sqlalchemy - Stop random "Parent instance is not bound to a Session" -


i know simmilar questions have been answered here, thing is:

i have unit tests , run okay, "parent instance not bound session"

so how start debugging if happens randomly.

oh, , call before error db.session.add(my_item).

how happens? starting point put breakpoint of favorite python debugger (pdb) on line exception thrown. then, when encounter error inspect application state in python debugger, step in stack frames , figure out how application ended in such state.

also extensive use of python loggers , writing out debug log level messages pinpoint actual cause of error.


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