fix: skip serialization of continuation token if None

[apoorvsadana]

In the Starknet Spec, the continuation_token is not a required field. So in the last event page, the continuation_token must be absent from the response instead of being null. I also tried this with the infura RPC (which uses pathfinder?) and works in the same way. We are integrating Madara with the explorer and that's breaking because of this.

[glihm]

Looks good, I would only add in the comment the reason why it's added. 👍

[apoorvsadana]

Done!

[xJonathanLEI]

Does this need to be backported or are you guys already using the latest commit?

[apoorvsadana]

We're already using a specific rev. We can change that to the latest one, shouldn't be an issue.

[xJonathanLEI]

Are you using an old rev with JSON-RPC pre-0.6.0 though? The latest commit uses pre-0.6.0.

[xJonathanLEI]

Or are you only using this one single type? Then it shouldn't matter. Not sure how the lib is used in Madara.

[xJonathanLEI]

LGTM. Thanks for spotting. Really all Option fields should be skipped for serialization when it's None.

[apoorvsadana]

We are using it for other things as well and currently Madara isn't on 0.6.0. So you're right, just updating the commit might break. We are on this rev right now - a35ce22. Is it possible to backport it?

[xJonathanLEI]

Oh that's a very old commit, not even JSON-RPC v0.5.1.. still on v0.4.0.

[xJonathanLEI]

In this case maybe you can backport this in a fork and use the fork for Madara until it upgrades?

[apoorvsadana]

Ya sure we can do that then. Thanks for the help!