[cwvreg] cleanup the event manager when reloading modules
Closes #3848995
The event manager callbacks are not cleaned during reloading.
So the callback defined in the reloaded module appears twice (old and new
version). This may cause problem when the old version is called.
from yams import schema2sql as y2sql
dbhelper = repo.system_source.dbhelper
rdefdef = schema['CWSource'].rdef('name')
attrtype = y2sql.type_from_constraints(dbhelper, rdefdef.object, rdefdef.constraints).split()[0]
cursor = session.cnxset['system']
sql('UPDATE entities SET asource = source WHERE asource is NULL')
dbhelper.change_col_type(cursor, 'entities', 'asource', attrtype, False)
dbhelper.change_col_type(cursor, 'entities', 'source', attrtype, False)
dbhelper.change_col_type(cursor, 'deleted_entities', 'source', attrtype, False)