From 2442e9876c2622e345ab62a414e509d4f5cecb4f Mon Sep 17 00:00:00 2001
From: Erik Johnston <erik@matrix.org>
Date: Tue, 9 Jan 2018 14:36:07 +0000
Subject: [PATCH] Make PreviewUrlResource use MediaStorage

---
 synapse/rest/media/v1/media_repository.py     |  4 +++-
 synapse/rest/media/v1/preview_url_resource.py | 18 +++++++++++-------
 2 files changed, 14 insertions(+), 8 deletions(-)

diff --git a/synapse/rest/media/v1/media_repository.py b/synapse/rest/media/v1/media_repository.py
index 0c84f1be0..9aba9f13f 100644
--- a/synapse/rest/media/v1/media_repository.py
+++ b/synapse/rest/media/v1/media_repository.py
@@ -642,4 +642,6 @@ class MediaRepositoryResource(Resource):
         ))
         self.putChild("identicon", IdenticonResource())
         if hs.config.url_preview_enabled:
-            self.putChild("preview_url", PreviewUrlResource(hs, media_repo))
+            self.putChild("preview_url", PreviewUrlResource(
+                hs, media_repo, media_repo.media_storage,
+            ))
diff --git a/synapse/rest/media/v1/preview_url_resource.py b/synapse/rest/media/v1/preview_url_resource.py
index 40d2e664e..f3dbbb3fe 100644
--- a/synapse/rest/media/v1/preview_url_resource.py
+++ b/synapse/rest/media/v1/preview_url_resource.py
@@ -17,6 +17,8 @@ from twisted.web.server import NOT_DONE_YET
 from twisted.internet import defer
 from twisted.web.resource import Resource
 
+from ._base import FileInfo
+
 from synapse.api.errors import (
     SynapseError, Codes,
 )
@@ -49,7 +51,7 @@ logger = logging.getLogger(__name__)
 class PreviewUrlResource(Resource):
     isLeaf = True
 
-    def __init__(self, hs, media_repo):
+    def __init__(self, hs, media_repo, media_storage):
         Resource.__init__(self)
 
         self.auth = hs.get_auth()
@@ -62,6 +64,7 @@ class PreviewUrlResource(Resource):
         self.client = SpiderHttpClient(hs)
         self.media_repo = media_repo
         self.primary_base_path = media_repo.primary_base_path
+        self.media_storage = media_storage
 
         self.url_preview_url_blacklist = hs.config.url_preview_url_blacklist
 
@@ -273,19 +276,21 @@ class PreviewUrlResource(Resource):
 
         file_id = datetime.date.today().isoformat() + '_' + random_string(16)
 
-        fpath = self.filepaths.url_cache_filepath_rel(file_id)
-        fname = os.path.join(self.primary_base_path, fpath)
-        self.media_repo._makedirs(fname)
+        file_info = FileInfo(
+            server_name=None,
+            file_id=file_id,
+            url_cache=True,
+        )
 
         try:
-            with open(fname, "wb") as f:
+            with self.media_storage.store_into_file(file_info) as (f, fname, finish):
                 logger.debug("Trying to get url '%s'" % url)
                 length, headers, uri, code = yield self.client.get_file(
                     url, output_stream=f, max_size=self.max_spider_size,
                 )
                 # FIXME: pass through 404s and other error messages nicely
 
-            yield self.media_repo.copy_to_backup(fpath)
+                yield finish()
 
             media_type = headers["Content-Type"][0]
             time_now_ms = self.clock.time_msec()
@@ -327,7 +332,6 @@ class PreviewUrlResource(Resource):
             )
 
         except Exception as e:
-            os.remove(fname)
             raise SynapseError(
                 500, ("Failed to download content: %s" % e),
                 Codes.UNKNOWN