Reactions & Reposts

Reactions are kind 7 events whose content is an emoji, + for a like, or - for a dislike (NIP-25). They tag the reacted-to event with e (or a for addressable events) and its author with p. Reposts share an event with your followers: kind 6 for notes and kind 16 for every other kind (NIP-18).

Reading reactions

store.reactions(event) returns the reactions to an event, including every version of an addressable event. Note, Article, Comment, Share, and Torrent casts expose the same list as reactions$.

const reactions = use$(note.reactions$);

reaction.content; // "+" when empty
reaction.emoji; // custom emoji { shortcode, url } for ":shortcode:" content
reaction.reactedPointer; // address pointer, or event pointer
const target = use$(reaction.reactedTo$);

store.reactions() is shorthand for store.model(ReactionsModel, event) and returns raw events, so pipe it through castTimelineStream(Reaction, store) to cast them.

Loading reactions from relays

Models only read the store. Use the reactions loader to fetch reactions for an event, which queries #e for regular events and #a for addressable ones.

reactionsLoader(note.event).subscribe((event) => store.add(event));

Reacting to an event

ReactionFactory tags the event, its author, its kind, and its address when addressable. Pass an Emoji object to react with a custom emoji, which also adds the emoji tag.

const like = await ReactionFactory.like(note.event).sign(signer);
const fire = await ReactionFactory.create(note.event, "🔥").sign(signer);
const custom = await ReactionFactory.create(note.event, { shortcode: "wave", url }).sign(signer);

Reading reposts

The Share cast reads either kind of repost. note.shares$ and stream.shares$ return the reposts of an event, backed by SharesModel.

share.sharedKind; // kind of the shared event
share.sharedPointer; // address pointer, or event pointer
share.embedded; // the shared event from the content, when present and verified
const shared = use$(share.shared$);

Reposting an event

ShareFactory.create() picks kind 6 or 16 from the shared event's kind, embeds the event in the content, and adds the reference tags.

const repost = await ShareFactory.create(note.event).sign(signer);

Helpers

• getReactionEventPointer(event) and getReactionAddressPointer(event) read the reacted-to event from the first e or a tag, with author and relay hints from the p tag
• getReactionEmoji(event) returns the custom emoji for a :shortcode: reaction
• getSharedEventPointer, getSharedAddressPointer, and getEmbededSharedEvent read reposts, and isValidShare validates them

Example: Reactions timeline

Best Practices

• Count + and empty reactions as likes and - as dislikes, and render other content as an emoji
• Render custom emojis from reaction.emoji, since the content is only a :shortcode:
• Prefer share.embedded before loading shared$, since it avoids a relay request