34 files changed, 311 insertions, 241 deletions

diff --git a/server/helpers/custom-validators/accounts.ts b/server/helpers/custom-validators/accounts.ts
index 31a2de5ca..be196d2a4 100644
--- a/server/helpers/custom-validators/accounts.ts
+++ b/server/helpers/custom-validators/accounts.ts
@@ -1,7 +1,4 @@
-import * as Bluebird from 'bluebird'
-import { Response } from 'express'
 import 'express-validator'
-import { AccountModel } from '../../models/account/account'
 import { isUserDescriptionValid, isUserUsernameValid } from './users'
 import { exists } from './misc'
 
@@ -17,47 +14,10 @@ function isAccountDescriptionValid (value: string) {
   return isUserDescriptionValid(value)
 }
 
-function doesAccountIdExist (id: number, res: Response, sendNotFound = true) {
-  const promise = AccountModel.load(id)
-
-  return doesAccountExist(promise, res, sendNotFound)
-}
-
-function doesLocalAccountNameExist (name: string, res: Response, sendNotFound = true) {
-  const promise = AccountModel.loadLocalByName(name)
-
-  return doesAccountExist(promise, res, sendNotFound)
-}
-
-function doesAccountNameWithHostExist (nameWithDomain: string, res: Response, sendNotFound = true) {
-  return doesAccountExist(AccountModel.loadByNameWithHost(nameWithDomain), res, sendNotFound)
-}
-
-async function doesAccountExist (p: Bluebird<AccountModel>, res: Response, sendNotFound: boolean) {
-  const account = await p
-
-  if (!account) {
-    if (sendNotFound === true) {
-      res.status(404)
-         .send({ error: 'Account not found' })
-         .end()
-    }
-
-    return false
-  }
-
-  res.locals.account = account
-
-  return true
-}
-
 // ---------------------------------------------------------------------------
 
 export {
   isAccountIdValid,
-  doesAccountIdExist,
-  doesLocalAccountNameExist,
   isAccountDescriptionValid,
-  doesAccountNameWithHostExist,
   isAccountNameValid
 }
diff --git a/server/helpers/custom-validators/video-abuses.ts b/server/helpers/custom-validators/video-abuses.ts
index a61dcee1c..e43d12be8 100644
--- a/server/helpers/custom-validators/video-abuses.ts
+++ b/server/helpers/custom-validators/video-abuses.ts
@@ -18,25 +18,9 @@ function isVideoAbuseStateValid (value: string) {
   return exists(value) && VIDEO_ABUSE_STATES[ value ] !== undefined
 }
 
-async function doesVideoAbuseExist (abuseId: number, videoId: number, res: Response) {
-  const videoAbuse = await VideoAbuseModel.loadByIdAndVideoId(abuseId, videoId)
-
-  if (videoAbuse === null) {
-    res.status(404)
-       .json({ error: 'Video abuse not found' })
-       .end()
-
-    return false
-  }
-
-  res.locals.videoAbuse = videoAbuse
-  return true
-}
-
 // ---------------------------------------------------------------------------
 
 export {
-  doesVideoAbuseExist,
   isVideoAbuseStateValid,
   isVideoAbuseReasonValid,
   isVideoAbuseModerationCommentValid
diff --git a/server/helpers/custom-validators/video-blacklist.ts b/server/helpers/custom-validators/video-blacklist.ts
index 3743f7023..9a44332ef 100644
--- a/server/helpers/custom-validators/video-blacklist.ts
+++ b/server/helpers/custom-validators/video-blacklist.ts
@@ -1,8 +1,6 @@
-import { Response } from 'express'
 import * as validator from 'validator'
 import { exists } from './misc'
 import { CONSTRAINTS_FIELDS } from '../../initializers/constants'
-import { VideoBlacklistModel } from '../../models/video/video-blacklist'
 import { VideoBlacklistType } from '../../../shared/models/videos'
 
 const VIDEO_BLACKLIST_CONSTRAINTS_FIELDS = CONSTRAINTS_FIELDS.VIDEO_BLACKLIST
@@ -11,21 +9,6 @@ function isVideoBlacklistReasonValid (value: string) {
   return value === null || validator.isLength(value, VIDEO_BLACKLIST_CONSTRAINTS_FIELDS.REASON)
 }
 
-async function doesVideoBlacklistExist (videoId: number, res: Response) {
-  const videoBlacklist = await VideoBlacklistModel.loadByVideoId(videoId)
-
-  if (videoBlacklist === null) {
-    res.status(404)
-       .json({ error: 'Blacklisted video not found' })
-       .end()
-
-    return false
-  }
-
-  res.locals.videoBlacklist = videoBlacklist
-  return true
-}
-
 function isVideoBlacklistTypeValid (value: any) {
   return exists(value) && validator.isInt('' + value) && VideoBlacklistType[value] !== undefined
 }
@@ -34,6 +17,5 @@ function isVideoBlacklistTypeValid (value: any) {
 
 export {
   isVideoBlacklistReasonValid,
-  isVideoBlacklistTypeValid,
-  doesVideoBlacklistExist
+  isVideoBlacklistTypeValid
 }
diff --git a/server/helpers/custom-validators/video-captions.ts b/server/helpers/custom-validators/video-captions.ts
index 3b6569a8a..d06eb3695 100644
--- a/server/helpers/custom-validators/video-captions.ts
+++ b/server/helpers/custom-validators/video-captions.ts
@@ -1,8 +1,5 @@
 import { CONSTRAINTS_FIELDS, MIMETYPES, VIDEO_LANGUAGES } from '../../initializers/constants'
 import { exists, isFileValid } from './misc'
-import { Response } from 'express'
-import { VideoModel } from '../../models/video/video'
-import { VideoCaptionModel } from '../../models/video/video-caption'
 
 function isVideoCaptionLanguageValid (value: any) {
   return exists(value) && VIDEO_LANGUAGES[ value ] !== undefined
@@ -16,25 +13,9 @@ function isVideoCaptionFile (files: { [ fieldname: string ]: Express.Multer.File
   return isFileValid(files, videoCaptionTypesRegex, field, CONSTRAINTS_FIELDS.VIDEO_CAPTIONS.CAPTION_FILE.FILE_SIZE.max)
 }
 
