Add DVM package

README.md

@@ -9,3 +9,4 @@ This is a monorepo which is split into several different packages:
 - [@welshman/net](./packages/net) - framework for interacting with relays.
 - [@welshman/content](./packages/content) - utilities for parsing and rendering notes.
 - [@welshman/feeds](./packages/feeds) - an interpreter for custom nostr feeds.
+- [@welshman/dvm](./packages/dvm) - utilities for creating and making request against dvms.

package-lock.json

@@ -541,6 +541,10 @@
       "resolved": "packages/content",
       "link": true
     },
+    "node_modules/@welshman/dvm": {
+      "resolved": "packages/dvm",
+      "link": true
+    },
     "node_modules/@welshman/feeds": {
       "resolved": "packages/feeds",
       "link": true
@@ -2996,8 +3000,9 @@
       }
     },
     "node_modules/ws": {
-      "version": "8.16.0",
-      "license": "MIT",
+      "version": "8.17.1",
+      "resolved": "https://registry.npmjs.org/ws/-/ws-8.17.1.tgz",
+      "integrity": "sha512-6XQFvXTkbfUOZOKKILFG1PDK2NDQs4azKQl26T0YS5CxqWLgXajbPZ+h4gZekJyRqFU8pvnbAbbs/3TgRPy+GQ==",
       "engines": {
         "node": ">=10.0.0"
       },
@@ -3085,6 +3090,22 @@
         "typescript": "~5.1.6"
       }
     },
+    "packages/dvm": {
+      "name": "@welshman/dvm",
+      "version": "0.0.1",
+      "license": "MIT",
+      "dependencies": {
+        "@welshman/lib": "0.0.11",
+        "@welshman/net": "0.0.14",
+        "@welshman/util": "0.0.16",
+        "nostr-tools": "^2.7.0"
+      },
+      "devDependencies": {
+        "gts": "^5.0.1",
+        "tsc-multi": "^1.1.0",
+        "typescript": "~5.1.6"
+      }
+    },
     "packages/feeds": {
       "name": "@welshman/feeds",
       "version": "0.0.12",
@@ -3100,7 +3121,7 @@
     },
     "packages/lib": {
       "name": "@welshman/lib",
-      "version": "0.0.10",
+      "version": "0.0.11",
       "license": "MIT",
       "dependencies": {
         "@scure/base": "^1.1.6",
@@ -3127,7 +3148,7 @@
       "version": "0.0.14",
       "license": "MIT",
       "dependencies": {
-        "@welshman/lib": "0.0.10",
+        "@welshman/lib": "0.0.11",
         "@welshman/util": "0.0.16",
         "isomorphic-ws": "^5.0.0",
         "ws": "^8.16.0"
@@ -3143,7 +3164,7 @@
       "version": "0.0.16",
       "license": "MIT",
       "dependencies": {
-        "@welshman/lib": "0.0.10",
+        "@welshman/lib": "0.0.11",
         "nostr-tools": "^2.3.2"
       },
       "devDependencies": {

packages/dvm/.eslintignore

@@ -0,0 +1,2 @@
+build
+normalize-url

packages/dvm/README.md

@@ -0,0 +1,89 @@
+# @welshman/dvm [![version](https://badgen.net/npm/v/@welshman/dvm)](https://npmjs.com/package/@welshman/dvm)
+
+Utilities for building nostr DVMs.
+
+# Request example
+
+```javascript
+import type {Publish, Subscription} from '@welshman/net'
+import {makeDvmRequest, DVMEvent} from '@welshman/dvm'
+
+const req = makeDvmRequest({
+  // Create and sign a dvm request event, including any desired tags
+  event: createAndSign({kind: 5300}),
+  // Publish and subscribe to these relays
+  relays: ['wss://relay.damus.io', 'wss://dvms.f7z.io'],
+  // Timeout defaults to 30 seconds
+  timeout: 30_000,
+  // Auto close on first result (defaults to true)
+  autoClose: true,
+  // Listen for and emit `progress` events
+  reportProgress: true,
+})
+
+// Listen for progress, result, etc
+req.emitter.on(DVMEvent.Progress, (url, event) => console.log(event))
+req.emitter.on(DVMEvent.Result, (url, event) => console.log(event))
+```
+
+# Handler example
+
+```javascript
+const {bytesToHex} = require('@noble/hashes/utils')
+const {generateSecretKey} = require('nostr-tools')
+const {createEvent} = require('@welshman/util')
+const {subscribe} = require('@welshman/net')
+const {DVM} = require('@welshman/dvm')
+
+// Your DVM's private key. Store this somewhere safe
+// const hexPrivateKey = bytesToHex(generateSecretKey())
+const hexPrivateKey = '9cd387a3aa0c1abc2ef517c8402f29c069b4174e02a426491aec7566501bee67'
+
+// Tags that we'll return as content discovery suggestions
+const tags = []
+
+// Populate the tags with music by Ainsley Costello
+const sub = subscribe({
+  timeout: 30_000,
+  relays: ["wss://relay.wavlake.com"],
+  filters: [{
+    kinds: [31337],
+    '#p': ['8806372af51515bf4aef807291b96487ea1826c966a5596bca86697b5d8b23bc'],
+  }],
+})
+
+// Push event ids to our suggestions
+sub.emitter.on('event', (url, e) => tags.push(["e", e.id, url]))
+
+const dvm = new DVM({
+  // The private key used to sign events
+  sk: hexPrivateKey,
+  // Relays that the DVM will listen on
+  relays: ['wss://relay.damus.io', 'wss://dvms.f7z.io'],
+  // Only listen to requests tagging our dvm
+  requireMention: true,
+  // Expire results after 1 hour (the default)
+  expireAfter: 60 * 60,
+  // Handlers for various kinds
+  handlers: {
+    5300: dvm => ({
+      handleEvent: async function* (event) {
+        // DVM responses are stringified into the content
+        const content = JSON.stringify(tags)
+
+        // Yield our response. Kind 7000 can be used for partial results too
+        yield createEvent(event.kind + 1000, {content})
+      },
+    }),
+  }
+})
+
+// Enable logging
+dvm.logEvents = true
+
+// When you're ready
+dvm.start()
+
+// When you're done
+dvm.stop()
+```

