Source code for invenio_previewer.extensions.csv_dthreejs
# -*- coding: utf-8 -*-
#
# This file is part of Invenio.
# Copyright (C) 2015-2019 CERN.
#
# Invenio is free software; you can redistribute it and/or modify it
# under the terms of the MIT License; see LICENSE file for more details.
"""Render a CSV file using d3.js."""
from __future__ import absolute_import, print_function
import csv
from flask import current_app, render_template
from ..proxies import current_previewer
from ..utils import detect_encoding
previewable_extensions = ['csv', 'dsv']
[docs]def validate_csv(file):
"""Return dialect information about given csv file."""
try:
# Detect encoding and dialect
with file.open() as fp:
encoding = detect_encoding(fp, default='utf-8')
sample = fp.read(
current_app.config.get('PREVIEWER_CSV_VALIDATION_BYTES', 1024))
allowed_delimiters = current_app.config.get(
'PREVIEWER_CSV_SNIFFER_ALLOWED_DELIMITERS', None)
delimiter = csv.Sniffer().sniff(
sample=sample.decode(encoding),
delimiters=allowed_delimiters).delimiter
is_valid = True
except Exception as e:
current_app.logger.debug(
'File {0} is not valid CSV: {1}'.format(file.uri, e))
encoding = ''
delimiter = ''
is_valid = False
return {
'delimiter': delimiter,
'encoding': encoding,
'is_valid': is_valid
}
[docs]def can_preview(file):
"""Determine if the given file can be previewed."""
if file.is_local() and file.has_extensions('.csv', '.dsv'):
return validate_csv(file)['is_valid']
return False
[docs]def preview(file):
"""Render the appropriate template with embed flag."""
file_info = validate_csv(file)
return render_template(
'invenio_previewer/csv_bar.html',
file=file,
delimiter=file_info['delimiter'],
encoding=file_info['encoding'],
js_bundles=current_previewer.js_bundles + ['d3_csv.js'],
css_bundles=current_previewer.css_bundles,
)