add option funcs to WakuNode, add extraOptions to pass arbitrary config to nwaku

[vpavlin]

1. This adds option func (https://golang.cafe/blog/golang-functional-options-pattern.html) to WakuNode
2. Adds ExtraOptions - a map of string -> interface{} of options allowing to configure any of nwaku config options

Example:

node, err := NewWakuNode(&DefaultWakuConfig, "test", 
      WithExtraOptions(common.ExtraOptions{"rlnRelayEthClientAddress": "https://api.zan.top/eth-sepolia"}))

This will configure given URL as RLN RPC for nwaku

[gabrielmer]

Thanks so much! Just added a small question :))

[gabrielmer]

what does this do? not sure I follow it

[vpavlin]

Which is why I provided a link to the article in the description: https://golang.cafe/blog/golang-functional-options-pattern.html

TL;DR: It allows you to define and passing functions that get called automatically which adds more flexibility to configuration than a custom struct - same approach has been used in go-waku (https://github.com/waku-org/go-waku/blob/master/waku/v2/node/wakuoptions.go#L135), so then you end up with something like:

NewNode(something,
  WithTimeout(..),
  WithRLN(...),
  WIthGabrielsBrain(...),
  ...
 )

[gabrielmer]

Oooh makes sense! Thanks so much! 🤩

[Ivansete-status]

LGTM! Thanks for it! 💯
Maybe interesting to add a simple unit test showing how to use it

[vpavlin]

Maybe interesting to add a simple unit test showing how to use it

I am just not sure what the test should test:-) Like how do I "prove" the node is configured properly with that extra config? I am open to suggestions:-)

[Ivansete-status]

I am just not sure what the test should test:-) Like how do I "prove" the node is configured properly with that extra config? I am open to suggestions:-)

ah yes good point hehe ^^'
Maybe we could just try to start a node by using correct nodekey param (64-hex) and check that a node doesn't start correctly by setting a 63-long nodekey. That way we could see that the parameter is effectively being pushed to the node.