Lazy context

[bcebere]

Description

This PR introduces the capability of loading a protobuffer without having the context linked yet.
fixes #193

Checklist

• I have followed the Contribution Guidelines and Code of Conduct
• I have commented my code following the OpenMined Styleguide
• I have labeled this PR with the relevant Type labels
• My changes are covered by tests

[youben11]

Nice and clean! I'm now wondering what happens when we run an operation which requires the tenseal_context? A way to deal with this is to always fetch the tenseal_context using the get method tenseal_context(), which will handle the case when the tensor is still lazy loaded, throwing an error message to the user. What do you think?

[bcebere]

Nice and clean! I'm now wondering what happens when we run an operation which requires the tenseal_context? A way to deal with this is to always fetch the tenseal_context using the get method tenseal_context(), which will handle the case when the tensor is still lazy loaded, throwing an error message to the user. What do you think?

There was another attempt in the PR, but I reverted, you can see here that I was going for a "call guardian" at first b2533dc.
But the changes were too big for the gain.

Yeah, I will check to use tenseal_context everywhere, it is easier.

[youben11]

Nice and clean! I'm now wondering what happens when we run an operation which requires the tenseal_context? A way to deal with this is to always fetch the tenseal_context using the get method tenseal_context(), which will handle the case when the tensor is still lazy loaded, throwing an error message to the user. What do you think?

There was another attempt in the PR, but I reverted, you can see here that I was going for a "call guardian" at first b2533dc.
But the changes were too big for the gain.

Yeah, I will check to use tenseal_context everywhere, it is easier.

I think as far as it's clear that the tenseal context is a private attribute and shouldn't be used directly (we can mention that in the documentation => this makes me remember that I really need to start documenting my code :p ) we should be good with throwing an error on the getter.

[bcebere]

Nice and clean! I'm now wondering what happens when we run an operation which requires the tenseal_context? A way to deal with this is to always fetch the tenseal_context using the get method tenseal_context(), which will handle the case when the tensor is still lazy loaded, throwing an error message to the user. What do you think?

There was another attempt in the PR, but I reverted, you can see here that I was going for a "call guardian" at first b2533dc.
But the changes were too big for the gain.
Yeah, I will check to use tenseal_context everywhere, it is easier.

I think as far as it's clear that the tenseal context is a private attribute and shouldn't be used directly (we can mention that in the documentation => this makes me remember that I really need to start documenting my code :p ) we should be good with throwing an error on the getter.

We can make the tenseal contexr private in the encrypted_tensor instead of protected, and this way we'd be sure that everyone is using it via tenseal_context(), even the derived classes.

[youben11]

Yeah, this would work perfectly I guess

[bcebere]

Yeah, this would work perfectly I guess

Actually, we already use tenseal_context in the derived classes, but we need to access _context for the lazy loading, instead of throwing an exception. So, there isn't much too do other than adding a guardian for all calls, to do sanity checks. But I think that is a bit overkill.

[youben11]

Yeah, I also agree that we shouldn't go for the guardian thing. If there isn't any way to allow only the lazy loader to access that private attribute, then we should leave it protected but make it clear that getting that attribute is forbidden by the supreme court

[bcebere]

Yeah, I also agree that we shouldn't go for the guardian thing. If there isn't any way to allow only the lazy loader to access that private attribute, then we should leave it protected but make it clear that getting that attribute is forbidden by the supreme court

updated

[youben11]

Even better this way! LGTM!