In MBS, there are two cases to send a message when a module build moves
to a new state. One is to create a new module build, with
ModuleBuild.create particularly, when user submit a module build.
Another one is to transition a module build to a new state with
ModuleBuild.transition. This commit handles these two cases in a little
different ways.
For the former, existing code is refactored by moving the publish call
outside ModuleBuild.create.
For the latter, message is sent in a hook of SQLAlchemy ORM event
after_commit rather than immediately inside the ModuleBuild.transition.
Both of these changes ensure the message is sent after the changes are
committed into database successfully. Then, the backend can have
confidence that the database has the module build data when receive a
message.
Signed-off-by: Chenxiong Qi <cqi@redhat.com>
