How to set authorizer limits?

[pcolmer]

The documentation makes reference to "limits" as a single parameter.

The test code makes calls to "get_limits" but that doesn't appear to be in the latest version of the library.

Can you please provide a solid example of how to set authorizer limits in the Python language?

Thanks

[divarvel]

The unit tests should help you: https://github.com/eclipse-biscuit/biscuit-python/blob/main/biscuit_test.py#L200

where did you see get_limits used?

[pcolmer]

Sorry - I wrote this issue quickly after a frustrating day (literally) of trying to update my biscuit code to overcome a limits issue.

The problem I'm having is that the only example I can find of setting limits is that unit test ... and I am not using AuthorizerBuilder.

This is my code at the moment:

def create_authorizer(biscuit):
    authorizer = Authorizer( """ time({now}); """, { 'now': int(datetime.datetime.now().timestamp())} )
    authorizer.add_token(biscuit)
    authorizer.add_policy(Policy("allow if true"))
    authorizer.authorize()
    return authorizer

If I try something like limits = authorizer.limits() then Python says "Attribute limits is unknown".

So I'm stuck, hence my request for clearer documentation around limits.

[divarvel]

Ok, so what you actually want is an AuthorizerBuilder. Authorizer itself used to be mutable, but this caused all sorts of troubles, so now authorizer is a bit like Biscuit or Block: you go through a builder to actually build the datalog part, and then you turn it into an authorizer to actually run datalog. So for your example,

def create_authorizer(biscuit):
    builder = AuthorizerBuilder(
        """time({now}); allow if true;""",
        { 'now': int(datetime.datetime.now().timestamp())}
   )
   limits = builder.limits()
   limits.max_time = timedelta(microseconds=2000)
   builder.set_limits(limits)  
   return builder.build(biscuit)

this will return an Authorizer. you can call .authorize() to get the authorization results, query it with query(), etc. The limits set in the builder will be used. The rust library also supports authorize_with_limits() to override limits per call, but it’s not exposed in the python library for now.

[pcolmer]

Ah! Thank you.