-async function doesVideoCaptionExist (video: VideoModel, language: string, res: Response) {
-  const videoCaption = await VideoCaptionModel.loadByVideoIdAndLanguage(video.id, language)
-
-  if (!videoCaption) {
-    res.status(404)
-       .json({ error: 'Video caption not found' })
-       .end()
-
-    return false
-  }
-
-  res.locals.videoCaption = videoCaption
-  return true
-}
-
 // ---------------------------------------------------------------------------
 
 export {
   isVideoCaptionFile,
-  isVideoCaptionLanguageValid,
-  doesVideoCaptionExist
+  isVideoCaptionLanguageValid
 }
diff --git a/server/helpers/custom-validators/video-channels.ts b/server/helpers/custom-validators/video-channels.ts
index f818ce8f1..0471f6ec4 100644
--- a/server/helpers/custom-validators/video-channels.ts
+++ b/server/helpers/custom-validators/video-channels.ts
@@ -20,33 +20,12 @@ function isVideoChannelSupportValid (value: string) {
   return value === null || (exists(value) && validator.isLength(value, VIDEO_CHANNELS_CONSTRAINTS_FIELDS.SUPPORT))
 }
 
-async function doesLocalVideoChannelNameExist (name: string, res: express.Response) {
-  const videoChannel = await VideoChannelModel.loadLocalByNameAndPopulateAccount(name)
-
-  return processVideoChannelExist(videoChannel, res)
-}
-
-async function doesVideoChannelIdExist (id: number, res: express.Response) {
-  const videoChannel = await VideoChannelModel.loadAndPopulateAccount(+id)
-
-  return processVideoChannelExist(videoChannel, res)
-}
-
-async function doesVideoChannelNameWithHostExist (nameWithDomain: string, res: express.Response) {
-  const videoChannel = await VideoChannelModel.loadByNameWithHostAndPopulateAccount(nameWithDomain)
-
-  return processVideoChannelExist(videoChannel, res)
-}
-
 // ---------------------------------------------------------------------------
 
 export {
-  doesVideoChannelNameWithHostExist,
-  doesLocalVideoChannelNameExist,
   isVideoChannelDescriptionValid,
   isVideoChannelNameValid,
   isVideoChannelSupportValid,
-  doesVideoChannelIdExist
 }
 
 function processVideoChannelExist (videoChannel: VideoChannelModel, res: express.Response) {
diff --git a/server/helpers/custom-validators/video-playlists.ts b/server/helpers/custom-validators/video-playlists.ts
index 2fe426560..60125dcda 100644
--- a/server/helpers/custom-validators/video-playlists.ts
+++ b/server/helpers/custom-validators/video-playlists.ts
@@ -26,27 +26,9 @@ function isVideoPlaylistTypeValid (value: any) {
   return exists(value) && VIDEO_PLAYLIST_TYPES[ value ] !== undefined
 }
 
-async function doesVideoPlaylistExist (id: number | string, res: express.Response, fetchType: 'summary' | 'all' = 'summary') {
-  const videoPlaylist = fetchType === 'summary'
-    ? await VideoPlaylistModel.loadWithAccountAndChannelSummary(id, undefined)
-    : await VideoPlaylistModel.loadWithAccountAndChannel(id, undefined)
-
-  if (!videoPlaylist) {
-    res.status(404)
-       .json({ error: 'Video playlist not found' })
-       .end()
-
-    return false
-  }
-
-  res.locals.videoPlaylist = videoPlaylist
-  return true
-}
-
 // ---------------------------------------------------------------------------
 
 export {
-  doesVideoPlaylistExist,
   isVideoPlaylistNameValid,
   isVideoPlaylistDescriptionValid,
   isVideoPlaylistPrivacyValid,
diff --git a/server/helpers/custom-validators/videos.ts b/server/helpers/custom-validators/videos.ts
index 214db17a1..157e1a8e3 100644
--- a/server/helpers/custom-validators/videos.ts
+++ b/server/helpers/custom-validators/videos.ts
@@ -15,10 +15,8 @@ import {
 } from '../../initializers/constants'
 import { VideoModel } from '../../models/video/video'
 import { exists, isArray, isDateValid, isFileValid } from './misc'
-import { VideoChannelModel } from '../../models/video/video-channel'
 import { UserModel } from '../../models/account/user'
 import * as magnetUtil from 'magnet-uri'
-import { fetchVideo, VideoFetchType } from '../video'
 
 const VIDEOS_CONSTRAINTS_FIELDS = CONSTRAINTS_FIELDS.VIDEOS
 
@@ -143,79 +141,10 @@ function isVideoMagnetUriValid (value: string) {
   return parsed && isVideoFileInfoHashValid(parsed.infoHash)
 }
 
