diff options
Diffstat (limited to 'synapse/media/thumbnailer.py')
| -rw-r--r-- | synapse/media/thumbnailer.py | 486 |
1 files changed, 485 insertions, 1 deletions
diff --git a/synapse/media/thumbnailer.py b/synapse/media/thumbnailer.py index 5538020bec..cc3acf51e1 100644 --- a/synapse/media/thumbnailer.py +++ b/synapse/media/thumbnailer.py @@ -22,11 +22,27 @@ import logging from io import BytesIO from types import TracebackType -from typing import Optional, Tuple, Type +from typing import TYPE_CHECKING, List, Optional, Tuple, Type from PIL import Image +from synapse.api.errors import Codes, SynapseError, cs_error +from synapse.config.repository import THUMBNAIL_SUPPORTED_MEDIA_FORMAT_MAP +from synapse.http.server import respond_with_json +from synapse.http.site import SynapseRequest from synapse.logging.opentracing import trace +from synapse.media._base import ( + FileInfo, + ThumbnailInfo, + respond_404, + respond_with_file, + respond_with_responder, +) +from synapse.media.media_storage import MediaStorage + +if TYPE_CHECKING: + from synapse.media.media_repository import MediaRepository + from synapse.server import HomeServer logger = logging.getLogger(__name__) @@ -231,3 +247,471 @@ class Thumbnailer: def __del__(self) -> None: # Make sure we actually do close the image, rather than leak data. self.close() + + +class ThumbnailProvider: + def __init__( + self, + hs: "HomeServer", + media_repo: "MediaRepository", + media_storage: MediaStorage, + ): + self.hs = hs + self.media_repo = media_repo + self.media_storage = media_storage + self.store = hs.get_datastores().main + self.dynamic_thumbnails = hs.config.media.dynamic_thumbnails + + async def respond_local_thumbnail( + self, + request: SynapseRequest, + media_id: str, + width: int, + height: int, + method: str, + m_type: str, + max_timeout_ms: int, + ) -> None: + media_info = await self.media_repo.get_local_media_info( + request, media_id, max_timeout_ms + ) + if not media_info: + return + + thumbnail_infos = await self.store.get_local_media_thumbnails(media_id) + await self._select_and_respond_with_thumbnail( + request, + width, + height, + method, + m_type, + thumbnail_infos, + media_id, + media_id, + url_cache=bool(media_info.url_cache), + server_name=None, + ) + + async def select_or_generate_local_thumbnail( + self, + request: SynapseRequest, + media_id: str, + desired_width: int, + desired_height: int, + desired_method: str, + desired_type: str, + max_timeout_ms: int, + ) -> None: + media_info = await self.media_repo.get_local_media_info( + request, media_id, max_timeout_ms + ) + + if not media_info: + return + + thumbnail_infos = await self.store.get_local_media_thumbnails(media_id) + for info in thumbnail_infos: + t_w = info.width == desired_width + t_h = info.height == desired_height + t_method = info.method == desired_method + t_type = info.type == desired_type + + if t_w and t_h and t_method and t_type: + file_info = FileInfo( + server_name=None, + file_id=media_id, + url_cache=bool(media_info.url_cache), + thumbnail=info, + ) + + responder = await self.media_storage.fetch_media(file_info) + if responder: + await respond_with_responder( + request, responder, info.type, info.length + ) + return + + logger.debug("We don't have a thumbnail of that size. Generating") + + # Okay, so we generate one. + file_path = await self.media_repo.generate_local_exact_thumbnail( + media_id, + desired_width, + desired_height, + desired_method, + desired_type, + url_cache=bool(media_info.url_cache), + ) + + if file_path: + await respond_with_file(request, desired_type, file_path) + else: + logger.warning("Failed to generate thumbnail") + raise SynapseError(400, "Failed to generate thumbnail.") + + async def select_or_generate_remote_thumbnail( + self, + request: SynapseRequest, + server_name: str, + media_id: str, + desired_width: int, + desired_height: int, + desired_method: str, + desired_type: str, + max_timeout_ms: int, + ) -> None: + media_info = await self.media_repo.get_remote_media_info( + server_name, media_id, max_timeout_ms + ) + if not media_info: + respond_404(request) + return + + thumbnail_infos = await self.store.get_remote_media_thumbnails( + server_name, media_id + ) + + file_id = media_info.filesystem_id + + for info in thumbnail_infos: + t_w = info.width == desired_width + t_h = info.height == desired_height + t_method = info.method == desired_method + t_type = info.type == desired_type + + if t_w and t_h and t_method and t_type: + file_info = FileInfo( + server_name=server_name, + file_id=file_id, + thumbnail=info, + ) + + responder = await self.media_storage.fetch_media(file_info) + if responder: + await respond_with_responder( + request, responder, info.type, info.length + ) + return + + logger.debug("We don't have a