5 files changed, 58 insertions, 14 deletions

diff --git a/server.ts b/server.ts
index 1cc29209e..a8bd25088 100644
--- a/server.ts
+++ b/server.ts
@@ -44,7 +44,7 @@ checkFFmpeg(CONFIG)
 
 checkNodeVersion()
 
-import { checkConfig, checkActivityPubUrls } from './server/initializers/checker-after-init'
+import { checkConfig, checkActivityPubUrls, checkFFmpegVersion } from './server/initializers/checker-after-init'
 
 const errorMessage = checkConfig()
 if (errorMessage !== null) {
@@ -252,6 +252,9 @@ async function startApplication () {
       process.exit(-1)
     })
 
+  checkFFmpegVersion()
+    .catch(err => logger.error('Cannot check ffmpeg version', { err }))
+
   // Email initialization
   Emailer.Instance.init()
 
diff --git a/server/helpers/core-utils.ts b/server/helpers/core-utils.ts
index 7ba7d865a..ceb6a341d 100644
--- a/server/helpers/core-utils.ts
+++ b/server/helpers/core-utils.ts
@@ -251,6 +251,16 @@ function promisify2<T, U, A> (func: (arg1: T, arg2: U, cb: (err: any, result: A)
   }
 }
 
+function parseSemVersion (s: string) {
+  const parsed = s.match(/^v?(\d+)\.(\d+)\.(\d+)$/i)
+
+  return {
+    major: parseInt(parsed[1]),
+    minor: parseInt(parsed[2]),
+    patch: parseInt(parsed[3])
+  }
+}
+
 const randomBytesPromise = promisify1<number, Buffer>(randomBytes)
 const createPrivateKey = promisify1<number, { key: string }>(pem.createPrivateKey)
 const getPublicKey = promisify1<string, { publicKey: string }>(pem.getPublicKey)
@@ -288,5 +298,7 @@ export {
   getPublicKey,
   execPromise2,
   execPromise,
-  pipelinePromise
+  pipelinePromise,
+
+  parseSemVersion
 }
diff --git a/server/helpers/ffmpeg-utils.ts b/server/helpers/ffmpeg-utils.ts
index 620025966..69cd397b9 100644
--- a/server/helpers/ffmpeg-utils.ts
+++ b/server/helpers/ffmpeg-utils.ts
@@ -5,7 +5,7 @@ import { dirname, join } from 'path'
 import { FFMPEG_NICE, VIDEO_LIVE } from '@server/initializers/constants'
 import { AvailableEncoders, EncoderOptionsBuilder, EncoderProfile, VideoResolution } from '../../shared/models/videos'
 import { CONFIG } from '../initializers/config'
-import { promisify0 } from './core-utils'
+import { execPromise, promisify0 } from './core-utils'
 import { computeFPS, getAudioStream, getVideoFileFPS } from './ffprobe-utils'
 import { processImage } from './image-utils'
 import { logger } from './logger'
@@ -649,6 +649,24 @@ function getFFmpeg (input: string, type: 'live' | 'vod') {
   return command
 }
 
+function getFFmpegVersion () {
+  return new Promise<string>((res, rej) => {
+    (ffmpeg() as any)._getFfmpegPath((err, ffmpegPath) => {
+      if (err) return rej(err)
+      if (!ffmpegPath) return rej(new Error('Could not find ffmpeg path'))
+
+      return execPromise(`${ffmpegPath} -version`)
+        .then(stdout => {
+          const parsed = stdout.match(/ffmpeg version .(\d+\.\d+\.\d+)/)
+          if (!parsed || !parsed[1]) return rej(new Error(`Could not find ffmpeg version in ${stdout}`))
+
+          return res(parsed[1])
+        })
+        .catch(err => rej(err))
+    })
+  })
+}
+
 async function runCommand (options: {
   command: ffmpeg.FfmpegCommand
   silent?: boolean // false
@@ -695,6 +713,7 @@ export {
   TranscodeOptionsType,
   transcode,
   runCommand,
+  getFFmpegVersion,
 
   resetSupportedEncoders,
 
diff --git a/server/initializers/checker-after-init.ts b/server/initializers/checker-after-init.ts
index 2b00e2047..a93c8b7fd 100644
--- a/server/initializers/checker-after-init.ts
+++ b/server/initializers/checker-after-init.ts
@@ -1,16 +1,17 @@
 import * as config from 'config'
-import { isProdInstance, isTestInstance } from '../helpers/core-utils'
-import { UserModel } from '../models/account/user'
-import { getServerActor, ApplicationModel } from '../models/application/application'
-import { OAuthClientModel } from '../models/oauth/oauth-client'
+import { uniq } from 'lodash'
 import { URL } from 'url'
-import { CONFIG, isEmailEnabled } from './config'
-import { logger } from '../helpers/logger'
+import { getFFmpegVersion } from '@server/helpers/ffmpeg-utils'
+import { VideoRedundancyConfigFilter } from '@shared/models/redundancy/video-redundancy-config-filter.type'
 import { RecentlyAddedStrategy } from '../../shared/models/redundancy'
+import { isProdInstance, isTestInstance, parseSemVersion } from '../helpers/core-utils'
 import { isArray } from '../helpers/custom-validators/misc'
-import { uniq } from 'lodash'
+import { logger } from '../helpers/logger'
+import { UserModel } from '../models/account/user'
+import { ApplicationModel, getServerActor } from '../models/application/application'
+import { OAuthClientModel } from '../models/oauth/oauth-client'
+import { CONFIG, isEmailEnabled } from './config'
 import { WEBSERVER } from './constants'
-import { VideoRedundancyConfigFilter } from '@shared/models/redundancy/video-redundancy-config-filter.type'
 
 async function checkActivityPubUrls () {
   const actor = await getServerActor()
@@ -176,11 +177,21 @@ async function applicationExist () {
   return totalApplication !== 0
 }
 
+async function checkFFmpegVersion () {
+  const version = await getFFmpegVersion()
+  const { major, minor } = parseSemVersion(version)
+
+  if (major < 4 || (major === 4 && minor < 1)) {
+    logger.warn('Your ffmpeg version (%s) is outdated. PeerTube supports ffmpeg >= 4.1. Please upgrade.', version)
+  }
+}
+
 // ---------------------------------------------------------------------------
 
 export {
   checkConfig,
   clientsExist,
+  checkFFmpegVersion,
   usersExist,
   applicationExist,
   checkActivityPubUrls
diff --git a/server/initializers/checker-before-init.ts b/server/initializers/checker-before-init.ts
index 565e0d1fa..65a019ca6 100644
--- a/server/initializers/checker-before-init.ts
+++ b/server/initializers/checker-before-init.ts
@@ -1,5 +1,5 @@
 import * as config from 'config'
-import { promisify0 } from '../helpers/core-utils'
+import { parseSemVersion, promisify0 } from '../helpers/core-utils'
 import { logger } from '../helpers/logger'
 
 // ONLY USE CORE MODULES IN THIS FILE!
@@ -102,8 +102,7 @@ async function checkFFmpeg (CONFIG: { TRANSCODING: { ENABLED: boolean } }) {
 
 function checkNodeVersion () {
   const v = process.version
-  const majorString = v.split('.')[0].replace('v', '')
-  const major = parseInt(majorString, 10)
+  const { major } = parseSemVersion(v)
 
   logger.debug('Checking NodeJS version %s.', v)