-function checkUserCanManageVideo (user: UserModel, video: VideoModel, right: UserRight, res: Response) {
-  // Retrieve the user who did the request
-  if (video.isOwned() === false) {
-    res.status(403)
-       .json({ error: 'Cannot manage a video of another server.' })
-       .end()
-    return false
-  }
-
-  // Check if the user can delete the video
-  // The user can delete it if he has the right
-  // Or if s/he is the video's account
-  const account = video.VideoChannel.Account
-  if (user.hasRight(right) === false && account.userId !== user.id) {
-    res.status(403)
-       .json({ error: 'Cannot manage a video of another user.' })
-       .end()
-    return false
-  }
-
-  return true
-}
-
-async function doesVideoExist (id: number | string, res: Response, fetchType: VideoFetchType = 'all') {
-  const userId = res.locals.oauth ? res.locals.oauth.token.User.id : undefined
-
-  const video = await fetchVideo(id, fetchType, userId)
-
-  if (video === null) {
-    res.status(404)
-       .json({ error: 'Video not found' })
-       .end()
-
-    return false
-  }
-
-  if (fetchType !== 'none') res.locals.video = video
-  return true
-}
-
-async function doesVideoChannelOfAccountExist (channelId: number, user: UserModel, res: Response) {
-  if (user.hasRight(UserRight.UPDATE_ANY_VIDEO) === true) {
-    const videoChannel = await VideoChannelModel.loadAndPopulateAccount(channelId)
-    if (videoChannel === null) {
-      res.status(400)
-         .json({ error: 'Unknown video `video channel` on this instance.' })
-         .end()
-
-      return false
-    }
-
-    res.locals.videoChannel = videoChannel
-    return true
-  }
-
-  const videoChannel = await VideoChannelModel.loadByIdAndAccount(channelId, user.Account.id)
-  if (videoChannel === null) {
-    res.status(400)
-       .json({ error: 'Unknown video `video channel` for this account.' })
-       .end()
-
-    return false
-  }
-
-  res.locals.videoChannel = videoChannel
-  return true
-}
-
 // ---------------------------------------------------------------------------
 
