def generate_thumbnail(self):
"""Create thumbnail for resource request.
Raises:
ThumbnailPageNotFoundError: If resource with more than one page does
not provide a thumbnail page.
MoreThanOneThumbnailPageFoundError: If resource provides more than
one page as the thumbnail.
Returns:
Dictionary of thumbnail data.
"""
thumbnail_data = self.data()
if not isinstance(thumbnail_data, list):
thumbnail_data = [thumbnail_data]
if len(thumbnail_data) > 1:
thumbnail_data = list(
filter(lambda thumbnail_data: thumbnail_data.get("thumbnail"),
thumbnail_data))
if len(thumbnail_data) == 0:
raise ThumbnailPageNotFoundError(self)
elif len(thumbnail_data) > 1:
raise MoreThanOneThumbnailPageFoundError(self)
thumbnail_data = resize_encode_resource_images(
self.options["paper_size"].value, thumbnail_data)
return thumbnail_data[0]
def test_resize_encode_resource_images_image_letter_not_resized(self):
image = Image.new("1", (100, 100))
data = [{"type": "image", "data": image}]
copy = resize_encode_resource_images("letter", data)
copy_data = BytesIO(base64.b64decode(copy[0]["data"]))
copy_image = Image.open(copy_data)
self.assertEqual(image.size, copy_image.size)
def test_resize_encode_resource_images_image_letter_resized(self):
size = 3000
ratio = (self.LETTER_HEIGHT * self.MM_TO_PIXEL_RATIO) / size
expected_size = (int(size * ratio), int(size * ratio))
image = Image.new("1", (size, size))
data = [{"type": "image", "data": image}]
copy = resize_encode_resource_images("letter", data)
copy_data = BytesIO(base64.b64decode(copy[0]["data"]))
copy_image = Image.open(copy_data)
self.assertEqual(expected_size, copy_image.size)
def pdf(self, resource_name):
"""Return PDF for resource request.
The PDF is returned (compared to the thumbnail which is directly saved)
as the PDF may be either saved to the disk, or returned in a HTTP
response.
Args:
resource_name: Name of the resource (str).
Return:
PDF file of resource.
"""
# Only import weasyprint when required as production environment
# does not have it installed.
from weasyprint import HTML, CSS
context = dict()
context["resource"] = resource_name
context["header_text"] = self.options["header_text"].value
context["paper_size"] = self.options["paper_size"].value
if self.copies:
num_copies = self.options["copies"].value
else:
num_copies = 1
context["all_data"] = []
for copy in range(num_copies):
copy_data = self.data()
if not isinstance(copy_data, list):
copy_data = [copy_data]
copy_data = resize_encode_resource_images(
self.options["paper_size"].value,
copy_data
)
context["all_data"].append(copy_data)
filename = "{} ({})".format(resource_name, self.subtitle)
context["filename"] = filename
pdf_html = render_to_string("resources/base-resource-pdf.html", context)
html = HTML(string=pdf_html, base_url=settings.BUILD_ROOT)
css_file = finders.find("css/print-resource-pdf.css")
css_string = open(css_file, encoding="UTF-8").read()
base_css = CSS(string=css_string)
return (html.write_pdf(stylesheets=[base_css]), filename)
