Merge pull request #706 from apachelogger/fix-by-index-cleanup

Fix by by-hash index cleanup + root dir data "loss"

deb/index_files.go

@@ -191,18 +191,22 @@ func packageIndexByHash(file *indexFile, ext string, hash string, sum string) er
 	}
 
 	// if a previous index file already exists exists, backup symlink
-	if exists, _ = file.parent.publishedStorage.FileExists(filepath.Join(dst, indexfile)); exists {
+	indexPath := filepath.Join(dst, indexfile)
+	oldIndexPath := filepath.Join(dst, indexfile+".old")
+	if exists, _ = file.parent.publishedStorage.FileExists(indexPath); exists {
 		// if exists, remove old symlink
-		if exists, _ = file.parent.publishedStorage.FileExists(filepath.Join(dst, indexfile+".old")); exists {
+		if exists, _ = file.parent.publishedStorage.FileExists(oldIndexPath); exists {
-			var link string
+			var linkTarget string
-			link, err = file.parent.publishedStorage.ReadLink(filepath.Join(dst, indexfile+".old"))
+			linkTarget, err = file.parent.publishedStorage.ReadLink(oldIndexPath)
-			if err != nil {
+			if err == nil {
-				file.parent.publishedStorage.Remove(link)
+				// If we managed to resolve the link target: delete it. This is the
+				// oldest physical index file we no longer need. Once we drop our
+				// old symlink we'll essentially forget about it existing at all.
+				file.parent.publishedStorage.Remove(linkTarget)
 			}
-			file.parent.publishedStorage.Remove(filepath.Join(dst, indexfile+".old"))
+			file.parent.publishedStorage.Remove(oldIndexPath)
 		}
-		file.parent.publishedStorage.RenameFile(filepath.Join(dst, indexfile),
+		file.parent.publishedStorage.RenameFile(indexPath, oldIndexPath)
-			filepath.Join(dst, indexfile+".old"))
 	}
 
 	// create symlink

files/public.go

@@ -267,7 +267,12 @@ func (storage *PublishedStorage) FileExists(path string) (bool, error) {
 	return true, nil
 }
 
-// ReadLink returns the symbolic link pointed to by path
+// ReadLink returns the symbolic link pointed to by path (relative to storage
+// root)
 func (storage *PublishedStorage) ReadLink(path string) (string, error) {
-	return os.Readlink(path)
+	absPath, err := os.Readlink(filepath.Join(storage.rootPath, path))
+	if err != nil {
+		return absPath, err
+	}
+	return filepath.Rel(storage.rootPath, absPath)
 }

files/public_test.go

@@ -129,6 +129,10 @@ func (s *PublishedStorageSuite) TestSymLink(c *C) {
 
 	exists, _ := s.storage.FileExists("ppa/dists/squeeze/InRelease")
 	c.Check(exists, Equals, true)
+
+	linkTarget, err := s.storage.ReadLink("ppa/dists/squeeze/InRelease")
+	c.Assert(err, IsNil)
+	c.Assert(linkTarget, Equals, "ppa/dists/squeeze/Release")
 }
 
 func (s *PublishedStorageSuite) TestHardLink(c *C) {