 export {
   isVideoCategoryValid,
-  checkUserCanManageVideo,
   isVideoLicenceValid,
   isVideoLanguageValid,
   isVideoTruncatedDescriptionValid,
@@ -237,9 +166,7 @@ export {
   isVideoPrivacyValid,
   isVideoFileResolutionValid,
   isVideoFileSizeValid,
-  doesVideoExist,
   isVideoImage,
-  doesVideoChannelOfAccountExist,
   isVideoSupportValid,
   isVideoFilterValid
 }
diff --git a/server/helpers/middlewares/accounts.ts b/server/helpers/middlewares/accounts.ts
new file mode 100644
index 000000000..791022b97
--- /dev/null
+++ b/server/helpers/middlewares/accounts.ts
@@ -0,0 +1,46 @@
+import { Response } from 'express'
+import { AccountModel } from '../../models/account/account'
+import * as Bluebird from 'bluebird'
+
+function doesAccountIdExist (id: number, res: Response, sendNotFound = true) {
+  const promise = AccountModel.load(id)
+
+  return doesAccountExist(promise, res, sendNotFound)
+}
+
+function doesLocalAccountNameExist (name: string, res: Response, sendNotFound = true) {
+  const promise = AccountModel.loadLocalByName(name)
+
+  return doesAccountExist(promise, res, sendNotFound)
+}
+
+function doesAccountNameWithHostExist (nameWithDomain: string, res: Response, sendNotFound = true) {
+  return doesAccountExist(AccountModel.loadByNameWithHost(nameWithDomain), res, sendNotFound)
+}
+
+async function doesAccountExist (p: Bluebird<AccountModel>, res: Response, sendNotFound: boolean) {
+  const account = await p
+
+  if (!account) {
+    if (sendNotFound === true) {
+      res.status(404)
+         .send({ error: 'Account not found' })
+         .end()
+    }
+
+    return false
+  }
+
+  res.locals.account = account
+
+  return true
+}
+
+// ---------------------------------------------------------------------------
+
+export {
+  doesAccountIdExist,
+  doesLocalAccountNameExist,
+  doesAccountNameWithHostExist,
+  doesAccountExist
+}
diff --git a/server/helpers/middlewares/index.ts b/server/helpers/middlewares/index.ts
new file mode 100644
index 000000000..f91aeaa12
--- /dev/null
+++ b/server/helpers/middlewares/index.ts
@@ -0,0 +1,7 @@
+export * from './accounts'
+export * from './video-abuses'
+export * from './video-blacklists'
+export * from './video-captions'
+export * from './video-channels'
+export * from './video-playlists'
+export * from './videos'
diff --git a/server/helpers/middlewares/video-abuses.ts b/server/helpers/middlewares/video-abuses.ts
new file mode 100644
index 000000000..b23f1f021
--- /dev/null
+++ b/server/helpers/middlewares/video-abuses.ts
@@ -0,0 +1,41 @@
+import * as express from 'express'
+import { VideoChannelModel } from '../../models/video/video-channel'
+
+async function doesLocalVideoChannelNameExist (name: string, res: express.Response) {
+  const videoChannel = await VideoChannelModel.loadLocalByNameAndPopulateAccount(name)
+
+  return processVideoChannelExist(videoChannel, res)
+}
+
+async function doesVideoChannelIdExist (id: number, res: express.Response) {
+  const videoChannel = await VideoChannelModel.loadAndPopulateAccount(+id)
+
+  return processVideoChannelExist(videoChannel, res)
+}
+
+async function doesVideoChannelNameWithHostExist (nameWithDomain: string, res: express.Response) {
+  const videoChannel = await VideoChannelModel.loadByNameWithHostAndPopulateAccount(nameWithDomain)
+
+  return processVideoChannelExist(videoChannel, res)
+}
+
+// ---------------------------------------------------------------------------
+
+export {
+  doesLocalVideoChannelNameExist,
+  doesVideoChannelIdExist,
+  doesVideoChannelNameWithHostExist
+}
+
+function processVideoChannelExist (videoChannel: VideoChannelModel, res: express.Response) {
+  if (!videoChannel) {
+    res.status(404)
+       .json({ error: 'Video channel not found' })
+       .end()
+
+    return false
+  }
+
+  res.locals.videoChannel = videoChannel
+  return true
+}
diff --git a/server/helpers/middlewares/video-blacklists.ts b/server/helpers/middlewares/video-blacklists.ts
new file mode 100644
index 000000000..c79420a0c
--- /dev/null
+++ b/server/helpers/middlewares/video-blacklists.ts
@@ -0,0 +1,23 @@
+import { Response } from 'express'
+import { VideoBlacklistModel } from '../../models/video/video-blacklist'
+
+async function doesVideoBlacklistExist (videoId: number, res: Response) {
+  const videoBlacklist = await VideoBlacklistModel.loadByVideoId(videoId)
+
+  if (videoBlacklist === null) {
+    res.status(404)
+       .json({ error: 'Blacklisted video not found' })
+       .end()
+
+    return false
+  }
+
+  res.locals.videoBlacklist = videoBlacklist
+  return true
+}
+
+// ---------------------------------------------------------------------------
+
+export {
+  doesVideoBlacklistExist
+}
diff --git a/server/helpers/middlewares/video-captions.ts b/server/helpers/middlewares/video-captions.ts
new file mode 100644
index 000000000..dc3d0144b
--- /dev/null
+++ b/server/helpers/middlewares/video-captions.ts
@@ -0,0 +1,24 @@
+import { VideoModel } from '../../models/video/video'
+import { Response } from 'express'
+import { VideoCaptionModel } from '../../models/video/video-caption'
+
+async function doesVideoCaptionExist (video: VideoModel, language: string, res: Response) {
+  const videoCaption = await VideoCaptionModel.loadByVideoIdAndLanguage(video.id, language)
+
+  if (!videoCaption) {
+    res.status(404)
+       .json({ error: 'Video caption not found' })
+       .end()
+
+    return false
+  }
+
+  res.locals.videoCaption = videoCaption
+  return true
+}
+
+// ---------------------------------------------------------------------------
+
+export {
+  doesVideoCaptionExist
+}
diff --git a/server/helpers/middlewares/video-channels.ts b/server/helpers/middlewares/video-channels.ts
new file mode 100644
index 000000000..1b573ca37
--- /dev/null
+++ b/server/helpers/middlewares/video-channels.ts
@@ -0,0 +1,23 @@
+import { Response } from 'express'
+import { VideoAbuseModel } from '../../models/video/video-abuse'
+
+async function doesVideoAbuseExist (abuseId: number, videoId: number, res: Response) {
+  const videoAbuse = await VideoAbuseModel.loadByIdAndVideoId(abuseId, videoId)
+
+  if (videoAbuse === null) {
+    res.status(404)
+       .json({ error: 'Video abuse not found' })
+       .end()
+
+    return false
+  }
+
+  res.locals.videoAbuse = videoAbuse
+  return true
+}
+
+// ---------------------------------------------------------------------------
+
+export {
+  doesVideoAbuseExist
+}
diff --git a/server/helpers/middlewares/video-playlists.ts b/server/helpers/middlewares/video-playlists.ts
new file mode 100644
index 000000000..735bf362f
--- /dev/null
+++ b/server/helpers/middlewares/video-playlists.ts
@@ -0,0 +1,25 @@
+import * as express from 'express'
+import { VideoPlaylistModel } from '../../models/video/video-playlist'
+
+async function doesVideoPlaylistExist (id: number | string, res: express.Response, fetchType: 'summary' | 'all' = 'summary') {
+  const videoPlaylist = fetchType === 'summary'
+    ? await VideoPlaylistModel.loadWithAccountAndChannelSummary(id, undefined)
+    : await VideoPlaylistModel.loadWithAccountAndChannel(id, undefined)
+
+  if (!videoPlaylist) {
+    res.status(404)
+       .json({ error: 'Video playlist not found' })
+       .end()
+
+    return false
+  }
+
+  res.locals.videoPlaylist = videoPlaylist
+  return true
+}
+
+// ---------------------------------------------------------------------------
+
+export {
+  doesVideoPlaylistExist
+}
diff --git a/server/helpers/middlewares/videos.ts b/server/helpers/middlewares/videos.ts
new file mode 100644
index 000000000..ceb1058ec
--- /dev/null
+++ b/server/helpers/middlewares/videos.ts
@@ -0,0 +1,82 @@
+import { Response } from 'express'
+import { fetchVideo, VideoFetchType } from '../video'
+import { UserModel } from '../../models/account/user'
+import { UserRight } from '../../../shared/models/users'
+import { VideoChannelModel } from '../../models/video/video-channel'
+import { VideoModel } from '../../models/video/video'
+
+async function doesVideoExist (id: number | string, res: Response, fetchType: VideoFetchType = 'all') {
+  const userId = res.locals.oauth ? res.locals.oauth.token.User.id : undefined
+
+  const video = await fetchVideo(id, fetchType, userId)
+
+  if (video === null) {
+    res.status(404)
+       .json({ error: 'Video not found' })
+       .end()
+
+    return false
+  }
+
+  if (fetchType !== 'none') res.locals.video = video
+  return true
+}
+
+async function doesVideoChannelOfAccountExist (channelId: number, user: UserModel, res: Response) {
+  if (user.hasRight(UserRight.UPDATE_ANY_VIDEO) === true) {
+    const videoChannel = await VideoChannelModel.loadAndPopulateAccount(channelId)
+    if (videoChannel === null) {
+      res.status(400)
+         .json({ error: 'Unknown video `video channel` on this instance.' })
+         .end()
+
+      return false
+    }
+
+    res.locals.videoChannel = videoChannel
+    return true
+  }
+
+  const videoChannel = await VideoChannelModel.loadByIdAndAccount(channelId, user.Account.id)
+  if (videoChannel === null) {
+    res.status(400)
+       .json({ error: 'Unknown video `video channel` for this account.' })
+       .end()
+
+    return false
+  }
+
+  res.locals.videoChannel = videoChannel
+  return true
+}
+
+function checkUserCanManageVideo (user: UserModel, video: VideoModel, right: UserRight, res: Response) {
+  // Retrieve the user who did the request
+  if (video.isOwned() === false) {
+    res.status(403)
+       .json({ error: 'Cannot manage a video of another server.' })
+       .end()
+    return false
+  }
+
+  // Check if the user can delete the video
+  // The user can delete it if he has the right
+  // Or if s/he is the video's account
+  const account = video.VideoChannel.Account
+  if (user.hasRight(right) === false && account.userId !== user.id) {
+    res.status(403)
+       .json({ error: 'Cannot manage a video of another user.' })
+       .end()
+    return false
+  }
+
+  return true
+}
+
+// ---------------------------------------------------------------------------
+
+export {
+  doesVideoChannelOfAccountExist,
+  doesVideoExist,
+  checkUserCanManageVideo
+}
diff --git a/server/lib/client-html.ts b/server/lib/client-html.ts
index 1e7897220..44bd7abb5 100644
--- a/server/lib/client-html.ts
+++ b/server/lib/client-html.ts
@@ -12,12 +12,15 @@ import { AccountModel } from '../models/account/account'
 import { VideoChannelModel } from '../models/video/video-channel'
 import * as Bluebird from 'bluebird'
 import { CONFIG } from '../initializers/config'
+import { logger } from '../helpers/logger'
 
 export class ClientHtml {
 
   private static htmlCache: { [ path: string ]: string } = {}
 
   static invalidCache () {
+    logger.info('Cleaning HTML cache.')
+
     ClientHtml.htmlCache = {}
   }
 
