Merge branch 'develop' into m-heroes-empty-room-name

6 files changed, 61 insertions, 2 deletions

diff --git a/synapse/rest/media/v1/_base.py b/synapse/rest/media/v1/_base.py
index e2b5df701d..2dcc8f74d6 100644
--- a/synapse/rest/media/v1/_base.py
+++ b/synapse/rest/media/v1/_base.py
@@ -191,6 +191,10 @@ def respond_with_responder(request, responder, media_type, file_size, upload_nam
         # in that case.
         logger.warning("Failed to write to consumer: %s %s", type(e), e)
 
+        # Unregister the producer, if it has one, so Twisted doesn't complain
+        if request.producer:
+            request.unregisterProducer()
+
     finish_request(request)
 
 
diff --git a/synapse/rest/media/v1/media_repository.py b/synapse/rest/media/v1/media_repository.py
index bdffa97805..8569677355 100644
--- a/synapse/rest/media/v1/media_repository.py
+++ b/synapse/rest/media/v1/media_repository.py
@@ -444,6 +444,9 @@ class MediaRepository(object):
             )
             return
 
+        if thumbnailer.transpose_method is not None:
+            m_width, m_height = thumbnailer.transpose()
+
         if t_method == "crop":
             t_byte_source = thumbnailer.crop(t_width, t_height, t_type)
         elif t_method == "scale":
@@ -578,6 +581,12 @@ class MediaRepository(object):
             )
             return
 
+        if thumbnailer.transpose_method is not None:
+            m_width, m_height = yield logcontext.defer_to_thread(
+                self.hs.get_reactor(),
+                thumbnailer.transpose
+            )
+
         # We deduplicate the thumbnail sizes by ignoring the cropped versions if
         # they have the same dimensions of a scaled one.
         thumbnails = {}
diff --git a/synapse/rest/media/v1/preview_url_resource.py b/synapse/rest/media/v1/preview_url_resource.py
index ba3ab1d37d..acf87709f2 100644
--- a/synapse/rest/media/v1/preview_url_resource.py
+++ b/synapse/rest/media/v1/preview_url_resource.py
@@ -31,6 +31,7 @@ from six.moves import urllib_parse as urlparse
 from canonicaljson import json
 
 from twisted.internet import defer
+from twisted.internet.error import DNSLookupError
 from twisted.web.resource import Resource
 from twisted.web.server import NOT_DONE_YET
 
@@ -328,9 +329,18 @@ class PreviewUrlResource(Resource):
                 # handler will return a SynapseError to the client instead of
                 # blank data or a 500.
                 raise
+            except DNSLookupError:
+                # DNS lookup returned no results
+                # Note: This will also be the case if one of the resolved IP
+                # addresses is blacklisted
+                raise SynapseError(
+                    502, "DNS resolution failure during URL preview generation",
+                    Codes.UNKNOWN
+                )
             except Exception as e:
                 # FIXME: pass through 404s and other error messages nicely
                 logger.warn("Error downloading %s: %r", url, e)
+
                 raise SynapseError(
                     500, "Failed to download content: %s" % (
                         traceback.format_exception_only(sys.exc_info()[0], e),
diff --git a/synapse/rest/media/v1/storage_provider.py b/synapse/rest/media/v1/storage_provider.py
index 5aa03031f6..d90cbfb56a 100644
--- a/synapse/rest/media/v1/storage_provider.py
+++ b/synapse/rest/media/v1/storage_provider.py
@@ -108,6 +108,7 @@ class FileStorageProviderBackend(StorageProvider):
     """
 
     def __init__(self, hs, config):
+        self.hs = hs
         self.cache_directory = hs.config.media_store_path
         self.base_directory = config
 
diff --git a/synapse/rest/media/v1/thumbnail_resource.py b/synapse/rest/media/v1/thumbnail_resource.py
index 5305e9175f..35a750923b 100644
--- a/synapse/rest/media/v1/thumbnail_resource.py
+++ b/synapse/rest/media/v1/thumbnail_resource.py
@@ -56,8 +56,8 @@ class ThumbnailResource(Resource):
     def _async_render_GET(self, request):
         set_cors_headers(request)
         server_name, media_id, _ = parse_media_id(request)
-        width = parse_integer(request, "width")
-        height = parse_integer(request, "height")
+        width = parse_integer(request, "width", required=True)
+        height = parse_integer(request, "height", required=True)
         method = parse_string(request, "method", "scale")
         m_type = parse_string(request, "type", "image/png")
 
diff --git a/synapse/rest/media/v1/thumbnailer.py b/synapse/rest/media/v1/thumbnailer.py
index a4b26c2587..3efd0d80fc 100644
--- a/synapse/rest/media/v1/thumbnailer.py
+++ b/synapse/rest/media/v1/thumbnailer.py
@@ -20,6 +20,17 @@ import PIL.Image as Image
 
 logger = logging.getLogger(__name__)
 
+EXIF_ORIENTATION_TAG = 0x0112
+EXIF_TRANSPOSE_MAPPINGS = {
+    2: Image.FLIP_LEFT_RIGHT,
+    3: Image.ROTATE_180,
+    4: Image.FLIP_TOP_BOTTOM,
+    5: Image.TRANSPOSE,
+    6: Image.ROTATE_270,
+    7: Image.TRANSVERSE,
+    8: Image.ROTATE_90
+}
+
 
 class Thumbnailer(object):
 
@@ -31,6 +42,30 @@ class Thumbnailer(object):
     def __init__(self, input_path):
         self.image = Image.open(input_path)
         self.width, self.height = self.image.size
+        self.transpose_method = None
+        try:
+            # We don't use ImageOps.exif_transpose since it crashes with big EXIF
+            image_exif = self.image._getexif()
+            if image_exif is not None:
+                image_orientation = image_exif.get(EXIF_ORIENTATION_TAG)
+                self.transpose_method = EXIF_TRANSPOSE_MAPPINGS.get(image_orientation)
+        except Exception as e:
+            # A lot of parsing errors can happen when parsing EXIF
+            logger.info("Error parsing image EXIF information: %s", e)
+
+    def transpose(self):
+        """Transpose the image using its EXIF Orientation tag
+
+        Returns:
+            Tuple[int, int]: (width, height) containing the new image size in pixels.
+        """
+        if self.transpose_method is not None:
+            self.image = self.image.transpose(self.transpose_method)
+            self.width, self.height = self.image.size
+            self.transpose_method = None
+            # We don't need EXIF any more
+            self.image.info["exif"] = None
+        return self.image.size
 
     def aspect(self, max_width, max_height):
         """Calculate the largest size that preserves aspect ratio which