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(Photo by Alice Dietrich on Unsplash)
Sia and Namebase recently held a hackathon via gitcoin in which one of the goals was to build an application with handshake, a decentralized certificate and naming authority. This is a quick recap of the project I made for the hackathon. The repo can be found at handybot.
Handshake is a promising young project, which is now live, that aims to offer an alternative to the current Domain Name System (DNS). I have been following the project and was interested in its progress. The hackathon presented an opportunity to learn more about the tech stack of the project, and get my hands dirty in trying to make an application that integrated with the Handshake network.
Namebase, one of the sponsors, offers a platform to manage domains that are registered on the network, and to buy and sell $HNS (the native token for the Handshake network). In thinking of a compelling application to make for the hackathon, I narrowed focus on the public API Namebase has for domain resource information: /api/v0/dns/domains/:domain
In having some familiarity with calling APIs, I was hoping that the domain API offered by Namebase would serve as a public interface for accessing the domain records that exist on the Handshake network. One of the compelling use cases of Handshake is to have access to domain names that are uncensorable and decentralized. This would create a very healthy alternative to the current DNS paradigm. In looking into Handshake the two immediate things that I was interested in was searching which names were available to be registered, and what the DNS records were for registered name.
Namebase allows for searching, and registering domain names on the Handshake network, but I didn’t see a neat way to see the DNS records of the previously registered names. So I thought it would be kind of fun to write a bot that would allow a user to lookup names on the network and see their DNS records. If a name wasn’t registered, the the bot would return a message saying as much. And it looked like Namebase offered a very handy API to do this.
Unfortunately I kept getting an error when I tried to call the domain endpoint:
data: {
code: 'REQUEST_NOT_DOMAIN_OWNER',
message: 'You must own "nb" to access its dns settings.'
}and it appears as though the caller had to be the owner of the domain being queried. If only the owner could look up a DNS resource the bot wouldn’t be very useful. The project just got more complicated.
I was hoping there would be a public API that essentially offered a bridge to the Handshake network, something similar to what infura does for Ethereum. Unfortunately it didn’t seems as though there was such a bridge, and the domain enpoint from Namebase wasn’t going to provide the information needed for the bot.
I still thought it would be fun to make a bot to look up information on the Handshake network, but it was looking like I would have to make a bridge.
After some research into the API documentaion for hsd the reference implementation of the Handshake network, it looked as though I would need to run a node in conjunction with the bot service to access network information like DNS records.
A helpful hacker in the Discord pointed me to an API on the hsd node that would be helpful for the DNS resource, and I had already found the getnameinfo API which would provide information for queried names on the network. If this solution were to work, the next phase would be to build the bot, and run it against a local build of the hsd daemon.
Telegram bots are very approachable to create, and the available packages take a lot of headache out of the integration. It is a great platform choice for bots, as there are many helpful examples and telegram is a widely available app. The HandyDNS_Bot was designed to search for names queried by the user, and return the information from the hsd node.
The bot implementation for NodeJS is done by instantiating the node-telegram-bot-api package:
const TelegramBot = require('node-telegram-bot-api');and creating a new bot from this:
const bot = new TelegramBot(token, {polling: true});which allows the service to retrieve messages from users sending requests to the bot from telegram.
Subscribing to the message event gives access to the chat id and text sent from a user:
bot.on('message', async (msg) => {
...The rest of the bot implementation is filtering user commands, and returning queries from the hsd node to the user. The bot is effectively an interface for hsd RPC calls. The available commands on the bot are:
for example sending /name:nb to the bot will return:
name: nb
name hash:
b92ad996982b44fbea27d833c52e3fb0d6192d63835a13c61dfeb0126e2ee2ef
owner:
e5392620f0a96cfd3564e05117d07c7cb74e453d2ebf2cb5051704cc21bce98f
state: CLOSED
height: 5044
renewal: 7242
value: 50000000000
registered: true
expired: false
days until expired: 571.3
DNS:
type: GLUE4
ns: ns1.nb.
address: 44.231.6.183
type: NS
ns: ns1.nb.which comes from the hsd daemon.
Once all this was working, the last challenge was putting it in a production environment by running it on a cloud server, and making it a high-availability service.
The bot is implemented with NodeJS and runs on an Ubuntu 18.04 server with PM2 managing the bot service and the hsd daemon. Spinning up a server is always a bit a time consuming task, unless there is a handy snapshot available. I did not have anything handy, but knew that a live app is far more compelling that a github repo, so I spun one up, and began the process of building a solution for the HandyDNS_Bot.
I was dreading the task of getting the hsd node running on an Ubuntu server. I have ran many node clients from other blockchain projects, and the build always presents a challenge. It rarely is easy, and never works on initial install. I was pleasantly surprised that hnd was realtively easy to get up and running on an Ubuntu machine, as well as how painless it was to integrate the daemon with a NodeJS service. The bot and hsd daemon talked to eachother seemlessly. The only hiccup in building the hsd node was that the new machine did not have the build-essential package, in which the build failed due to make being unavailable. Once the build was sorted, everything else was what one would expect from running NodeJS application services.
The server was spun, iptables configured, updates updated, node installed, hsd built, pm2 installed, code uploaded, and then the services started. All of that went well, and the bot is live!
Photo by Guille Álvarez on Unsplash
Feel free to try it out at HandyDNS_Bot on telegram. I will leave to server up for a bit, but eventually I will have to spin it down due to the cost of the cloud instance. The project is up at handybot if anyone would like to take a look at the implementation.
It was quite fun to dig in and learn a bit more about Handshake. Thanks to the hackathon organizers for the opporunity to play.
That’s it for now.
disclaimer: these musings are offered, at best, as educational, and at worst for entertainment purposes. Do not take action on the descriptions above, as they contain risks, and are not intended as financial advice. Do not do anything above.
