1 files changed, 80 insertions, 1 deletions
diff --git a/buildstream/_ostree.py b/buildstream/_ostree.py
index 6fee37dc0..217790d84 100644
--- a/buildstream/_ostree.py
+++ b/buildstream/_ostree.py
@@ -1,4 +1,3 @@
-#!/usr/bin/env python3
 #
 #  Copyright (C) 2017 Codethink Limited
 #
@@ -150,6 +149,42 @@ def exists(repo, ref):
     return has_object
 
 
+# remove():
+#
+# Removes the given commit or symbolic ref from the repo.
+#
+# Args:
+#    repo (OSTree.Repo): The repo
+#    ref (str): A commit checksum or symbolic ref
+#    defer_prune (bool): Whether to defer pruning to the caller. NOTE:
+#                        The space won't be freed until you manually
+#                        call repo.prune.
+#
+# Returns:
+#    (int|None) The amount of space pruned from the repository in
+#               Bytes, or None if defer_prune is True
+#
+def remove(repo, ref, *, defer_prune=False):
+
+    # Get the commit checksum, this will:
+    #
+    #  o Return a commit checksum if ref is a symbolic branch
+    #  o Return the same commit checksum if ref is a valid commit checksum
+    #  o Return None if the ostree repo doesnt know this ref.
+    #
+    check = checksum(repo, ref)
+    if check is None:
+        raise OSTreeError("Could not find artifact for ref '{}'".format(ref))
+
+    repo.set_ref_immediate(None, ref, None)
+
+    if not defer_prune:
+        _, _, _, pruned = repo.prune(OSTree.RepoPruneFlags.REFS_ONLY, -1)
+        return pruned
+
+    return None
+
+
 # checksum():
 #
 # Returns the commit checksum for a given symbolic ref,
@@ -275,3 +310,47 @@ def configure_remote(repo, remote, url, key_url=None):
             repo.remote_gpg_import(remote, stream, None, 0, None)
         except GLib.GError as e:
             raise OSTreeError("Failed to add gpg key from url '{}': {}".format(key_url, e.message)) from e
+
+
+# list_artifacts():
+#
+# List cached artifacts in Least Recently Modified (LRM) order.
+#
+# Returns:
+#     (list) - A list of refs in LRM order
+#
+def list_artifacts(repo):
+    # string of: /path/to/repo/refs/heads
+    ref_heads = os.path.join(repo.get_path().get_path(), 'refs', 'heads')
+
+    # obtain list of <project>/<element>/<key>
+    refs = _list_all_refs(repo).keys()
+
+    mtimes = []
+    for ref in refs:
+        ref_path = os.path.join(ref_heads, ref)
+        if os.path.exists(ref_path):
+            # Obtain the mtime (the time a file was last modified)
+            mtimes.append(os.path.getmtime(ref_path))
+
+    # NOTE: Sorted will sort from earliest to latest, thus the
+    # first element of this list will be the file modified earliest.
+    return [ref for _, ref in sorted(zip(mtimes, refs))]
+
+
+# _list_all_refs():
+#
+# Create a list of all refs.
+#
+# Args:
+#    repo (OSTree.Repo): The repo
+#
+# Returns:
+#    (dict): A dict of refs to checksums.
+#
+def _list_all_refs(repo):
+    try:
+        _, refs = repo.list_refs(None)
+        return refs
+    except GLib.GError as e:
+        raise OSTreeError(message=e.message) from e