PSS messenger dapp

[aquiladev]

24 #25

[cobordism]

@zelig, @nolash, can you take a look at this?

[nolash]

@aquiladev writing to let you know that I've noticed the submission, but haven't so far had the bandwith to go through it. I hope to get back to you with a review early next week. In the meantime, thank you very much for your contribution.

[nolash]

@aquiladev I've had a look through the submission now, and I have a couple of questions:

• You seem to have chosen a client-server model here. What do you need the server for? Why can't it all be done within the browser directly from swarm like the other swarm dapps?
• Can I customize the host/port for the websocket when I start the application?

Thanks.

[aquiladev]

@nolash

• The dapp communicates with up and running swarm client, without intermediaries, so you can treat swarm as a server. The only difference between the dapp and others is that they use relative addresses (at least what I see). In the dapp I need to use websocket and I use Erebos library which communicates with swarm. The library needs urls for connection to http and websocket endpoints of swarm
• There is no setting for websocket endpoint yet

[nolash]

@aquiladev ok I understand, thanks.

I gave it a spin with @justelad and we were able to add each other and exchange messages. So far so good. Some questions regarding the pss implementation:

• adding contact is pubkey only, no swarm address. is the address handled in the contact request/response?
• what happens if the internet connection goes down temporarily. Does the app rebuild the websocket connection?
• could you please display the full pubkey in the brower app (or even better, display first and last bytes, with a copy-full-key-hex--to-clipboard mechanism?)
• would you consider adding websocket endpoint?

I'm not qualified to do a proper review of a react app, so @justelad will be taking care of that in the near future.

THanks.

[aquiladev]

Hi @nolash,

1. I suppose Erebos library handles it
2. In case of connection lose it will not be restored automatically, the dapp should be refreshed in order to receive/send messages
3. I will implement formatting (display first and last bytes) with copy-to-clipboard
4. Where do you think it would be better to set ws endpoint? I can show popup with ws endpoint field on dapp's start

[nolash]

1. No, it can't because it has no way of knowing. Either the address must be explicitly given by the user, or it would have to be part of the request/response handshake where the peer voluntarily discloses its address. You can specify anything from 0 to 32 bytes of address. The more bytes you specify, the more efficient the routing will be. Right now it's in effect 0 bytes, which means it sends all messages to all peers (along the lines of the basic strategy of whisper). The main point of pss, however, is to provide message routing; a tradeoff of secrecy for efficiency. So could we do either one of the two?

2. I see. So, if the work is to be continued into "goal 2," I'd prefer if we include in the next step address connection restoration within a session, agree?

3. Great

4. Yes, either popup or just a div over the pubkey fields with defaults already filled in that disappears when you click connect. You choose.

Thanks again.

[aquiladev]

1. Not sure that I fully understood it, I will spend time to investigate it Current implementation: 1) on app start I retrieve base address by pss_baseAddr and public key by pss_getPublicKey 2) send contact request:
   • set peer pss_setPeerPublicKey {receiverPublicKey} {topic}
   • send message pss_sendAsym {receiverPublicKey} {topic} {message}, message contains base address of sender 3) accept request by contact:
   • set peer pss_setPeerPublicKey {senderPublicKey} {topic}
   • send message pss_sendAsym {senderPublicKey} {topic} {message}, message contains base address of receiver 4) exchange messages pss_sendAsym {publicKey} {topic} {message}

Would you please point me to the place regarding the address?

2. Agree
3. Done
4. Done (Pushed changes)

[nolash]

send message pss_sendAsym {senderPublicKey} {topic} {message}, message contains base address of receiver

@aquiladev aha so it is handled in the contact request/response then? The full address of the requester is set with setPeerPublicKey on the receiver, and the requester updates from the address in the response? If it's done like this it's all fine.

... I mean - ideally sliding scale "luminosity," of course, but that's for later :)

[nolash]

HOWEVER - I see in your calls to setPeerPublicKey in /examples/messenger/src/base/messenger.js the address argument is omitted. That translates to an zero-byte address. Even if your application message struct contains the address, there is no software that automagically sets this for you.

[nolash]

Oh and I forgot one more thing:

Could you please remove the leading / in the resource paths? Or are they necessary? Without them the app can be served from a subfolder.

[aquiladev]

@nolash there is no routing, / is not needed and not used

[nolash]

If I put the app on my webserver at localhost/messenger lets say, I get a bunch of 404s when trying to load.

[nolash]

@aquiladev the address stuff seems to work. Good! Curious: If I first send 0x as the address, it gets updated on the response, right?

[nolash]

The websocket popup, if I give an alternate value (port 8547 for example) and press enter, the popup just pops back, if I press the button, it works.

[aquiladev]

@nolash

• I've figured out issue with routing, it should be fixed. In order to deploy the dapp you need build (npm run build), then copy artifact to target location
• In case of empty address the request will be broadcasted. When receiver accept request, requester will receive and create a peer with address of receiver.
• I fixed issue with enter

[nolash]

Great! That's all from me. Thanks :)

[aquiladev]

@justelad I agree that the solution design may look not good, can be heavily improved, but this is example dapp, I think it is not needed here