@@ -146,7 +149,7 @@ export class ClientHtml {
 
   private static async addAsyncPluginCSS (htmlStringPage: string) {
     const globalCSSContent = await readFile(PLUGIN_GLOBAL_CSS_PATH)
-    if (!globalCSSContent) return htmlStringPage
+    if (globalCSSContent.byteLength === 0) return htmlStringPage
 
     const fileHash = sha256(globalCSSContent)
     const linkTag = `<link rel="stylesheet" href="/plugins/global.css?hash=${fileHash}" />`
diff --git a/server/lib/plugins/plugin-manager.ts b/server/lib/plugins/plugin-manager.ts
index c0b49c7c7..a87d02c56 100644
--- a/server/lib/plugins/plugin-manager.ts
+++ b/server/lib/plugins/plugin-manager.ts
@@ -317,6 +317,8 @@ export class PluginManager implements ServerHook {
   // ###################### CSS ######################
 
   private resetCSSGlobalFile () {
+    ClientHtml.invalidCache()
+
     return outputFile(PLUGIN_GLOBAL_CSS_PATH, '')
   }
 
diff --git a/server/middlewares/validators/account.ts b/server/middlewares/validators/account.ts
index 96e120a38..67e4bf8cc 100644
--- a/server/middlewares/validators/account.ts
+++ b/server/middlewares/validators/account.ts
@@ -1,8 +1,9 @@
 import * as express from 'express'
 import { param } from 'express-validator/check'
-import { isAccountNameValid, doesAccountNameWithHostExist, doesLocalAccountNameExist } from '../../helpers/custom-validators/accounts'
+import { isAccountNameValid } from '../../helpers/custom-validators/accounts'
 import { logger } from '../../helpers/logger'
 import { areValidationErrors } from './utils'
+import { doesAccountNameWithHostExist, doesLocalAccountNameExist } from '../../helpers/middlewares'
 
 const localAccountValidator = [
   param('name').custom(isAccountNameValid).withMessage('Should have a valid account name'),
diff --git a/server/middlewares/validators/blocklist.ts b/server/middlewares/validators/blocklist.ts
index 7c494de78..63d95e9e0 100644
--- a/server/middlewares/validators/blocklist.ts
+++ b/server/middlewares/validators/blocklist.ts
@@ -2,13 +2,13 @@ import { body, param } from 'express-validator/check'
 import * as express from 'express'
 import { logger } from '../../helpers/logger'
 import { areValidationErrors } from './utils'
-import { doesAccountNameWithHostExist } from '../../helpers/custom-validators/accounts'
 import { AccountBlocklistModel } from '../../models/account/account-blocklist'
 import { isHostValid } from '../../helpers/custom-validators/servers'
 import { ServerBlocklistModel } from '../../models/server/server-blocklist'
 import { ServerModel } from '../../models/server/server'
 import { getServerActor } from '../../helpers/utils'
 import { WEBSERVER } from '../../initializers/constants'
+import { doesAccountNameWithHostExist } from '../../helpers/middlewares'
 
 const blockAccountValidator = [
   body('accountName').exists().withMessage('Should have an account name with host'),
diff --git a/server/middlewares/validators/feeds.ts b/server/middlewares/validators/feeds.ts
index dd362619d..fa130121f 100644
--- a/server/middlewares/validators/feeds.ts
+++ b/server/middlewares/validators/feeds.ts
@@ -1,12 +1,16 @@
 import * as express from 'express'
 import { param, query } from 'express-validator/check'
-import { doesAccountIdExist, doesAccountNameWithHostExist } from '../../helpers/custom-validators/accounts'
 import { isIdOrUUIDValid, isIdValid } from '../../helpers/custom-validators/misc'
 import { logger } from '../../helpers/logger'
 import { areValidationErrors } from './utils'
 import { isValidRSSFeed } from '../../helpers/custom-validators/feeds'
-import { doesVideoChannelIdExist, doesVideoChannelNameWithHostExist } from '../../helpers/custom-validators/video-channels'
-import { doesVideoExist } from '../../helpers/custom-validators/videos'
+import { doesVideoExist } from '../../helpers/middlewares/videos'
+import {
+  doesAccountIdExist,
+  doesAccountNameWithHostExist,
+  doesVideoChannelIdExist,
+  doesVideoChannelNameWithHostExist
+} from '../../helpers/middlewares'
 
 const videoFeedsValidator = [
   param('format').optional().custom(isValidRSSFeed).withMessage('Should have a valid format (rss, atom, json)'),
diff --git a/server/middlewares/validators/oembed.ts b/server/middlewares/validators/oembed.ts
index 0bb908d0b..505319980 100644
--- a/server/middlewares/validators/oembed.ts
+++ b/server/middlewares/validators/oembed.ts
@@ -3,10 +3,10 @@ import { query } from 'express-validator/check'
 import { join } from 'path'
 import { isTestInstance } from '../../helpers/core-utils'
 import { isIdOrUUIDValid } from '../../helpers/custom-validators/misc'
-import { doesVideoExist } from '../../helpers/custom-validators/videos'
 import { logger } from '../../helpers/logger'
 import { areValidationErrors } from './utils'
 import { WEBSERVER } from '../../initializers/constants'
+import { doesVideoExist } from '../../helpers/middlewares'
 
