feat: allow custom registrar

[dozyio]

Description

Allow the registrar to be overridden with a custom implementation e.g. for adding protocol middleware

Notes & open questions

Change checklist

• I have performed a self-review of my own code
• I have made corresponding changes to the documentation if necessary (this includes comments as well)
• I have added tests that prove my fix is effective or that my feature works

[wemeetagain]

I suppose this should be in an else block on L143?

[dozyio]

Initially it was an if/else but found it useful to have the default implementation initialised so that it can be passed to a custom registrar. Maybe the initialisation of the default could be handled in the custom one instead?

https://github.com/dozyio/js-libp2p-middleware-registrar/blob/092687470ccd768da81d9d2044ce8ae37ce5715b/src/middleware-registry.ts#L101

[SgtPooki]

Allow the registrar to be overridden with a custom implementation e.g. for adding protocol middleware

Do you have an example of how you intend this to be used? Does this just make js-libp2p more customize-able without needing changes to the repo?

[dozyio]

Allow the registrar to be overridden with a custom implementation e.g. for adding protocol middleware

Do you have an example of how you intend this to be used? Does this just make js-libp2p more customize-able without needing changes to the repo?

Yes - examples here
https://github.com/dozyio/js-libp2p-middleware-registrar - adds a middleware registrar
https://github.com/dozyio/js-libp2p-middleware-evm - adds EVM auth middleware via the middleware-registrar
https://github.com/dozyio/evm-frontend-example - nextjs app using EVM middleware to wrap libp2p protocols - bit of a pain to setup at present - will add some docs later

Maybe the middleware registrar could be included in js-libp2p instead but happy for it to live outside of the tree for now