_context.py: Fix quota error when cas directory does not exist yet

If the quota is configured as percentage of total disk space, we need to
make sure that _get_volume_size() does not fail if the cas directory
does not exist yet.

1 files changed, 6 insertions, 2 deletions

diff --git a/src/buildstream/_context.py b/src/buildstream/_context.py
index b70f80d73..0d250eb56 100644
--- a/src/buildstream/_context.py
+++ b/src/buildstream/_context.py
@@ -270,14 +270,18 @@ class Context():
 
         # Load quota configuration
         # We need to find the first existing directory in the path of our
-        # cachedir - the cachedir may not have been created yet.
+        # casdir - the casdir may not have been created yet.
         cache = defaults.get_mapping('cache')
         cache.validate_keys(['quota', 'pull-buildtrees', 'cache-buildtrees'])
 
+        cas_volume = self.casdir
+        while not os.path.exists(cas_volume):
+            cas_volume = os.path.dirname(cas_volume)
+
         self.config_cache_quota_string = cache.get_str('quota')
         try:
             self.config_cache_quota = utils._parse_size(self.config_cache_quota_string,
-                                                        self.casdir)
+                                                        cas_volume)
         except utils.UtilError as e:
             raise LoadError("{}\nPlease specify the value in bytes or as a % of full disk space.\n"
                             "\nValid values are, for example: 800M 10G 1T 50%\n"