feat: add NIP-25 reactions support with schema validation for kind 7 and kind 17

Author: CKodidela

.changeset/nip-25-reactions.md

@@ -0,0 +1,5 @@
+---
+"nostream": minor
+---
+
+Add NIP-25 Reactions support for kind 7 and kind 17 events: reaction utility helpers (`isReactionEvent`, `isExternalContentReactionEvent`, `isLikeReaction`, `isDislikeReaction`, `parseReaction`), schema validation enforcing required `e` tag on kind 7 and required `k`/`i` tags on kind 17, unit tests, and integration tests.

README.md

@@ -56,6 +56,7 @@ NIPs with a relay-specific implementation are listed here.
 - [x] NIP-16: Event Treatment
 - [x] NIP-20: Command Results
 - [x] NIP-22: Event `created_at` Limits
+- [x] NIP-25: Reactions
 - [ ] NIP-26: Delegated Event Signing (REMOVED)
 - [x] NIP-28: Public Chat
 - [x] NIP-33: Parameterized Replaceable Events

package.json

@@ -18,6 +18,7 @@
     17,
     20,
     22,
+    25,
     28,
     33,
     40,

src/factories/event-strategy-factory.ts

@@ -8,7 +8,6 @@ import {
   isReplaceableEvent,
   isRequestToVanishEvent,
 } from '../utils/event'
-import { isExternalContentReactionEvent, isReactionEvent } from '../utils/nip25'
 import { DefaultEventStrategy } from '../handlers/event-strategies/default-event-strategy'
 import { DeleteEventStrategy } from '../handlers/event-strategies/delete-event-strategy'
 import { EphemeralEventStrategy } from '../handlers/event-strategies/ephemeral-event-strategy'
@@ -42,9 +41,6 @@ export const eventStrategyFactory =
       return new DeleteEventStrategy(adapter, eventRepository)
     } else if (isParameterizedReplaceableEvent(event)) {
       return new ParameterizedReplaceableEventStrategy(adapter, eventRepository)
-    } 
-    if (isReactionEvent(event) || isExternalContentReactionEvent(event)) {
-      return new DefaultEventStrategy(adapter, eventRepository)
     }
 
     return new DefaultEventStrategy(adapter, eventRepository)

src/schemas/event-schema.ts

@@ -32,16 +32,18 @@ export const eventSchema = z
   .strict()
   .superRefine((event, ctx) => {
     if (event.kind === EventKinds.REACTION) {
-      if (!event.tags.some((tag) => tag[0] === EventTags.Event)) {
+      const hasEventTag = event.tags.some((tag) => tag[0] === EventTags.Event && typeof tag[1] === 'string' && tag[1].length > 0)
+      const hasAddressTag = event.tags.some((tag) => tag[0] === EventTags.Address && typeof tag[1] === 'string' && tag[1].length > 0)
+      if (!hasEventTag && !hasAddressTag) {
         ctx.addIssue({
           code: z.ZodIssueCode.custom,
-          message: 'Reaction event (kind 7) must have at least one e tag',
+          message: 'Reaction event (kind 7) must have at least one e or a tag',
           path: ['tags'],
         })
       }
     } else if (event.kind === EventKinds.EXTERNAL_CONTENT_REACTION) {
-      const hasKTag = event.tags.some((tag) => tag[0] === EventTags.Kind)
-      const hasITag = event.tags.some((tag) => tag[0] === EventTags.Index)
+      const hasKTag = event.tags.some((tag) => tag[0] === EventTags.Kind && tag.length >= 2 && typeof tag[1] === 'string' && tag[1].length > 0)
+      const hasITag = event.tags.some((tag) => tag[0] === EventTags.Index && tag.length >= 2 && typeof tag[1] === 'string' && tag[1].length > 0)
       if (!hasKTag || !hasITag) {
         ctx.addIssue({
           code: z.ZodIssueCode.custom,

src/utils/nip25.ts

@@ -18,11 +18,13 @@ export const parseReaction = (event: Event): ReactionEntry => {
     const aTags = event.tags.filter((tag) => tag[0] === EventTags.Address)
     const kTag = event.tags.find((tag) => tag[0] === EventTags.Kind)
 
+    const kTagValue = kTag && kTag.length > 1 ? kTag[1] : undefined
+    const parsedKind = kTagValue !== undefined ? Number(kTagValue) : undefined
     return {
         targetEventId: eTags.length > 0 ? eTags[eTags.length - 1][1] : undefined,
         targetPubkey: pTags.length > 0 ? pTags[pTags.length - 1][1] : undefined,
         targetAddress: aTags.length > 0 ? aTags[aTags.length - 1][1] : undefined,
-        targetKind: kTag ? Number(kTag[1]) : undefined,
+        targetKind: parsedKind !== undefined && Number.isFinite(parsedKind) ? parsedKind : undefined,
         content: event.content,
     }
 }