lsupstreams: Prefer more specific remote prefixes in prefixmap

In order to support Downstream Hosts with restricted repository
hierarchies (like Gitea's 2 levels), it is useful to be able to map
both a directory and a subdirectory of it from an Upstream Host that
has a deeper hierarchy.

Convert the prefixmap into a list of (remote, local) tuples and sort
in reverse order, so that a subdirectory prefix will appear before its
parent directory prefix if both are present.

1 files changed, 4 insertions, 3 deletions

diff --git a/lorrycontroller/lsupstreams.py b/lorrycontroller/lsupstreams.py
index a535174..0b0802a 100644
--- a/lorrycontroller/lsupstreams.py
+++ b/lorrycontroller/lsupstreams.py
@@ -94,12 +94,13 @@ class HostRepositoryLister(object):
         return repo_map
 
     def parse_prefixmap(self, prefixmap_string):
-        return json.loads(prefixmap_string)
+        # Sort prefixes in reverse order, so more specific prefixes
+        # come first
+        return sorted(json.loads(prefixmap_string).items(), reverse=True)
 
     def map_one_remote_repo_to_local_one(self, remote_path, prefixmap):
-        for remote_prefix in prefixmap:
+        for remote_prefix, local_prefix in prefixmap:
             if self.path_starts_with_prefix(remote_path, remote_prefix):
-                local_prefix = prefixmap[remote_prefix]
                 relative_path = remote_path[len(remote_prefix):]
                 local_path = local_prefix + relative_path
                 return local_path