
            self.size = self.__file.tell()
            self.__file.seek(pos)

        if self.memmap and not isfile(self.__file):
            self.memmap = False
コード例 #5
0
ファイル: file.py プロジェクト: theseusyang/scalrr-1
    def __init__(self, fileobj=None, mode='readonly', memmap=False):
        if fileobj is None:
            self.__file = None
            self.closed = False
            self.mode = mode
            self.memmap = memmap
            self.compression = None
            self.readonly = False
            self.writeonly = False
            self.simulateonly = True
            return
        else:
            self.simulateonly = False

        if mode not in PYTHON_MODES:
            raise ValueError("Mode '%s' not recognized" % mode)

        if (isinstance(fileobj, basestring) and mode != 'append' and
            not os.path.exists(fileobj) and
            not os.path.splitdrive(fileobj)[0]):
                #
                # Not writing file and file does not exist on local machine and
                # name does not begin with a drive letter (Windows), try to
                # get it over the web.
                #
            try:
                self.name, _ = urllib.urlretrieve(fileobj)
            except (TypeError, ValueError):
                # A couple different exceptions can occur here when passing a
                # filename into urlretrieve in Python 3
                raise IOError('File does not exist: %r' % fileobj)
        else:
            self.name = fileobj_name(fileobj)

        self.closed = False
        self.mode = mode
        self.memmap = memmap

        # Underlying fileobj is a file-like object, but an actual file object
        self.file_like = False

        # More defaults to be adjusted below as necessary
        self.compression = None
        self.readonly = False
        self.writeonly = False

        # Initialize the internal self.__file object
        if isfile(fileobj) or isinstance(fileobj, gzip.GzipFile):
            self._open_fileobj(fileobj, mode)
        elif isinstance(fileobj, basestring):
            self._open_filename(fileobj, mode)
        else:
            self._open_filelike(fileobj, mode)

        if isinstance(fileobj, gzip.GzipFile):
            self.compression = 'gzip'
        elif isinstance(fileobj, zipfile.ZipFile):
            # Reading from zip files is supported but not writing (yet)
            self.compression = 'zip'

        if (mode in ('readonly', 'copyonwrite', 'denywrite') or
                (self.compression and mode == 'update')):
            self.readonly = True
        elif (mode == 'ostream' or
                (self.compression and mode == 'append')):
            self.writeonly = True

        # For 'ab+' mode, the pointer is at the end after the open in
        # Linux, but is at the beginning in Solaris.
        if (mode == 'ostream' or self.compression or
            not hasattr(self.__file, 'seek')):
            # For output stream start with a truncated file.
            # For compressed files we can't really guess at the size
            self.size = 0
        else:
            pos = self.__file.tell()
            self.__file.seek(0, 2)
            self.size = self.__file.tell()
            self.__file.seek(pos)

        if self.memmap and not isfile(self.__file):
            self.memmap = False