Migrate server to ESM

Sorry for the very big commit that may lead to git log issues and merge
conflicts, but it's a major step forward:

 * Server can be faster at startup because imports() are async and we can
   easily lazy import big modules
 * Angular doesn't seem to support ES import (with .js extension), so we
   had to correctly organize peertube into a monorepo:
    * Use yarn workspace feature
    * Use typescript reference projects for dependencies
    * Shared projects have been moved into "packages", each one is now a
      node module (with a dedicated package.json/tsconfig.json)
    * server/tools have been moved into apps/ and is now a dedicated app
      bundled and published on NPM so users don't have to build peertube
      cli tools manually
    * server/tests have been moved into packages/ so we don't compile
      them every time we want to run the server
 * Use isolatedModule option:
   * Had to move from const enum to const
     (https://www.typescriptlang.org/docs/handbook/enums.html#objects-vs-enums)
   * Had to explictely specify "type" imports when used in decorators
 * Prefer tsx (that uses esbuild under the hood) instead of ts-node to
   load typescript files (tests with mocha or scripts):
     * To reduce test complexity as esbuild doesn't support decorator
       metadata, we only test server files that do not import server
       models
     * We still build tests files into js files for a faster CI
 * Remove unmaintained peertube CLI import script
 * Removed some barrels to speed up execution (less imports)

3 files changed, 134 insertions, 0 deletions

diff --git a/packages/ffmpeg/src/shared/encoder-options.ts b/packages/ffmpeg/src/shared/encoder-options.ts
new file mode 100644
index 000000000..376a19186
--- /dev/null
+++ b/packages/ffmpeg/src/shared/encoder-options.ts
@@ -0,0 +1,39 @@
+import { FfmpegCommand } from 'fluent-ffmpeg'
+import { EncoderOptions } from '@peertube/peertube-models'
+import { buildStreamSuffix } from '../ffmpeg-utils.js'
+
+export function addDefaultEncoderGlobalParams (command: FfmpegCommand) {
+  // avoid issues when transcoding some files: https://trac.ffmpeg.org/ticket/6375
+  command.outputOption('-max_muxing_queue_size 1024')
+         // strip all metadata
+         .outputOption('-map_metadata -1')
+         // allows import of source material with incompatible pixel formats (e.g. MJPEG video)
+         .outputOption('-pix_fmt yuv420p')
+}
+
+export function addDefaultEncoderParams (options: {
+  command: FfmpegCommand
+  encoder: 'libx264' | string
+  fps: number
+
+  streamNum?: number
+}) {
+  const { command, encoder, fps, streamNum } = options
+
+  if (encoder === 'libx264') {
+    // 3.1 is the minimal resource allocation for our highest supported resolution
+    command.outputOption(buildStreamSuffix('-level:v', streamNum) + ' 3.1')
+
+    if (fps) {
+      // Keyframe interval of 2 seconds for faster seeking and resolution switching.
+      // https://streaminglearningcenter.com/blogs/whats-the-right-keyframe-interval.html
+      // https://superuser.com/a/908325
+      command.outputOption(buildStreamSuffix('-g:v', streamNum) + ' ' + (fps * 2))
+    }
+  }
+}
+
+export function applyEncoderOptions (command: FfmpegCommand, options: EncoderOptions) {
+  command.inputOptions(options.inputOptions ?? [])
+    .outputOptions(options.outputOptions ?? [])
+}
diff --git a/packages/ffmpeg/src/shared/index.ts b/packages/ffmpeg/src/shared/index.ts
new file mode 100644
index 000000000..81e8ff0b5
--- /dev/null
+++ b/packages/ffmpeg/src/shared/index.ts
@@ -0,0 +1,2 @@
+export * from './encoder-options.js'
+export * from './presets.js'
diff --git a/packages/ffmpeg/src/shared/presets.ts b/packages/ffmpeg/src/shared/presets.ts
new file mode 100644
index 000000000..17bd7b031
--- /dev/null
+++ b/packages/ffmpeg/src/shared/presets.ts
@@ -0,0 +1,93 @@
+import { pick } from '@peertube/peertube-core-utils'
+import { FFmpegCommandWrapper } from '../ffmpeg-command-wrapper.js'
+import { getScaleFilter, StreamType } from '../ffmpeg-utils.js'
+import { ffprobePromise, getVideoStreamBitrate, getVideoStreamDimensionsInfo, hasAudioStream } from '../ffprobe.js'
+import { addDefaultEncoderGlobalParams, addDefaultEncoderParams, applyEncoderOptions } from './encoder-options.js'
+
+export async function presetVOD (options: {
+  commandWrapper: FFmpegCommandWrapper
+
+  input: string
+
+  canCopyAudio: boolean
+  canCopyVideo: boolean
+
+  resolution: number
+  fps: number
+
+  scaleFilterValue?: string
+}) {
+  const { commandWrapper, input, resolution, fps, scaleFilterValue } = options
+  const command = commandWrapper.getCommand()
+
+  command.format('mp4')
+    .outputOption('-movflags faststart')
+
+  addDefaultEncoderGlobalParams(command)
+
+  const probe = await ffprobePromise(input)
+
+  // Audio encoder
+  const bitrate = await getVideoStreamBitrate(input, probe)
+  const videoStreamDimensions = await getVideoStreamDimensionsInfo(input, probe)
+
+  let streamsToProcess: StreamType[] = [ 'audio', 'video' ]
+
+  if (!await hasAudioStream(input, probe)) {
+    command.noAudio()
+    streamsToProcess = [ 'video' ]
+  }
+
+  for (const streamType of streamsToProcess) {
+    const builderResult = await commandWrapper.getEncoderBuilderResult({
+      ...pick(options, [ 'canCopyAudio', 'canCopyVideo' ]),
+
+      input,
+      inputBitrate: bitrate,
+      inputRatio: videoStreamDimensions?.ratio || 0,
+
+      resolution,
+      fps,
+      streamType,
+
+      videoType: 'vod' as 'vod'
+    })
+
+    if (!builderResult) {
+      throw new Error('No available encoder found for stream ' + streamType)
+    }
+
+    commandWrapper.debugLog(
+      `Apply ffmpeg params from ${builderResult.encoder} for ${streamType} ` +
+      `stream of input ${input} using ${commandWrapper.getProfile()} profile.`,
+      { builderResult, resolution, fps }
+    )
+
+    if (streamType === 'video') {
+      command.videoCodec(builderResult.encoder)
+
+      if (scaleFilterValue) {
+        command.outputOption(`-vf ${getScaleFilter(builderResult.result)}=${scaleFilterValue}`)
+      }
+    } else if (streamType === 'audio') {
+      command.audioCodec(builderResult.encoder)
+    }
+
+    applyEncoderOptions(command, builderResult.result)
+    addDefaultEncoderParams({ command, encoder: builderResult.encoder, fps })
+  }
+}
+
+export function presetCopy (commandWrapper: FFmpegCommandWrapper) {
+  commandWrapper.getCommand()
+    .format('mp4')
+    .videoCodec('copy')
+    .audioCodec('copy')
+}
+
+export function presetOnlyAudio (commandWrapper: FFmpegCommandWrapper) {
+  commandWrapper.getCommand()
+    .format('mp4')
+    .audioCodec('copy')
+    .noVideo()
+}