 const urlShouldStartWith = WEBSERVER.SCHEME + '://' + join(WEBSERVER.HOST, 'videos', 'watch') + '/'
 const videoWatchRegex = new RegExp('([^/]+)$')
diff --git a/server/middlewares/validators/redundancy.ts b/server/middlewares/validators/redundancy.ts
index 76cf89c40..edc53a6b2 100644
--- a/server/middlewares/validators/redundancy.ts
+++ b/server/middlewares/validators/redundancy.ts
@@ -2,12 +2,12 @@ import * as express from 'express'
 import 'express-validator'
 import { body, param } from 'express-validator/check'
 import { exists, isBooleanValid, isIdOrUUIDValid, toIntOrNull } from '../../helpers/custom-validators/misc'
-import { doesVideoExist } from '../../helpers/custom-validators/videos'
 import { logger } from '../../helpers/logger'
 import { areValidationErrors } from './utils'
 import { VideoRedundancyModel } from '../../models/redundancy/video-redundancy'
 import { isHostValid } from '../../helpers/custom-validators/servers'
 import { ServerModel } from '../../models/server/server'
+import { doesVideoExist } from '../../helpers/middlewares'
 
 const videoFileRedundancyGetValidator = [
   param('videoId').custom(isIdOrUUIDValid).not().isEmpty().withMessage('Should have a valid video id'),
diff --git a/server/middlewares/validators/users.ts b/server/middlewares/validators/users.ts
index a507afc5b..7002de20d 100644
--- a/server/middlewares/validators/users.ts
+++ b/server/middlewares/validators/users.ts
@@ -13,12 +13,12 @@ import {
   isUserNSFWPolicyValid,
   isUserPasswordValid,
   isUserRoleValid,
-  isUserUsernameValid, isUserVideoLanguages,
+  isUserUsernameValid,
+  isUserVideoLanguages,
   isUserVideoQuotaDailyValid,
   isUserVideoQuotaValid,
   isUserVideosHistoryEnabledValid
 } from '../../helpers/custom-validators/users'
-import { doesVideoExist } from '../../helpers/custom-validators/videos'
 import { logger } from '../../helpers/logger'
 import { isSignupAllowed, isSignupAllowedForCurrentIP } from '../../helpers/signup'
 import { Redis } from '../../lib/redis'
@@ -30,6 +30,7 @@ import { isVideoChannelNameValid } from '../../helpers/custom-validators/video-c
 import { UserRegister } from '../../../shared/models/users/user-register.model'
 import { isThemeNameValid } from '../../helpers/custom-validators/plugins'
 import { isThemeRegistered } from '../../lib/plugins/theme-utils'
+import { doesVideoExist } from '../../helpers/middlewares'
 
 const usersAddValidator = [
   body('username').custom(isUserUsernameValid).withMessage('Should have a valid username (lowercase alphanumeric characters)'),
diff --git a/server/middlewares/validators/videos/video-abuses.ts b/server/middlewares/validators/videos/video-abuses.ts
index d1910a992..e176e01af 100644
--- a/server/middlewares/validators/videos/video-abuses.ts
+++ b/server/middlewares/validators/videos/video-abuses.ts
@@ -2,15 +2,14 @@ import * as express from 'express'
 import 'express-validator'
 import { body, param } from 'express-validator/check'
 import { isIdOrUUIDValid, isIdValid } from '../../../helpers/custom-validators/misc'
-import { doesVideoExist } from '../../../helpers/custom-validators/videos'
 import { logger } from '../../../helpers/logger'
 import { areValidationErrors } from '../utils'
 import {
-  doesVideoAbuseExist,
   isVideoAbuseModerationCommentValid,
   isVideoAbuseReasonValid,
   isVideoAbuseStateValid
 } from '../../../helpers/custom-validators/video-abuses'
+import { doesVideoAbuseExist, doesVideoExist } from '../../../helpers/middlewares'
 
 const videoAbuseReportValidator = [
   param('videoId').custom(isIdOrUUIDValid).not().isEmpty().withMessage('Should have a valid videoId'),
diff --git a/server/middlewares/validators/videos/video-blacklist.ts b/server/middlewares/validators/videos/video-blacklist.ts
index 1d7ddb2e3..db59427c7 100644
--- a/server/middlewares/validators/videos/video-blacklist.ts
+++ b/server/middlewares/validators/videos/video-blacklist.ts
@@ -1,14 +1,10 @@
 import * as express from 'express'
 import { body, param, query } from 'express-validator/check'
 import { isBooleanValid, isIdOrUUIDValid } from '../../../helpers/custom-validators/misc'
-import { doesVideoExist } from '../../../helpers/custom-validators/videos'
 import { logger } from '../../../helpers/logger'
 import { areValidationErrors } from '../utils'
-import {
-  doesVideoBlacklistExist,
-  isVideoBlacklistReasonValid,
-  isVideoBlacklistTypeValid
-} from '../../../helpers/custom-validators/video-blacklist'
+import { isVideoBlacklistReasonValid, isVideoBlacklistTypeValid } from '../../../helpers/custom-validators/video-blacklist'
+import { doesVideoBlacklistExist, doesVideoExist } from '../../../helpers/middlewares'
 
