@fedify/vocab: ActivityPub vocabulary for Fedify

This package provides a collection of type-safe objects that represent the Activity Vocabulary and vendor-specific extensions for the Fedify framework. It is the core vocabulary library that powers ActivityPub object handling in Fedify applications.

Features

• Type-safe objects for Activity Vocabulary types (Create, Note, Person, etc.)
• Vendor-specific extensions (Mastodon, Misskey, etc.)
• JSON-LD serialization and deserialization
• Immutable object design with clone() method for modifications
• Support for looking up remote objects
• Actor handle resolution via WebFinger

Installation

deno add jsr:@fedify/vocab # Deno
npm add @fedify/vocab # npm
pnpm add @fedify/vocab # pnpm
yarn add @fedify/vocab # Yarn
bun add @fedify/vocab # Bun

Usage

Instantiation

You can instantiate an object by calling the constructor with properties:

import { Create, Note } from "@fedify/vocab";

const create = new Create({
  id: new URL("https://example.com/activities/123"),
  actor: new URL("https://example.com/users/alice"),
  object: new Note({
    id: new URL("https://example.com/notes/456"),
    content: "Hello, world!",
  }),
});

JSON-LD serialization

Deserialize from JSON-LD:

import { Create } from "@fedify/vocab";

const create = await Create.fromJsonLd({
  "@context": "https://www.w3.org/ns/activitystreams",
  "type": "Create",
  "id": "https://example.com/activities/123",
  "actor": "https://example.com/users/alice",
  "object": {
    "type": "Note",
    "id": "https://example.com/notes/456",
    "content": "Hello, world!",
  }
});

Serialize to JSON-LD:

const jsonLd = await create.toJsonLd();

Immutability

All objects are immutable. Use clone() to create modified copies:

import { Note } from "@fedify/vocab";
import { LanguageString } from "@fedify/vocab-runtime";

const noteInEnglish = new Note({
  id: new URL("https://example.com/notes/123"),
  content: new LanguageString("Hello, world!", "en"),
});

const noteInChinese = noteInEnglish.clone({
  content: new LanguageString("你好，世界！", "zh"),
});

Looking up remote objects

import { lookupObject } from "@fedify/vocab";

const object = await lookupObject("https://example.com/users/alice");

Documentation

For comprehensive documentation, please refer to:

• Vocabulary documentation
• API reference

Related packages

• @fedify/fedify: The main Fedify framework
• @fedify/vocab-runtime: Runtime utilities for vocabulary objects
• @fedify/vocab-tools: Code generation tools for Activity Vocabulary

License

MIT License