From b312769c0ee2c40b1a26a6ed39ea1c8a462d4349 Mon Sep 17 00:00:00 2001 From: Patrick Cloke Date: Wed, 9 Sep 2020 12:59:41 -0400 Subject: Do not error when thumbnailing invalid files (#8236) If a file cannot be thumbnailed for some reason (e.g. the file is empty), then catch the exception and convert it to a reasonable error message for the client. --- synapse/rest/media/v1/media_repository.py | 69 +++++++++++++++++++++++++---- synapse/rest/media/v1/thumbnail_resource.py | 5 ++- synapse/rest/media/v1/thumbnailer.py | 14 +++++- 3 files changed, 76 insertions(+), 12 deletions(-) (limited to 'synapse/rest/media') diff --git a/synapse/rest/media/v1/media_repository.py b/synapse/rest/media/v1/media_repository.py index 9a1b7779f7..69f353d46f 100644 --- a/synapse/rest/media/v1/media_repository.py +++ b/synapse/rest/media/v1/media_repository.py @@ -53,7 +53,7 @@ from .media_storage import MediaStorage from .preview_url_resource import PreviewUrlResource from .storage_provider import StorageProviderWrapper from .thumbnail_resource import ThumbnailResource -from .thumbnailer import Thumbnailer +from .thumbnailer import Thumbnailer, ThumbnailError from .upload_resource import UploadResource logger = logging.getLogger(__name__) @@ -460,13 +460,30 @@ class MediaRepository: return t_byte_source async def generate_local_exact_thumbnail( - self, media_id, t_width, t_height, t_method, t_type, url_cache - ): + self, + media_id: str, + t_width: int, + t_height: int, + t_method: str, + t_type: str, + url_cache: str, + ) -> Optional[str]: input_path = await self.media_storage.ensure_media_is_in_local_cache( FileInfo(None, media_id, url_cache=url_cache) ) - thumbnailer = Thumbnailer(input_path) + try: + thumbnailer = Thumbnailer(input_path) + except ThumbnailError as e: + logger.warning( + "Unable to generate a thumbnail for local media %s using a method of %s and type of %s: %s", + media_id, + t_method, + t_type, + e, + ) + return None + t_byte_source = await defer_to_thread( self.hs.get_reactor(), self._generate_thumbnail, @@ -506,14 +523,36 @@ class MediaRepository: return output_path + # Could not generate thumbnail. + return None + async def generate_remote_exact_thumbnail( - self, server_name, file_id, media_id, t_width, t_height, t_method, t_type - ): + self, + server_name: str, + file_id: str, + media_id: str, + t_width: int, + t_height: int, + t_method: str, + t_type: str, + ) -> Optional[str]: input_path = await self.media_storage.ensure_media_is_in_local_cache( FileInfo(server_name, file_id, url_cache=False) ) - thumbnailer = Thumbnailer(input_path) + try: + thumbnailer = Thumbnailer(input_path) + except ThumbnailError as e: + logger.warning( + "Unable to generate a thumbnail for remote media %s from %s using a method of %s and type of %s: %s", + media_id, + server_name, + t_method, + t_type, + e, + ) + return None + t_byte_source = await defer_to_thread( self.hs.get_reactor(), self._generate_thumbnail, @@ -559,6 +598,9 @@ class MediaRepository: return output_path + # Could not generate thumbnail. + return None + async def _generate_thumbnails( self, server_name: Optional[str], @@ -590,7 +632,18 @@ class MediaRepository: FileInfo(server_name, file_id, url_cache=url_cache) ) - thumbnailer = Thumbnailer(input_path) + try: + thumbnailer = Thumbnailer(input_path) + except ThumbnailError as e: + logger.warning( + "Unable to generate thumbnails for remote media %s from %s using a method of %s and type of %s: %s", + media_id, + server_name, + media_type, + e, + ) + return None + m_width = thumbnailer.width m_height = thumbnailer.height diff --git a/synapse/rest/media/v1/thumbnail_resource.py b/synapse/rest/media/v1/thumbnail_resource.py index a83535b97b..30421b663a 100644 --- a/synapse/rest/media/v1/thumbnail_resource.py +++ b/synapse/rest/media/v1/thumbnail_resource.py @@ -16,6 +16,7 @@ import logging +from synapse.api.errors import SynapseError from synapse.http.server import DirectServeJsonResource, set_cors_headers from synapse.http.servlet import parse_integer, parse_string @@ -173,7 +174,7 @@ class ThumbnailResource(DirectServeJsonResource): await respond_with_file(request, desired_type, file_path) else: logger.warning("Failed to generate thumbnail") - respond_404(request) + raise SynapseError(400, "Failed to generate thumbnail.") async def _select_or_generate_remote_thumbnail( self, @@ -235,7 +236,7 @@ class ThumbnailResource(DirectServeJsonResource): await respond_with_file(request, desired_type, file_path) else: logger.warning("Failed to generate thumbnail") - respond_404(request) + raise SynapseError(400, "Failed to generate thumbnail.") async def _respond_remote_thumbnail( self, request, server_name, media_id, width, height, method, m_type diff --git a/synapse/rest/media/v1/thumbnailer.py b/synapse/rest/media/v1/thumbnailer.py index d681bf7bf0..457ad6031c 100644 --- a/synapse/rest/media/v1/thumbnailer.py +++ b/synapse/rest/media/v1/thumbnailer.py @@ -15,7 +15,7 @@ import logging from io import BytesIO -from PIL import Image as Image +from PIL import Image logger = logging.getLogger(__name__) @@ -31,12 +31,22 @@ EXIF_TRANSPOSE_MAPPINGS = { } +class ThumbnailError(Exception): + """An error occurred generating a thumbnail.""" + + class Thumbnailer: FORMATS = {"image/jpeg": "JPEG", "image/png": "PNG"} def __init__(self, input_path): - self.image = Image.open(input_path) + try: + self.image = Image.open(input_path) + except OSError as e: + # If an error occurs opening the image, a thumbnail won't be able to + # be generated. + raise ThumbnailError from e + self.width, self.height = self.image.size self.transpose_method = None try: -- cgit 1.4.1