Production incident: a customer's Facebook Page post failed with 'The post
is empty. Please enter a message to share.' (error code 197) and ended up
with a contradictory DB state (status=published + error_message=set).
Three independent bugs were uncovered:
A. FacebookPublisher sends 'message'/'description' as null when the user
posts media without text. Graph API requires the key be omitted, not
null. Fixed in publishSingleImagePost, publishMultiImagePost,
publishVideoPost, publishReel.
B. markAsPublished/markAsFailed leak stale fields across transitions
(a published row could retain error_message from a prior failure,
vice-versa). Both transitions now explicitly clear the opposite
side's fields.
C. status='failed' was editable in the UI and the backend, so users
were re-clicking Publish, generating duplicate failure emails and
the contradictory state from bug B. The frontend isReadOnly check
and the UpdatePost backend guard now treat Published/PartiallyPublished/
Failed/Publishing as terminal. To retry, the user duplicates the post.
11 new tests guarantee these can't regress silently: FB payload shape
per content type, PostPlatform field-clearing on transitions, and the
terminal-status block at the controller level.
