What is the best technique with rethinkb and python to deal with empty result. I try this, but catching exceptions is not satisfactory.
@staticmethod
def get_by_mail(mail):
try:
return User(
r.table('users').filter({"mail": mail}).limit(1).nth(0).run()
)
except RqlRuntimeError:
return None
If anyone has tried other techniques, I am very interested. Thanks for your help.
The easiest way to deal with this is probably by adding in the element you want back with a union.
r.table('users').filter({"mail": mail}).limit(1).union([{}])[0]
A slightly ugly work around but it should do the trick. I think we should probably extend the default syntax to work with this. I'm going to make an issue for that.
That should work
r.table('users').filter({"mail": mail}).do( lambda users:
r.branch(
users.count() == 1,
users.nth(0),
None
)
)
You can also remove the nth(0) and retrieve a cursor and do:
user = None
for i in user:
user = i
break # You don't really need to break since there is at most one element
