Do not log warning on config files that represent None.

This issue was first identified when manual_cache_clean was set, as
ds-identify would write /run/cloud-init/cloud.cfg with
  # manual_cache_clean
that would generate a warning as cloud-init expected to load a dict.
Any other "empty" config would also log such a warning.

Also fix reading of di_report to allow it to be None, as ds-identify
would write:
  di_report:
    # manual_cache_clean
which reads as 'di_report: None' rather than di_report: {}.

LP: #1742479

1 files changed, 7 insertions, 1 deletions

diff --git a/cloudinit/cmd/main.py b/cloudinit/cmd/main.py
index 30b37fe1..d2f1b778 100644
--- a/cloudinit/cmd/main.py
+++ b/cloudinit/cmd/main.py
@@ -421,7 +421,13 @@ def di_report_warn(datasource, cfg):
         LOG.debug("no di_report found in config.")
         return
 
-    dicfg = cfg.get('di_report', {})
+    dicfg = cfg['di_report']
+    if dicfg is None:
+        # ds-identify may write 'di_report:\n #comment\n'
+        # which reads as {'di_report': None}
+        LOG.debug("di_report was None.")
+        return
+
     if not isinstance(dicfg, dict):
         LOG.warning("di_report config not a dictionary: %s", dicfg)
         return