packages/dvm/package.json

@@ -0,0 +1,39 @@
+{
+  "name": "@welshman/dvm",
+  "version": "0.0.1",
+  "author": "hodlbod",
+  "license": "MIT",
+  "description": "A collection of utilities for building nostr DVMs.",
+  "publishConfig": {
+    "access": "public"
+  },
+  "type": "module",
+  "files": [
+    "build"
+  ],
+  "types": "./build/src/index.d.ts",
+  "exports": {
+    ".": {
+      "types": "./build/src/index.d.ts",
+      "import": "./build/src/index.mjs",
+      "require": "./build/src/index.cjs"
+    }
+  },
+  "scripts": {
+    "pub": "npm run lint && npm run build && npm publish",
+    "build": "gts clean && tsc-multi",
+    "lint": "gts lint",
+    "fix": "gts fix"
+  },
+  "devDependencies": {
+    "gts": "^5.0.1",
+    "tsc-multi": "^1.1.0",
+    "typescript": "~5.1.6"
+  },
+  "dependencies": {
+    "@welshman/lib": "0.0.11",
+    "@welshman/net": "0.0.14",
+    "@welshman/util": "0.0.16",
+    "nostr-tools": "^2.7.0"
+  }
+}

packages/dvm/src/handler.ts

@@ -0,0 +1,120 @@
+import {hexToBytes} from '@noble/hashes/utils'
+import {getPublicKey, finalizeEvent} from 'nostr-tools'
+import {now} from '@welshman/lib'
+import type {TrustedEvent, EventTemplate, Filter} from '@welshman/util'
+import {subscribe, publish} from '@welshman/net'
+
+export type DVMHandler = {
+  stop?: () => void
+  handleEvent: (e: TrustedEvent) => AsyncGenerator<EventTemplate>
+}
+
+export type CreateDVMHandler = (dvm: DVM) => DVMHandler
+
+export type DVMOpts = {
+  sk: string
+  relays: string[]
+  handlers: Record<string, CreateDVMHandler>
+  expireAfter?: number
+  requireMention?: boolean
+}
+
+export class DVM {
+  active = false
+  logEvents = false
+  seen = new Set()
+  handlers = new Map()
+
+  constructor(readonly opts: DVMOpts) {
+    for (const [kind, createHandler] of Object.entries(this.opts.handlers)) {
+      this.handlers.set(parseInt(kind), createHandler(this))
+    }
+  }
+
+  async start() {
+    this.active = true
+
+    const {sk, relays, requireMention = false} = this.opts
+
+    while (this.active) {
+      await new Promise<void>(resolve => {
+        const since = now()
+        const kinds = Array.from(this.handlers.keys())
+        const filter: Filter = {kinds, since}
+
+        if (requireMention) {
+          filter['#p'] = [getPublicKey(hexToBytes(sk))]
+        }
+
+        const filters = [filter]
+        const sub = subscribe({relays, filters})
+
+        sub.emitter.on('event', (url: string, e: TrustedEvent) => this.onEvent(e))
+        sub.emitter.on('complete', () => resolve())
+      })
+    }
+  }
+
+  stop() {
+    for (const handler of this.handlers.values()) {
+      handler.stop?.()
+    }
+
+    this.active = false
+  }
+
+  async onEvent(request: TrustedEvent) {
+    console.log(request)
+    const {expireAfter = 60 * 60} = this.opts
+
+    if (this.seen.has(request.id)) {
+      return
+    }
+
+    const handler = this.handlers.get(request.kind)
+
+    if (!handler) {
+      return
+    }
+
+    this.seen.add(request.id)
+
+    if (this.logEvents) {
+      console.info('Handling request', request)
+    }
+
+    for await (const event of handler.handleEvent(request)) {
+      if (event.kind !== 7000) {
+        event.tags.push(['request', JSON.stringify(request)])
+
+        const inputTag = request.tags.find(t => t[0] === 'i')
+
+        if (inputTag) {
+          event.tags.push(inputTag)
+        }
+      }
+
+      event.tags.push(['p', request.pubkey])
+      event.tags.push(['e', request.id])
+
+      if (expireAfter) {
+        event.tags.push(['expiration', String(now() + expireAfter)])
+      }
+
+      if (this.logEvents) {
+        console.info('Publishing event', event)
+      }
+
+      this.publish(event)
+    }
+  }
+
+  async publish(template: EventTemplate) {
+    const {sk, relays} = this.opts
+    const event = finalizeEvent(template, hexToBytes(sk))
+
+    await new Promise<void>(resolve => {
+      publish({event, relays}).emitter.on('success', () => resolve())
+    })
+  }
+}