 const videosBlacklistRemoveValidator = [
   param('videoId').custom(isIdOrUUIDValid).not().isEmpty().withMessage('Should have a valid videoId'),
diff --git a/server/middlewares/validators/videos/video-captions.ts b/server/middlewares/validators/videos/video-captions.ts
index d857ac3ec..f8739e27f 100644
--- a/server/middlewares/validators/videos/video-captions.ts
+++ b/server/middlewares/validators/videos/video-captions.ts
@@ -1,13 +1,13 @@
 import * as express from 'express'
 import { areValidationErrors } from '../utils'
-import { checkUserCanManageVideo, doesVideoExist } from '../../../helpers/custom-validators/videos'
 import { isIdOrUUIDValid } from '../../../helpers/custom-validators/misc'
 import { body, param } from 'express-validator/check'
 import { CONSTRAINTS_FIELDS } from '../../../initializers/constants'
 import { UserRight } from '../../../../shared'
 import { logger } from '../../../helpers/logger'
-import { doesVideoCaptionExist, isVideoCaptionFile, isVideoCaptionLanguageValid } from '../../../helpers/custom-validators/video-captions'
+import { isVideoCaptionFile, isVideoCaptionLanguageValid } from '../../../helpers/custom-validators/video-captions'
 import { cleanUpReqFiles } from '../../../helpers/express-utils'
+import { checkUserCanManageVideo, doesVideoCaptionExist, doesVideoExist } from '../../../helpers/middlewares'
 
 const addVideoCaptionValidator = [
   param('videoId').custom(isIdOrUUIDValid).not().isEmpty().withMessage('Should have a valid video id'),
diff --git a/server/middlewares/validators/videos/video-channels.ts b/server/middlewares/validators/videos/video-channels.ts
index f5a59cacb..c1065b898 100644
--- a/server/middlewares/validators/videos/video-channels.ts
+++ b/server/middlewares/validators/videos/video-channels.ts
@@ -2,8 +2,6 @@ import * as express from 'express'
 import { body, param } from 'express-validator/check'
 import { UserRight } from '../../../../shared'
 import {
-  doesLocalVideoChannelNameExist,
-  doesVideoChannelNameWithHostExist,
   isVideoChannelDescriptionValid,
   isVideoChannelNameValid,
   isVideoChannelSupportValid
@@ -15,6 +13,7 @@ import { areValidationErrors } from '../utils'
 import { isActorPreferredUsernameValid } from '../../../helpers/custom-validators/activitypub/actor'
 import { ActorModel } from '../../../models/activitypub/actor'
 import { isBooleanValid } from '../../../helpers/custom-validators/misc'
+import { doesLocalVideoChannelNameExist, doesVideoChannelNameWithHostExist } from '../../../helpers/middlewares'
 
 const videoChannelsAddValidator = [
   body('name').custom(isActorPreferredUsernameValid).withMessage('Should have a valid channel name'),
diff --git a/server/middlewares/validators/videos/video-comments.ts b/server/middlewares/validators/videos/video-comments.ts
index 6b8e2f318..1e3e42833 100644
--- a/server/middlewares/validators/videos/video-comments.ts
+++ b/server/middlewares/validators/videos/video-comments.ts
@@ -3,7 +3,6 @@ import { body, param } from 'express-validator/check'
 import { UserRight } from '../../../../shared'
 import { isIdOrUUIDValid, isIdValid } from '../../../helpers/custom-validators/misc'
 import { isValidVideoCommentText } from '../../../helpers/custom-validators/video-comments'
-import { doesVideoExist } from '../../../helpers/custom-validators/videos'
 import { logger } from '../../../helpers/logger'
 import { UserModel } from '../../../models/account/user'
 import { VideoModel } from '../../../models/video/video'
@@ -11,6 +10,7 @@ import { VideoCommentModel } from '../../../models/video/video-comment'
 import { areValidationErrors } from '../utils'
 import { Hooks } from '../../../lib/plugins/hooks'
 import { isLocalVideoThreadAccepted, isLocalVideoCommentReplyAccepted, AcceptResult } from '../../../lib/moderation'
+import { doesVideoExist } from '../../../helpers/middlewares'
 
 const listVideoCommentThreadsValidator = [
   param('videoId').custom(isIdOrUUIDValid).not().isEmpty().withMessage('Should have a valid videoId'),
diff --git a/server/middlewares/validators/videos/video-imports.ts b/server/middlewares/validators/videos/video-imports.ts
index 452084a7c..8b0dd8960 100644
--- a/server/middlewares/validators/videos/video-imports.ts
+++ b/server/middlewares/validators/videos/video-imports.ts
@@ -6,9 +6,10 @@ import { areValidationErrors } from '../utils'
 import { getCommonVideoEditAttributes } from './videos'
 import { isVideoImportTargetUrlValid, isVideoImportTorrentFile } from '../../../helpers/custom-validators/video-imports'
 import { cleanUpReqFiles } from '../../../helpers/express-utils'
-import { doesVideoChannelOfAccountExist, isVideoMagnetUriValid, isVideoNameValid } from '../../../helpers/custom-validators/videos'
+import { isVideoMagnetUriValid, isVideoNameValid } from '../../../helpers/custom-validators/videos'
 import { CONFIG } from '../../../initializers/config'
 import { CONSTRAINTS_FIELDS } from '../../../initializers/constants'
+import { doesVideoChannelOfAccountExist } from '../../../helpers/middlewares'
 
 const videoImportAddValidator = getCommonVideoEditAttributes().concat([
   body('channelId')
diff --git a/server/middlewares/validators/videos/video-playlists.ts b/server/middlewares/validators/videos/video-playlists.ts
index 9c88dd291..638122a2e 100644
--- a/server/middlewares/validators/videos/video-playlists.ts
+++ b/server/middlewares/validators/videos/video-playlists.ts
@@ -4,11 +4,10 @@ import { UserRight, VideoPlaylistCreate, VideoPlaylistUpdate } from '../../../..
 import { logger } from '../../../helpers/logger'
 import { UserModel } from '../../../models/account/user'
 import { areValidationErrors } from '../utils'
-import { doesVideoExist, isVideoImage } from '../../../helpers/custom-validators/videos'
+import { isVideoImage } from '../../../helpers/custom-validators/videos'
 import { CONSTRAINTS_FIELDS } from '../../../initializers/constants'
 import { isArrayOf, isIdOrUUIDValid, isIdValid, isUUIDValid, toIntArray, toValueOrNull } from '../../../helpers/custom-validators/misc'
 import {
-  doesVideoPlaylistExist,
   isVideoPlaylistDescriptionValid,
   isVideoPlaylistNameValid,
   isVideoPlaylistPrivacyValid,
@@ -17,11 +16,11 @@ import {
 } from '../../../helpers/custom-validators/video-playlists'
 import { VideoPlaylistModel } from '../../../models/video/video-playlist'
 import { cleanUpReqFiles } from '../../../helpers/express-utils'
-import { doesVideoChannelIdExist } from '../../../helpers/custom-validators/video-channels'
 import { VideoPlaylistElementModel } from '../../../models/video/video-playlist-element'
 import { authenticatePromiseIfNeeded } from '../../oauth'
 import { VideoPlaylistPrivacy } from '../../../../shared/models/videos/playlist/video-playlist-privacy.model'
 import { VideoPlaylistType } from '../../../../shared/models/videos/playlist/video-playlist-type.model'
+import { doesVideoChannelIdExist, doesVideoExist, doesVideoPlaylistExist } from '../../../helpers/middlewares'
 
