# This file is part of Sympathy for Data.
# Copyright (c) 2013, Combine Control Systems AB
#
# Sympathy for Data is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, version 3 of the License.
#
# Sympathy for Data is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with Sympathy for Data. If not, see <http://www.gnu.org/licenses/>.
import csv
from sympathy.api import qt2 as qt_compat
from sylib.export import table as exporttable
from sympathy.api import node as synode
QtGui = qt_compat.import_module('QtGui')
QtWidgets = qt_compat.import_module('QtWidgets')
# We are currently unable to support UTF-16 encodings since this plugin uses
# pythons csv module and from python docs
# (https://docs.python.org/2/library/csv.html#examples):
#
# The csv module doesn't directly support reading and writing Unicode, but
# it is 8-bit-clean save for some problems with ASCII NUL characters. So
# you can write functions or classes that handle the encoding and decoding
# for you as long as you avoid encodings like UTF-16 that use NULs. UTF-8
# is recommended.
#
# So if we ever want to support UTF-16 we would have to use a different
# backend.
CODEC_LANGS = dict((
('Western (ASCII)', 'ascii'),
('Western (ISO 8859-1)', 'iso8859_1'),
('Western (ISO 8859-15)', 'iso8859_15'),
('Western (Windows 1252)', 'windows-1252'),
('UTF-8', 'utf_8'),
('UTF-8 with signature byte', 'utf_8_sig')
))
def _pandas_to_csv(tabledata, fq_outfilename, header, encoding, delimiter,
quotechar):
tabledata.to_dataframe().to_csv(fq_outfilename,
sep=delimiter,
index=False,
quotechar=quotechar,
doublequote=True,
quoting=csv.QUOTE_MINIMAL,
encoding=encoding)
class DataExportCSVWidget(QtWidgets.QWidget):
filename_changed = qt_compat.Signal()
def __init__(self, parameter_root, *args, **kwargs):
super().__init__(*args, **kwargs)
self._parameter_root = parameter_root
self._init_gui()
def _init_gui(self):
table_names_gui = self._parameter_root['table_names'].gui()
table_names_gui.valueChanged.connect(self._filename_changed)
vlayout = QtWidgets.QVBoxLayout()
vlayout.addWidget(self._parameter_root['encoding'].gui())
vlayout.addWidget(table_names_gui)
vlayout.addWidget(self._parameter_root['header'].gui())
vlayout.addWidget(self._parameter_root['fast'].gui())
self.setLayout(vlayout)
def _filename_changed(self):
self.filename_changed.emit()
[docs]class DataExportCSV(exporttable.TableDataExporterBase):
"""Exporter for CSV files."""
EXPORTER_NAME = "CSV"
FILENAME_EXTENSION = "csv"
def __init__(self, parameters):
super().__init__(parameters)
if 'table_names' not in parameters:
parameters.set_boolean(
'table_names', label='Use table names as filenames',
description='Use table names as filenames')
if 'header' not in parameters:
parameters.set_boolean(
'header', value=True, label='Export header',
description='Export column names')
if 'encoding' not in parameters:
parameters.set_list(
'encoding', label='Character encoding',
list=CODEC_LANGS.keys(), value=[4],
description='Character encoding determines how different '
'characters are represented when written to disc, '
'sent over a network, etc.',
editor=synode.editors.combo_editor())
if 'fast' not in parameters:
parameters.set_boolean(
'fast', value=False, label='Use fast exporter',
description=('Fast exporter uses pandas and may produce '
'different results than the default one.'))
def parameter_view(self, node_context_input):
return DataExportCSVWidget(self._parameters)
def export_data(self, in_sytable, fq_outfilename, progress=None):
"""Export Table to CSV."""
header = self._parameters['header'].value
delimiter = ';'
quotechar = '"'
encoding = CODEC_LANGS[
self._parameters['encoding'].selected]
kwargs = {
'header': header, 'encoding': encoding,
'delimiter': delimiter, 'quotechar': quotechar}
if self._parameters['fast'].value:
_pandas_to_csv(in_sytable, fq_outfilename, **kwargs)
else:
in_sytable.to_csv(fq_outfilename, **kwargs)
