Waku mailserver implementation

[oskarth]

Currently the Whisper implementation is lacking a mailserver implementation. I'd love to be able to start my nim-eth whisper node with mailserver capability! Initially for experimentation, later for production.

Here's what it would have to implement:

https://github.com/status-im/specs/blob/master/status-whisper-mailserver-spec.md

  proc p2pRequest(peer: Peer, envelope: Envelope) =
    # TODO: here we would have to allow to insert some specific implementation
    # such as e.g. Whisper Mail Server
    discard

In a first implementation, an in-memory database seems ok to me.

---

As an aside, can I start nim-eth as a bootnode? A naive grep didn't find anything straight away.

^ @kdeme

[kdeme]

@oskarth re the bootnode with nim-eth. I used to work with a bootnode in the whisper tests but replaced it with direct connecting for having more deterministic and faster tests.

However the helper code is still around. In the end it is nothing more than starting a discovery node. I'm guessing that for your use case (the usual use case for a bootnode) you would want to change it to have a fixed private key though.

[oskarth]

One thing I don't like about how the Go code works right now is that all bootnode/Whisper/mailserver/light node stuff is separated. IMO ideally it's a single node with different capabilities, so I can choose to be a discovery node, store expired envelopes, relay messages, etc.

[zah]

With the Nimbus codebase, the solution would probably look like this:

var node = newEthereumNode(localKeys, localAddress, 1, nil,
                           addAllCapabilities = false,
                           useCompression = useCompression)

node.addCapability Whisper
node.configureWhisper(storeExpiredEnvelopes = true,
                      relayMessages = true)

[oskarth]

Might be worth distinguishing between:

• Mailserver client
• Mailserver

Perhaps we want to split this into two issues?

[kdeme]

I'm guessing the client side is probably only implementation of one message packet id, so it could be covered by status-im/nim-eth#123 .

Should be noted though that Status mailserver implementation is apparently different from the original one, so if after specs update it turns out to be more work we can split.
To be clear, this issue is about implementing the Status version of mailserver.

[oskarth]

cc @adambabik re mailserver spec

[adambabik]

A bit more details: status-im/specs#64

[oskarth]

@kdeme I think having a mailserver client mode would be super useful for testing bw stuff, and it'd also be useful for making status-nim impl more useful in app.

What do you think? Do you need help with this?

[kdeme]

@oskarth started on it: status-im/nim-eth#141

I'll need some clarification though, or dig in the go code.

[oskarth]

Duplicate of #75 which is more up to date