 const videoPlaylistsAddValidator = getCommonPlaylistEditAttributes().concat([
   body('displayName')
diff --git a/server/middlewares/validators/videos/video-rates.ts b/server/middlewares/validators/videos/video-rates.ts
index 204b4a78d..5bb3f4a51 100644
--- a/server/middlewares/validators/videos/video-rates.ts
+++ b/server/middlewares/validators/videos/video-rates.ts
@@ -3,12 +3,13 @@ import 'express-validator'
 import { body, param, query } from 'express-validator/check'
 import { isIdOrUUIDValid } from '../../../helpers/custom-validators/misc'
 import { isRatingValid } from '../../../helpers/custom-validators/video-rates'
-import { doesVideoExist, isVideoRatingTypeValid } from '../../../helpers/custom-validators/videos'
+import { isVideoRatingTypeValid } from '../../../helpers/custom-validators/videos'
 import { logger } from '../../../helpers/logger'
 import { areValidationErrors } from '../utils'
 import { AccountVideoRateModel } from '../../../models/account/account-video-rate'
 import { VideoRateType } from '../../../../shared/models/videos'
 import { isAccountNameValid } from '../../../helpers/custom-validators/accounts'
+import { doesVideoExist } from '../../../helpers/middlewares'
 
 const videoUpdateRateValidator = [
   param('id').custom(isIdOrUUIDValid).not().isEmpty().withMessage('Should have a valid id'),
diff --git a/server/middlewares/validators/videos/video-shares.ts b/server/middlewares/validators/videos/video-shares.ts
index d5cbdb03e..6f4a1f3e0 100644
--- a/server/middlewares/validators/videos/video-shares.ts
+++ b/server/middlewares/validators/videos/video-shares.ts
@@ -2,10 +2,10 @@ import * as express from 'express'
 import 'express-validator'
 import { param } from 'express-validator/check'
 import { isIdOrUUIDValid, isIdValid } from '../../../helpers/custom-validators/misc'
-import { doesVideoExist } from '../../../helpers/custom-validators/videos'
 import { logger } from '../../../helpers/logger'
 import { VideoShareModel } from '../../../models/video/video-share'
 import { areValidationErrors } from '../utils'
+import { doesVideoExist } from '../../../helpers/middlewares'
 
 const videosShareValidator = [
   param('id').custom(isIdOrUUIDValid).not().isEmpty().withMessage('Should have a valid id'),
diff --git a/server/middlewares/validators/videos/video-watch.ts b/server/middlewares/validators/videos/video-watch.ts
index a3a800d14..a0b530c75 100644
--- a/server/middlewares/validators/videos/video-watch.ts
+++ b/server/middlewares/validators/videos/video-watch.ts
@@ -1,9 +1,9 @@
 import { body, param } from 'express-validator/check'
 import * as express from 'express'
 import { isIdOrUUIDValid } from '../../../helpers/custom-validators/misc'
-import { doesVideoExist } from '../../../helpers/custom-validators/videos'
 import { areValidationErrors } from '../utils'
 import { logger } from '../../../helpers/logger'
+import { doesVideoExist } from '../../../helpers/middlewares'
 
 const videoWatchingValidator = [
   param('videoId').custom(isIdOrUUIDValid).not().isEmpty().withMessage('Should have a valid id'),
diff --git a/server/middlewares/validators/videos/videos.ts b/server/middlewares/validators/videos/videos.ts
index 5593ede64..8f5e5c95c 100644
--- a/server/middlewares/validators/videos/videos.ts
+++ b/server/middlewares/validators/videos/videos.ts
@@ -13,9 +13,6 @@ import {
   toValueOrNull
 } from '../../../helpers/custom-validators/misc'
 import {
-  checkUserCanManageVideo,
-  doesVideoChannelOfAccountExist,
-  doesVideoExist,
   isScheduleVideoUpdatePrivacyValid,
   isVideoCategoryValid,
   isVideoDescriptionValid,
@@ -33,7 +30,7 @@ import {
 import { getDurationFromVideoFile } from '../../../helpers/ffmpeg-utils'
 import { logger } from '../../../helpers/logger'
 import { CONSTRAINTS_FIELDS } from '../../../initializers/constants'
-import { authenticate, authenticatePromiseIfNeeded } from '../../oauth'
+import { authenticatePromiseIfNeeded } from '../../oauth'
 import { areValidationErrors } from '../utils'
 import { cleanUpReqFiles } from '../../../helpers/express-utils'
 import { VideoModel } from '../../../models/video/video'
@@ -46,6 +43,7 @@ import { getServerActor } from '../../../helpers/utils'
 import { CONFIG } from '../../../initializers/config'
 import { isLocalVideoAccepted } from '../../../lib/moderation'
 import { Hooks } from '../../../lib/plugins/hooks'
+import { checkUserCanManageVideo, doesVideoChannelOfAccountExist, doesVideoExist } from '../../../helpers/middlewares'
 
 const videosAddValidator = getCommonVideoEditAttributes().concat([
   body('videofile')