Expose runtime api for runtime-specific Proxy pallet types configuration

[valentunn]

Is there an existing issue?

• I have searched the existing issues

Experiencing problems? Have you tried our Stack Exchange first?

• This is not a support question.

Motivation

It would be beneficial for wallets or dapps to be able to obtain the following information from the chain:

• Whather a certain RuntimeCall passes InstanceFilter for a certain ProxyType
• Whather one ProxyType is superset of another ProxyType

to be able to easily support "smart" proxy managment features on any Substrate chain with proxy pallet

Request

I would like to propose a new runtime api, e.g. ProxyApi with the following methods (or similar):

1. check_permissions(call: RuntimeCall, proxyType: ProxyType) : boolean
2. is_superset(type: ProxyType, against: ProxyType): boolean

Solution

Alternative solution would be to use already existing DryRunApi to simluate the actuall call execution, but the requested feature will provide more ergonomics compared to DryRunApi which is a general-purpose API

Are you willing to help with this request?

No.

[Nathy-bajo]

@valentunn Can I attempt this?
From my understanding, it involves changing the Proxy pallet to introduce a runtime API for checking RuntimeCall permissions and relationships between ProxyType variants.

[valentunn]

Hey @Nathy-bajo I am not involved in polkadot-sdk development so I can't really tell whether it is ok for you to take this into the work or not as I dont know the established processes to work on the issues

But I would definitely love to see this feature request to be taken into work that quickly!

Regarding the scope of the work - yes, what you described was my initial idea on how to solve this: the new Runtime API that calls already implemented instance filter and is_superset function

[bkchr]

@valentunn Can I attempt this?

You can take this if you like :)

From my understanding, it involves changing the Proxy pallet to introduce a runtime API for checking RuntimeCall permissions and relationships between ProxyType variants.

More like adding a runtime api to the proxy pallet crate, but yes!

[Nathy-bajo]

@valentunn Can I attempt this?

You can take this if you like :)

From my understanding, it involves changing the Proxy pallet to introduce a runtime API for checking RuntimeCall permissions and relationships between ProxyType variants.

More like adding a runtime api to the proxy pallet crate, but yes!

I just dropped a PR. Please review!

[kianenigma]

@re-gius @Nathy-bajo can you explore implementing this as a pallet view function please?

It is an experimental feature, but it will be integrated much easier into all runtimes that have the proxy pallet, rather than relying on custom runtime API to be added (assuming the runtime opts into view functions, which is a one-time operation).