thumbnail of that size. Generating") + + # Okay, so we generate one. + file_path = await self.media_repo.generate_remote_exact_thumbnail( + server_name, + file_id, + media_id, + desired_width, + desired_height, + desired_method, + desired_type, + ) + + if file_path: + await respond_with_file(request, desired_type, file_path) + else: + logger.warning("Failed to generate thumbnail") + raise SynapseError(400, "Failed to generate thumbnail.") + + async def respond_remote_thumbnail( + self, + request: SynapseRequest, + server_name: str, + media_id: str, + width: int, + height: int, + method: str, + m_type: str, + max_timeout_ms: int, + ) -> None: + # TODO: Don't download the whole remote file + # We should proxy the thumbnail from the remote server instead of + # downloading the remote file and generating our own thumbnails. + media_info = await self.media_repo.get_remote_media_info( + server_name, media_id, max_timeout_ms + ) + if not media_info: + return + + thumbnail_infos = await self.store.get_remote_media_thumbnails( + server_name, media_id + ) + await self._select_and_respond_with_thumbnail( + request, + width, + height, + method, + m_type, + thumbnail_infos, + media_id, + media_info.filesystem_id, + url_cache=False, + server_name=server_name, + ) + + async def _select_and_respond_with_thumbnail( + self, + request: SynapseRequest, + desired_width: int, + desired_height: int, + desired_method: str, + desired_type: str, + thumbnail_infos: List[ThumbnailInfo], + media_id: str, + file_id: str, + url_cache: bool, + server_name: Optional[str] = None, + ) -> None: + """ + Respond to a request with an appropriate thumbnail from the previously generated thumbnails. + + Args: + request: The incoming request. + desired_width: The desired width, the returned thumbnail may be larger than this. + desired_height: The desired height, the returned thumbnail may be larger than this. + desired_method: The desired method used to generate the thumbnail. + desired_type: The desired content-type of the thumbnail. + thumbnail_infos: A list of thumbnail info of candidate thumbnails. + file_id: The ID of the media that a thumbnail is being requested for. + url_cache: True if this is from a URL cache. + server_name: The server name, if this is a remote thumbnail. + """ + logger.debug( + "_select_and_respond_with_thumbnail: media_id=%s desired=%sx%s (%s) thumbnail_infos=%s", + media_id, + desired_width, + desired_height, + desired_method, + thumbnail_infos, + ) + + # If `dynamic_thumbnails` is enabled, we expect Synapse to go down a + # different code path to handle it. + assert not self.dynamic_thumbnails + + if thumbnail_infos: + file_info = self._select_thumbnail( + desired_width, + desired_height, + desired_method, + desired_type, + thumbnail_infos, + file_id, + url_cache, + server_name, + ) + if not file_info: + logger.info("Couldn't find a thumbnail matching the desired inputs") + respond_404(request) + return + + # The thumbnail property must exist. + assert file_info.thumbnail is not None + + responder = await self.media_storage.fetch_media(file_info) + if responder: + await respond_with_responder( + request, + responder, + file_info.thumbnail.type, + file_info.thumbnail.length, + ) + return + + # If we can't find the thumbnail we regenerate it. This can happen + # if e.g. we've deleted the thumbnails but still have the original + # image somewhere. + # + # Since we have an entry for the thumbnail in the DB we a) know we + # have have successfully generated the thumbnail in the past (so we + # don't need to worry about repeatedly failing to generate + # thumbnails), and b) have already calculated that appropriate + # width/height/method so we can just call the "generate exact" + # methods. + + # First let's check that we do actually have the original image + # still. This will throw a 404 if we don't. + # TODO: We should refetch the thumbnails for remote media. + await self.media_storage.ensure_media_is_in_local_cache( + FileInfo(server_name, file_id, url_cache=url_cache) + ) + + if server_name: + await self.media_repo.generate_remote_exact_thumbnail( + server_name, + file_id=file_id, + media_id=media_id, + t_width=file_info.thumbnail.width, + t_height=file_info.thumbnail.height, + t_method=file_info.thumbnail.method, + t_type=file_info.thumbnail.type, + ) + else: + await self.media_repo.generate_local_exact_thumbnail( + media_id=media_id, + t_width=file_info.thumbnail.width, + t_height=file_info.thumbnail.height, + t_method=file_info.thumbnail.method, + t_type=file_info.thumbnail.type, + url_cache=url_cache, + ) + + responder = await self.media_storage.fetch_media(file_info) + await respond_with_responder( + request, + responder, + file_info.thumbnail.type, + file_info.thumbnail.length, + ) + else: + # This might be because: + # 1. We can't create thumbnails for the given media (corrupted or + # unsupported file type), or + # 2. The thumbnailing process never ran or errored out initially + # when the media was first uploaded (these bugs should be + # reported and fixed). + # Note that we don't attempt to generate a thumbnail now because + # `dynamic_thumbnails` is disabled. + logger.info("Failed to find any generated thumbnails") + + assert request.path is not None + respond_with_json( + request, + 400, + cs_error( + "Cannot find any thumbnails for the requested media ('%s'). This might mean the media is not a supported_media_format=(%s) or that thumbnailing failed for some other reason. (Dynamic thumbnails are disabled on this server.)" + % ( + request.path.decode(), + ", ".join(THUMBNAIL_SUPPORTED_MEDIA_FORMAT_MAP.keys()), + ), + code=Codes.UNKNOWN, + ), + send_cors=True, + ) + + def _select_thumbnail( + self, + desired_width: int, + desired_height: int, + desired_method: str, + desired_type: str, + thumbnail_infos: List[ThumbnailInfo], + file_id: str, + url_cache: bool, + server_name: Optional[str], + ) -> Optional[FileInfo]: + """ + Choose an appropriate thumbnail from the previously generated thumbnails. + + Args: + desired_width: The desired width, the returned thumbnail may be larger than this. + desired_height: The desired height, the returned thumbnail may be larger than this. + desired_method: The desired method used to generate the thumbnail. + desired_type: The desired content-type of the thumbnail. + thumbnail_infos: A list of thumbnail infos of candidate thumbnails. + file_id: The ID of the media that a thumbnail is being requested for. + url_cache: True if this is from a URL cache. + server_name: The server name, if this is a remote thumbnail. + + Returns: + The thumbnail which best matches the desired parameters. + """ + desired_method = desired_method.lower() + + # The chosen thumbnail. + thumbnail_info = None + + d_w = desired_width + d_h = desired_height + + if desired_method == "crop": + # Thumbnails that match equal or larger sizes of desired width/height. + crop_info_list: List[ + Tuple[int, int, int, bool, Optional[int], ThumbnailInfo] + ] = [] + # Other thumbnails. + crop_info_list2: List[ + Tuple[int, int, int, bool, Optional[int], ThumbnailInfo] + ] = [] + for info in thumbnail_infos: + # Skip thumbnails generated with different methods. + if info.method != "crop": + continue + + t_w = info.width + t_h = info.height + aspect_quality = abs(d_w * t_h - d_h * t_w) + min_quality = 0 if d_w <= t_w and d_h <= t_h else 1 + size_quality = abs((d_w - t_w) * (d_h - t_h)) + type_quality = desired_type != info.type + length_quality = info.length + if t_w >= d_w or t_h >= d_h: + crop_info_list.append( + ( + aspect_quality, + min_quality, + size_quality, + type_quality, + length_quality, + info, + ) + ) + else: + crop_info_list2.append( + ( + aspect_quality, + min_quality, + size_quality, + type_quality, + length_quality, + info, + ) + ) + # Pick the most appropriate thumbnail. Some values of `desired_width` and + # `desired_height` may result in a tie, in which case we avoid comparing on + # the thumbnail info and pick the thumbnail that appears earlier + # in the list of candidates. + if crop_info_list: + thumbnail_info = min(crop_info_list, key=lambda t: t[:-1])[-1] + elif crop_info_list2: + thumbnail_info = min(crop_info_list2, key=lambda t: t[:-1])[-1] + elif desired_method == "scale": + # Thumbnails that match equal or larger sizes of desired width/height. + info_list: List[Tuple[int, bool, int, ThumbnailInfo]] = [] + # Other thumbnails. + info_list2: List[Tuple[int, bool, int, ThumbnailInfo]] = [] + + for info in thumbnail_infos: + # Skip thumbnails generated with different methods. + if info.method != "scale": + continue + + t_w = info.width + t_h = info.height + size_quality = abs((d_w - t_w) * (d_h - t_h)) + type_quality = desired_type != info.type + length_quality = info.length + if t_w >= d_w or t_h >= d_h: + info_list.append((size_quality, type_quality, length_quality, info)) + else: + info_list2.append( + (size_quality, type_quality, length_quality, info) + ) + # Pick the most appropriate thumbnail. Some values of `desired_width` and + # `desired_height` may result in a tie, in which case we avoid comparing on + # the thumbnail info and pick the thumbnail that appears earlier + # in the list of candidates. + if info_list: + thumbnail_info = min(info_list, key=lambda t: t[:-1])[-1] + elif info_list2: + thumbnail_info = min(info_list2, key=lambda t: t[:-1])[-1] + + if thumbnail_info: + return FileInfo( + file_id=file_id, + url_cache=url_cache, + server_name=server_name, + thumbnail=thumbnail_info, + ) + + # No matching thumbnail was found. + return None |