feat: add nodeinfo support (#347)

Thank you!

src/handlers/request-handlers/nodeinfo-handler.ts

@@ -0,0 +1,40 @@
+import { NextFunction, Request, Response } from 'express'
+import packageJson from '../../../package.json'
+
+export const nodeinfoHandler = (req: Request, res: Response, next: NextFunction) => {
+  res.json({
+    links: [{
+      rel: 'http://nodeinfo.diaspora.software/ns/schema/2.0',
+      href: `https://${req.hostname}/nodeinfo/2.0`,
+    }, {
+      rel: 'http://nodeinfo.diaspora.software/ns/schema/2.1',
+      href: `https://${req.hostname}/nodeinfo/2.1`,
+    }],
+  }).send()
+  next()
+}
+
+export const nodeinfo21Handler = (_req: Request, res: Response, next: NextFunction) => {
+  res.json({
+    version: '2.1',
+    software: {
+      name: 'nostream',
+      version: packageJson.version,
+      repository: packageJson.repository.url,
+      homepage: packageJson.homepage,
+    },
+    protocols: ['nostr'],
+    services: {
+      inbound: [],
+      outbound: [],
+    },
+    openRegistrations: true,
+    usage: {
+      users: {},
+    },
+    metadata: {
+      features: ['nostr_relay'],
+    },
+  }).send()
+  next()
+}

src/routes/index.ts

@@ -1,5 +1,6 @@
 import express from 'express'
 
+import { nodeinfo21Handler, nodeinfoHandler } from '../handlers/request-handlers/nodeinfo-handler'
 import callbacksRouter from './callbacks'
 import { getHealthRequestHandler } from '../handlers/request-handlers/get-health-request-handler'
 import { getTermsRequestHandler } from '../handlers/request-handlers/get-terms-request-handler'
@@ -13,6 +14,10 @@ router.get('/', rootRequestHandler)
 router.get('/healthz', getHealthRequestHandler)
 router.get('/terms', getTermsRequestHandler)
 
+router.get('/.well-known/nodeinfo', nodeinfoHandler)
+router.get('/nodeinfo/2.1', nodeinfo21Handler)
+router.get('/nodeinfo/2.0', nodeinfo21Handler)
+
 router.use('/invoices', rateLimiterMiddleware, invoiceRouter)
 router.use('/callbacks', rateLimiterMiddleware, callbacksRouter)