backend: skip invalid build directories

backend/run/copr-change-storage

@@ -51,6 +51,31 @@ def get_arg_parser():
     return parser
 
 
+def is_valid_build_directory(name):
+    """
+    See the `copr-backend-resultdir-cleaner`. We may want to share the code
+    between them.
+    """
+    if name in ["repodata", "devel"]:
+        return False
+
+    if name.startswith("repodata.old") or name.startswith(".repodata."):
+        return False
+
+    if name in ["tmp", "cache", "appdata"]:
+        return False
+
+    parts = name.split("-")
+    if len(parts) <= 1:
+        return False
+
+    number = parts[0]
+    if len(number) != 8 or any(not c.isdigit() for c in number):
+        return False
+
+    return True
+
+
 def main():
     """
     The main function
@@ -98,6 +123,10 @@ def main():
                 if not os.path.isdir(resultdir):
                     continue
 
+                if not is_valid_build_directory(builddir):
+                    log.info("Skipping: %s", resultdir)
+                    continue
+
                 full_name = "{0}/{1}".format(owner, subproject)
                 result = storage.init_project(full_name, chroot)
                 if not result: