addurl --file: Fix a bug that made youtube-dl be used unneccessarily when adding an html url that does not contain any media.

CHANGELOG

@@ -23,6 +23,8 @@ git-annex (7.20190220) UNRELEASED; urgency=medium
   * Fix cleanup of git-annex:export.log after git-annex forget --drop-dead.
   * Makefile: Added install-home target which installs git-annex into
     the HOME directory.
+  * addurl --file: Fix a bug that made youtube-dl be used unneccessarily
+    when adding an html url that does not contain any media.
 
  -- Joey Hess <id@joeyh.name>  Wed, 20 Feb 2019 14:20:59 -0400
 

Command/AddUrl.hs

@@ -277,7 +277,6 @@ downloadWeb o url urlinfo file =
 		liftIO $ createDirectoryIfMissing True (parentDir file)
 		finishDownloadWith tmp webUUID url file
 	tryyoutubedl tmp
-		| isJust (fileOption o) = dl file
 		-- Ask youtube-dl what filename it will download
 		-- first, and check if that is already an annexed file,
 		-- to avoid unnecessary work in that case.
@@ -286,6 +285,12 @@ downloadWeb o url urlinfo file =
 				(alreadyannexed dest)
 				(dl dest)
 			Left _ -> normalfinish tmp
+		-- Ask youtube-dl what filename it will download
+		-- fist, so it's only used when the file contains embedded
+		-- media.
+		| isJust (fileOption o) = youtubeDlFileNameHtmlOnly url >>= \case
+			Right _ -> dl file
+			Left _ -> normalfinish tmp
 	  where
 		dl dest = withTmpWorkDir mediakey $ \workdir -> do
 			let cleanuptmp = pruneTmpWorkDirBefore tmp (liftIO . nukeFile)

doc/bugs/addurl_fails_with_non-youtube_url_with___34__This_url_is_supported_by_youtube-dl__44___but_youtube-dl_could_potentially_access_any_address__34__.mdwn

@@ -29,3 +29,5 @@ local repository version: 5
 The same happens if I remove `youtube-dl` from the system entirely!
 [[!meta author=yoh]]
 
+> due to using --file which bypasses the usual check that youtube-dl
+> can extract media. [[fixed|done]] --[[Joey]]