Source code for invenio_previewer.extensions.simple_image

# -*- coding: utf-8 -*-
#
# This file is part of Invenio.
# Copyright (C) 2016-2019 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.

"""Previews simple image files."""

from __future__ import absolute_import, print_function

from flask import current_app, render_template

previewable_extensions = ['jpg', 'jpeg', 'png', 'gif']


def validate(file):
    """Validate a simple image file."""
    max_file_size = current_app.config.get(
        'PREVIEWER_MAX_IMAGE_SIZE_BYTES', 0.5 * 1024 * 1024)
    return file.size <= max_file_size


def can_preview(file):
    """Determine if the given file can be previewed."""
    supported_extensions = ('.jpg', '.jpeg', '.png', '.gif')
    return file.has_extensions(*supported_extensions) and validate(file)


def preview(file):
    """Render the appropriate template with embed flag."""
    return render_template(
        'invenio_previewer/simple_image.html',
        file=file,
        css_bundles=['simple_image_css.css'],
    )