From 2fbcfc59a10f9c9c04f7e25606c3630f81da7235 Mon Sep 17 00:00:00 2001
From: Jon Staab <shtaab@gmail.com>
Date: Thu, 21 Nov 2024 16:03:34 -0800
Subject: [PATCH] Remove nostr-wasm, add event validation sampling

---
 package-lock.json           |  6 +++---
 packages/lib/src/Tools.ts   |  2 +-
 packages/net/src/Context.ts | 27 ++++++++++++++++++++++++---
 packages/util/package.json  |  3 +--
 packages/util/src/Events.ts |  9 +--------
 5 files changed, 30 insertions(+), 17 deletions(-)

diff --git a/package-lock.json b/package-lock.json
index 4843f1b..d8bf691 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -2487,7 +2487,8 @@
       "version": "0.1.0",
       "resolved": "https://registry.npmjs.org/nostr-wasm/-/nostr-wasm-0.1.0.tgz",
       "integrity": "sha512-78BTryCLcLYv96ONU8Ws3Q1JzjlAt+43pWQhIl86xZmWeegYCNLPml7yQ+gG3vR6V5h4XGj+TxO+SS5dsThQIA==",
-      "license": "MIT"
+      "license": "MIT",
+      "optional": true
     },
     "node_modules/npm-run-path": {
       "version": "4.0.1",
@@ -3782,8 +3783,7 @@
       "license": "MIT",
       "dependencies": {
         "@welshman/lib": "~0.0.25",
-        "nostr-tools": "^2.7.2",
-        "nostr-wasm": "^0.1.0"
+        "nostr-tools": "^2.7.2"
       },
       "devDependencies": {
         "gts": "^5.0.1",
diff --git a/packages/lib/src/Tools.ts b/packages/lib/src/Tools.ts
index 0866a0b..b3fec8e 100644
--- a/packages/lib/src/Tools.ts
+++ b/packages/lib/src/Tools.ts
@@ -127,7 +127,7 @@ export const mergeRight = <T extends Record<string, any>>(a: T, b: T) => ({...a,
 
 export const between = ([low, high]: [number, number], n: number) => n > low && n < high
 
-export const randomInt = (min = 0, max = 9) => min + Math.round(Math.random()) * (max - min)
+export const randomInt = (min = 0, max = 9) => min + Math.round(Math.random() * (max - min))
 
 export const randomId = (): string => Math.random().toString().slice(2)
 
diff --git a/packages/net/src/Context.ts b/packages/net/src/Context.ts
index dd53133..276e06b 100644
--- a/packages/net/src/Context.ts
+++ b/packages/net/src/Context.ts
@@ -1,5 +1,5 @@
-import {ctx, uniq, noop, always} from '@welshman/lib'
-import {matchFilters, unionFilters, isSignedEvent, hasValidSignature} from '@welshman/util'
+import {ctx, randomInt, uniq, noop, always} from '@welshman/lib'
+import {LOCAL_RELAY_URL, matchFilters, unionFilters, isSignedEvent, hasValidSignature} from '@welshman/util'
 import type {StampedEvent, SignedEvent, Filter, TrustedEvent} from '@welshman/util'
 import {Pool} from "./Pool"
 import {Executor} from "./Executor"
@@ -28,13 +28,34 @@ export const defaultOptimizeSubscriptions = (subs: Subscription[]) =>
       return {relays: [relay], filters}
     })
 
+export const eventValidationScores = new Map<string, number>()
+
+export const isEventValid = (url: string, event: TrustedEvent) => {
+  if (url === LOCAL_RELAY_URL) return true
+
+  const validCount = eventValidationScores.get(url) || 0
+
+  // The more events we've actually validated from this relay, the more we can trust it.
+  if (validCount > randomInt(100, 1000)) true
+
+  const isValid = isSignedEvent(event) && hasValidSignature(event)
+
+  // If the event was valid, increase the relay's score. If not, reset it
+  // Never validate less than 10% to make sure we're never totally checking out
+  if (!isValid || validCount < 900) {
+    eventValidationScores.set(url, isValid ? validCount + 1 : 0)
+  }
+
+  return isValid
+}
+
 export const getDefaultNetContext = (overrides: Partial<NetContext> = {}) => ({
   pool: new Pool(),
   authMode: AuthMode.Implicit,
   onEvent: noop,
   signEvent: noop,
   isDeleted: always(false),
-  isValid: (url: string, event: TrustedEvent) => isSignedEvent(event) && hasValidSignature(event),
+  isValid: isEventValid,
   getExecutor: (relays: string[]) => new Executor(new Relays(relays.map((relay: string) => ctx.net.pool.get(relay)))),
   matchFilters: (url: string, filters: Filter[], event: TrustedEvent) => matchFilters(filters, event),
   optimizeSubscriptions: defaultOptimizeSubscriptions,
diff --git a/packages/util/package.json b/packages/util/package.json
index 4349c4d..868604a 100644
--- a/packages/util/package.json
+++ b/packages/util/package.json
@@ -32,7 +32,6 @@
   },
   "dependencies": {
     "@welshman/lib": "~0.0.25",
-    "nostr-tools": "^2.7.2",
-    "nostr-wasm": "^0.1.0"
+    "nostr-tools": "^2.7.2"
   }
 }
diff --git a/packages/util/src/Events.ts b/packages/util/src/Events.ts
index 9066e30..4e01252 100644
--- a/packages/util/src/Events.ts
+++ b/packages/util/src/Events.ts
@@ -1,16 +1,9 @@
-import {initNostrWasm, type Nostr} from 'nostr-wasm'
 import {verifiedSymbol, getEventHash, verifyEvent} from 'nostr-tools'
 import {cached, pick, now} from '@welshman/lib'
 import {Tags} from './Tags'
 import {getAddress} from './Address'
 import {isEphemeralKind, isReplaceableKind, isPlainReplaceableKind, isParameterizedReplaceableKind} from './Kinds'
 
-let nw: Nostr
-
-initNostrWasm().then(nostrWasm => {
-  nw = nostrWasm
-})
-
 export type EventContent = {
   tags: string[][]
   content: string
@@ -109,7 +102,7 @@ const _hasValidSignature = cached<string, boolean, [SignedEvent]>({
   },
   getValue: ([e]: [SignedEvent]) => {
     try {
-      nw ? nw.verifyEvent(e) : verifyEvent(e)
+      verifyEvent(e)
     } catch (err) {
       return false
     }