PeerTube/server/helpers/activitypub.ts

import * as Bluebird from 'bluebird'
import validator from 'validator'
import { ResultList } from '../../shared/models'
import { Activity } from '../../shared/models/activitypub'
import { ACTIVITY_PUB, REMOTE_SCHEME } from '../initializers/constants'
import { signJsonLDObject } from './peertube-crypto'
import { pageToStartAndCount } from './core-utils'
import { URL } from 'url'
import { MActor, MVideoAccountLight } from '../typings/models'

export type ContextType = 'All' | 'View' | 'Announce'

function activityPubContextify <T> (data: T, type: ContextType = 'All') {
  const base = {
    RsaSignature2017: 'https://w3id.org/security#RsaSignature2017'
  }

  if (type === 'All') {
    Object.assign(base, {
      pt: 'https://joinpeertube.org/ns#',
      sc: 'http://schema.org#',
      Hashtag: 'as:Hashtag',
      uuid: 'sc:identifier',
      category: 'sc:category',
      licence: 'sc:license',
      subtitleLanguage: 'sc:subtitleLanguage',
      sensitive: 'as:sensitive',
      language: 'sc:inLanguage',
      expires: 'sc:expires',
      CacheFile: 'pt:CacheFile',
      Infohash: 'pt:Infohash',
      originallyPublishedAt: 'sc:datePublished',
      views: {
        '@type': 'sc:Number',
        '@id': 'pt:views'
      },
      state: {
        '@type': 'sc:Number',
        '@id': 'pt:state'
      },
      size: {
        '@type': 'sc:Number',
        '@id': 'pt:size'
      },
      fps: {
        '@type': 'sc:Number',
        '@id': 'pt:fps'
      },
      startTimestamp: {
        '@type': 'sc:Number',
        '@id': 'pt:startTimestamp'
      },
      stopTimestamp: {
        '@type': 'sc:Number',
        '@id': 'pt:stopTimestamp'
      },
      position: {
        '@type': 'sc:Number',
        '@id': 'pt:position'
      },
      commentsEnabled: {
        '@type': 'sc:Boolean',
        '@id': 'pt:commentsEnabled'
      },
      downloadEnabled: {
        '@type': 'sc:Boolean',
        '@id': 'pt:downloadEnabled'
      },
      waitTranscoding: {
        '@type': 'sc:Boolean',
        '@id': 'pt:waitTranscoding'
      },
      support: {
        '@type': 'sc:Text',
        '@id': 'pt:support'
      },
      likes: {
        '@id': 'as:likes',
        '@type': '@id'
      },
      dislikes: {
        '@id': 'as:dislikes',
        '@type': '@id'
      },
      playlists: {
        '@id': 'pt:playlists',
        '@type': '@id'
      },
      shares: {
        '@id': 'as:shares',
        '@type': '@id'
      },
      comments: {
        '@id': 'as:comments',
        '@type': '@id'
      }
    })
  }

  return Object.assign({}, data, {
    '@context': [
      'https://www.w3.org/ns/activitystreams',
      'https://w3id.org/security/v1',
      base
    ]
  })
}

type ActivityPubCollectionPaginationHandler = (start: number, count: number) => Bluebird<ResultList<any>> | Promise<ResultList<any>>
async function activityPubCollectionPagination (
  baseUrl: string,
  handler: ActivityPubCollectionPaginationHandler,
  page?: any,
  size = ACTIVITY_PUB.COLLECTION_ITEMS_PER_PAGE
) {
  if (!page || !validator.isInt(page)) {
    // We just display the first page URL, we only need the total items
    const result = await handler(0, 1)

    return {
      id: baseUrl,
      type: 'OrderedCollectionPage',
      totalItems: result.total,
      first: baseUrl + '?page=1'
    }
  }

  const { start, count } = pageToStartAndCount(page, size)
  const result = await handler(start, count)

  let next: string | undefined
  let prev: string | undefined

  // Assert page is a number
  page = parseInt(page, 10)

  // There are more results
  if (result.total > page * size) {
    next = baseUrl + '?page=' + (page + 1)
  }

  if (page > 1) {
    prev = baseUrl + '?page=' + (page - 1)
  }

  return {
    id: baseUrl + '?page=' + page,
    type: 'OrderedCollectionPage',
    prev,
    next,
    partOf: baseUrl,
    orderedItems: result.data,
    totalItems: result.total
  }

}

function buildSignedActivity (byActor: MActor, data: Object, contextType?: ContextType) {
  const activity = activityPubContextify(data, contextType)

  return signJsonLDObject(byActor, activity) as Promise<Activity>
}

function getAPId (activity: string | { id: string }) {
  if (typeof activity === 'string') return activity

  return activity.id
}

function checkUrlsSameHost (url1: string, url2: string) {
  const idHost = new URL(url1).host
  const actorHost = new URL(url2).host

  return idHost && actorHost && idHost.toLowerCase() === actorHost.toLowerCase()
}

function buildRemoteVideoBaseUrl (video: MVideoAccountLight, path: string) {
  const host = video.VideoChannel.Account.Actor.Server.host

  return REMOTE_SCHEME.HTTP + '://' + host + path
}

// ---------------------------------------------------------------------------

export {
  checkUrlsSameHost,
  getAPId,
  activityPubContextify,
  activityPubCollectionPagination,
  buildSignedActivity,
  buildRemoteVideoBaseUrl
}