packages/dvm/src/index.ts

@@ -0,0 +1,2 @@
+export * from './handler'
+export * from './request'

packages/dvm/src/request.ts

@@ -0,0 +1,47 @@
+import {Emitter, now} from '@welshman/lib'
+import type {TrustedEvent, SignedEvent} from '@welshman/util'
+import {subscribe, publish} from '@welshman/net'
+import type {Subscription, Publish} from '@welshman/net'
+
+export enum DVMEvent {
+  Progress = "progress",
+  Result = "result",
+}
+
+export type DVMRequestOptions = {
+  event: SignedEvent
+  relays: string[]
+  timeout?: number
+  autoClose?: boolean
+  reportProgress?: boolean
+}
+
+export type DVMRequest = DVMRequestOptions & {
+  emitter: Emitter,
+  sub: Subscription
+  pub: Publish
+}
+
+export const makeDvmRequest = (request: DVMRequest) => {
+  const emitter = new Emitter()
+  const {event, relays, timeout = 30_000, autoClose = true, reportProgress = true} = request
+  const kind = event.kind + 1000
+  const kinds = reportProgress ? [kind, 7000] : [kind]
+  const filters = [{kinds, since: now() - 60, "#e": [event.id]}]
+  const sub = subscribe({relays, timeout, filters})
+  const pub = publish({event, relays, timeout})
+
+  sub.emitter.on('event', (url: string, event: TrustedEvent) => {
+    if (event.kind === 7000) {
+      emitter.emit(DVMEvent.Progress, url, event)
+    } else {
+      emitter.emit(DVMEvent.Result, url, event)
+
+      if (autoClose) {
+        sub.close()
+      }
+    }
+  })
+
+  return {request, emitter, sub, pub}
+}

packages/dvm/tsc-multi.json

@@ -0,0 +1,7 @@
+{
+  "targets": [
+    {"extname": ".cjs", "module": "commonjs"},
+    {"extname": ".mjs", "module": "esnext", "moduleResolution": "node"}
+  ],
+  "projects": ["tsconfig.json"]
+}

packages/dvm/tsconfig.json

@@ -0,0 +1,11 @@
+{
+  "extends": "../../node_modules/gts/tsconfig-google.json",
+  "compilerOptions": {
+    "rootDir": ".",
+    "outDir": "build",
+    "esModuleInterop": true,
+    "skipLibCheck": true,
+    "lib": ["esnext", "dom", "dom.iterable"]
+  },
+  "include": ["**/*.ts"]
+}

packages/lib/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@welshman/lib",
-  "version": "0.0.10",
+  "version": "0.0.11",
   "author": "hodlbod",
   "license": "MIT",
   "description": "A collection of utilities.",

packages/net/package.json

@@ -31,7 +31,7 @@
     "typescript": "~5.1.6"
   },
   "dependencies": {
-    "@welshman/lib": "0.0.10",
+    "@welshman/lib": "0.0.11",
     "@welshman/util": "0.0.16",
     "isomorphic-ws": "^5.0.0",
     "ws": "^8.16.0"

packages/util/package.json

@@ -31,7 +31,7 @@
     "typescript": "~5.1.6"
   },
   "dependencies": {
-    "@welshman/lib": "0.0.10",
+    "@welshman/lib": "0.0.11",
     "nostr-tools": "^2.3.2"
   }
 }