Cura/plugins/GCodeGzWriter/GCodeGzWriter.py

# Copyright (c) 2018 Ultimaker B.V.
# Cura is released under the terms of the LGPLv3 or higher.

import gzip
from io import StringIO, BufferedIOBase #To write the g-code to a temporary buffer, and for typing.
from typing import cast, List

from UM.Logger import Logger
from UM.Mesh.MeshWriter import MeshWriter #The class we're extending/implementing.
from UM.PluginRegistry import PluginRegistry
from UM.Scene.SceneNode import SceneNode #For typing.

from UM.i18n import i18nCatalog
catalog = i18nCatalog("cura")


class GCodeGzWriter(MeshWriter):
    """A file writer that writes gzipped g-code.

    If you're zipping g-code, you might as well use gzip!
    """


    def __init__(self) -> None:
        super().__init__(add_to_recent_files = False)

    def write(self, stream: BufferedIOBase, nodes: List[SceneNode], mode = MeshWriter.OutputMode.BinaryMode) -> bool:
        """Writes the gzipped g-code to a stream.

        Note that even though the function accepts a collection of nodes, the
        entire scene is always written to the file since it is not possible to
        separate the g-code for just specific nodes.

        :param stream: The stream to write the gzipped g-code to.
        :param nodes: This is ignored.
        :param mode: Additional information on what type of stream to use. This
            must always be binary mode.
        :return: Whether the write was successful.
        """

        if mode != MeshWriter.OutputMode.BinaryMode:
            Logger.log("e", "GCodeGzWriter does not support text mode.")
            self.setInformation(catalog.i18nc("@error:not supported", "GCodeGzWriter does not support text mode."))
            return False

        #Get the g-code from the g-code writer.
        gcode_textio = StringIO() #We have to convert the g-code into bytes.
        gcode_writer = cast(MeshWriter, PluginRegistry.getInstance().getPluginObject("GCodeWriter"))
        success = gcode_writer.write(gcode_textio, None)
        if not success: #Writing the g-code failed. Then I can also not write the gzipped g-code.
            self.setInformation(gcode_writer.getInformation())
            return False

        result = gzip.compress(gcode_textio.getvalue().encode("utf-8"))
        stream.write(result)
        return True