Chat federation: storing chat information

server/lib/federation/storage.ts

@@ -0,0 +1,128 @@
+import type { RegisterServerOptions, MVideoFullLight, MVideoAP } from '@peertube/peertube-types'
+import type { LiveChatJSONLDAttribute } from './types'
+import { URL } from 'url'
+import * as fs from 'fs'
+import * as path from 'path'
+
+/*
+Important Note: we could store these data in database. For example by using storageManager.storeData.
+But I'm afraid there might be write concurrency issues, or performance issues.
+Indeed, Peertube storageManager stores everything in one JSON attribute on the plugin tuple.
+
+Moreover, remote instance can create many data, that will not be cleaned.
+
+So, instead of using storageManager, or using a custom DB table, we will store data in files.
+If a file exists, it means the video has a chat.
+The file itself contains the JSON LiveChatInfos object.
+*/
+
+/**
+ * This function stores remote LiveChat infos that are contained in ActivityPub objects.
+ * We store these data for remotes videos.
+ *
+ * But we also store the data for local videos, so we can know what data we send to other Peertube instances.
+ * This is not really used for now, but can help if we want, one day, to know which videos we must refresh on remote
+ * instances.
+ * @param options server options
+ * @param video video object
+ * @param liveChatInfos video ActivityPub data to read
+ * @returns void
+ */
+async function storeVideoLiveChatInfos (
+  options: RegisterServerOptions,
+  video: MVideoFullLight | MVideoAP,
+  liveChatInfos: LiveChatJSONLDAttribute
+): Promise<void> {
+  const logger = options.peertubeHelpers.logger
+
+  const remote = video.remote
+  const filePath = await _getFilePath(options, remote, video.uuid, video.url)
+  if (!filePath) {
+    logger.error('Cant compute the file path for storing liveChat infos for video ' + video.uuid)
+    return
+  }
+
+  logger.debug(`Video ${video.uuid} data should be stored in ${filePath}`)
+
+  if (!liveChatInfos) {
+    logger.debug(`${remote ? 'Remote' : 'Local'} video ${video.uuid} has no chat infos, removing if necessary`)
+    await _del(options, filePath)
+    return
+  }
+
+  logger.debug(`${remote ? 'Remote' : 'Local'} video ${video.uuid} has caht infos to store`)
+  await _store(options, filePath, liveChatInfos)
+}
+
+async function _getFilePath (
+  options: RegisterServerOptions,
+  remote: boolean,
+  uuid: string,
+  videoUrl: string
+): Promise<string | null> {
+  const logger = options.peertubeHelpers.logger
+  try {
+    // some sanitization, just in case...
+    if (!/^(\w|-)+$/.test(uuid)) {
+      logger.error(`Video uuid seems not correct: ${uuid}`)
+      return null
+    }
+
+    let subFolders: string[]
+    if (remote) {
+      const u = new URL(videoUrl)
+      const host = u.hostname
+
+      if (host.includes('..')) {
+        // to prevent exploits that could go outside the plugin data dir.
+        logger.error(`Video host seems not correct, contains ..: ${host}`)
+        return null
+      }
+      subFolders = ['remote', host]
+    } else {
+      subFolders = ['local']
+    }
+
+    return path.resolve(
+      options.peertubeHelpers.plugin.getDataDirectoryPath(),
+      'videoInfos',
+      ...subFolders,
+      uuid + '.json'
+    )
+  } catch (err) {
+    logger.error(err)
+    return null
+  }
+}
+
+async function _del (options: RegisterServerOptions, filePath: string): Promise<void> {
+  const logger = options.peertubeHelpers.logger
+  try {
+    if (!fs.existsSync(filePath)) { return }
+    logger.info('Deleting file ' + filePath)
+    fs.rmSync(filePath)
+  } catch (err) {
+    logger.error(err)
+  }
+}
+
+async function _store (options: RegisterServerOptions, filePath: string, content: any): Promise<void> {
+  const logger = options.peertubeHelpers.logger
+  try {
+    if (!fs.existsSync(filePath)) {
+      const dir = path.dirname(filePath)
+      if (!fs.existsSync(dir)) {
+        fs.mkdirSync(dir, { recursive: true })
+      }
+    }
+    await fs.promises.writeFile(filePath, JSON.stringify(content), {
+      encoding: 'utf-8'
+    })
+  } catch (err) {
+    logger.error(err)
+  }
+}
+
+export {
+  storeVideoLiveChatInfos
+}