The variable is still rturned even if it is not defined in configuration

[sshishov]

Let assume that we have this environment variables set on environment:

export VAR1=var1 VAR2=var2

Then we have the following piece of code:

from environ import Env

my_env = Env(VAR1=str)

print(my_env('VAR1'))  # var1
print(my_env('VAR2'))  # I would like it to fail as this variable is not defined in configuration, but it returns var2

I expect that the second call should fail with some error because this variable is not defined in the configuration.

If it is expected behavior, then I would like to have this configuration to enforce it.

Why? Because sometimes user do mistakes, define configuration as 1 variable and then use variable with typo when they access it, in this case the default casting is not applied which can lead to some issues.

UPDATE with example with boolean and casting:

export VAR1=True VAR2=False VAR3=True VAR4=False

from environ import Env

my_env = Env(VAR1=bool, VAR2=bool)

# usual print everything looks the same
print([str(value) for value in [my_env('VAR1'), my_env('VAR2'), my_env('VAR3'), my_env('VAR4')]]) 
# ['True', 'False', 'True', 'False']

# repr produces the differences in the type
print([repr(value) for value in [my_env('VAR1'), my_env('VAR2'), my_env('VAR3'), my_env('VAR4')]]) 
# ['True', 'False', "'True'", "'False'"]

# when will be used in `if` clauses, unexpected behavior can happen
print([bool(value) for value in [my_env('VAR1'), my_env('VAR2'), my_env('VAR3'), my_env('VAR4')]]) 
# [True, False, True, True]


Best regards,
    Sergei