How to migrate to Lumen SDK 22.X (AVPlayer)

Overview

The following article will explain all breaking changes, renamed functions and configuration objects, that need to be fulfilled to migrate and benefit from all the major performance and usability improvements that become available with our new iOS/tvOS SDK 22.X

The new iOS/tvOS SDK 22.X reflect our Lumen transition as well many rework of our internal modules architecture.

We have put a lot of effort to make sure the integration remains as simple as possible and as close to what we had in the previous versions.

Most of the changes concerns renaming from "streamroot" to "lumen" and from "DNA" to "MESH".

The complete integration steps to follow for a brand new integration can be found at AVplayer from SDK 22.01.

In summary

Footprint

Compared to previous versions:

2x less average user CPU time
4x less average RAM usage, runtime is ~17MB (plus configurable P2P cache size, by default 60MB for live and 80MB for VOD)
Lower device hardware requirement compatibility (e.g. 4cores CPU, 1GB RAM)

SDK size

Total bundle 14-17MB (final size depends on the device CPU architecture)

Features

Increased CDN Offload: expect +5-20% of P2P offload
Reduced footprint on low-end devices
Improved reaction to network speed changes
Additional client side debugging tools, via Stats View external library

Versioning scheme

The SDK now uses a date-based versioning scheme.
It is based on Year, Month, Patch as follows: YY.MM.patch

Dependency

The full dependency of the SDK changed from StreamrootSDK to LumenMeshSDK.

It is now declared as follows:

Before 22.01

With Cocoapods

use_frameworks!
target ' <Your Target Name >'
  pod 'StreamrootSDK', '~> 3.25.1'
end

With Carthage

binary "https://sdk.streamroot.io/ios/StreamrootSDK.json" ~> 3.25.1
github "daltoniam/Starscream" ~> 3.1.1
github "getsentry/sentry-cocoa" ~> 4.4.0
github "apple/swift-protobuf" ~> 1.7.0

From 22.01

With Cocoapods

use_frameworks!
target '<Your Target Name> '
  pod 'LumenMeshSDK', '~> 22.01.0'
end

With Carthage

binary "https://sdk.streamroot.io/ios/LumenMeshSDK.json"

Unique customer key setting

The unique identifier that you can find in the Account section of the Lumen Dashboard has been renamed from streamroot to DeliveryClient.

It must be added in the "Info.plist" as follows:

Before 22.01

<key>Streamroot</key>
<dict>
  <key>Key</key>
  <string>streamrootKey</string>
</dict>

From 22.01

<key>DeliveryClient</key>
<dict>
  <key>Key</key>
  <string>deliveryClientKey</string>
</dict>

Importing the SDK

The SDK name has been renamed from StreamrootSDK to LumenOrchestratorSDK.

Before 22.01

It also has been implemented in Objective-C, so to import it in a swift project a bridge-header is needed (see Apple documentation)

#import <StreamrootSDK/StreamrootSDK.h>

From 22.01

Just import the SDK

#import LumenMeshSDK

SDK Initialization

The SDK has now a new step for initialization.

It must be done from the App delegate application(_:didFinishLaunchingWithOptions:) function as follow:

Before 22.01

None

From 22.01

LMDeliveryClient.initializeApp()

Lumen Delivery Client instance build, start and stop.

The way to build the Lumen Delivery Client instances has changed in many ways from DNAClient.builder() to LMDeliveryClientBuilder.clientBuilder()and the start is now done in a separate method.

It is also not needed to pass the identifier at this stage anymore.

Before 22.01

Build and start of the DC instance are done at the same time as follow:

do {
    dnaClient = try DNAClient.builder()
        .dnaClientDelegate(self)
        .latency(30)
        .streamrootKey(<#streamrootKey#>)
        .start(manifestUrl)
} catch let error {
    print("\(error)")
}

And calling the stop() method on the DC will stop the SDK.

dnaClient?.stop()

From 22.01

Build of the DC instance is done as follow:

deliveryClient = LMDeliveryClientBuilder.clientBuilder()
     .playerInteractor(<#playerInteractor#>)
     .contentId(<#string#>)
     .meshProperty(<#string#>)   
     .build(<#manifestUrl#>)

And calling the start() method on the DC will start the SDK.

deliveryClient?.start()

Then calling the stop() method on the DC will stop the SDK.

deliveryClient?.stop()

Get new local URL

The method has been renamed from dnaClient?.manifestLocalURLPath to deliveryClient?.localManifestURL.

You must retrieve the new local URL as follows:

Before 22.01

guard let localPath = self.dnaClient?.manifestLocalURLPath,
  let localUrl = URL(string: localPath) else  {
  print("Could not generate localPath, please check your network")
  return
  }

From 22.01

guard let deliveryUrl = deliveryClient?.localManifestURL else {
  print("Local Url manifets could not be generated")
  return
}

Integrate the Player interactor

A lots of changes have been made across the player interactor to always ensure best QOS and efficiency.

It now

Before 22.01

See DNAClientDelegate

See QoSModule

From 22.01

import AVKit
import LumenMeshSDK

class PlayerInteractor: LMPlayerInteractorBase {
  fileprivate var player: AVPlayer?
  fileprivate var playbackState: LMPlaybackState
  fileprivate var observer: Any?

  override init() {
    self.playbackState = .idle
    super.init()
  }

  func linkPlayer(_ player: AVPlayer) {
    self.player = player
    guard let playerItem = player.currentItem else { return }

    NotificationCenter.default.addObserver(self, selector: #selector(handlePlayedToEndFail),
                                           name: NSNotification.Name.AVPlayerItemFailedToPlayToEndTime,
                                           object: playerItem)
    NotificationCenter.default.addObserver(self, selector: #selector(handlePlayToEndSucceded),
                                           name: NSNotification.Name.AVPlayerItemDidPlayToEndTime,
                                           object: playerItem)
    NotificationCenter.default.addObserver(self, selector: #selector(handleAccesLogEntry),
                                           name: NSNotification.Name.AVPlayerItemNewAccessLogEntry,
                                           object: playerItem)
    NotificationCenter.default.addObserver(self, selector: #selector(handleErrorLogEntry),
                                           name: NSNotification.Name.AVPlayerItemNewErrorLogEntry,
                                           object: playerItem)
    NotificationCenter.default.addObserver(self, selector: #selector(handleItemPlayBackJumped),
                                           name: AVPlayerItem.timeJumpedNotification,
                                           object: playerItem)
    NotificationCenter.default.addObserver(self, selector: #selector(handleItemPlayBackStall),
                                           name: NSNotification.Name.AVPlayerItemPlaybackStalled,
                                           object: playerItem)
    player.addObserver(self, forKeyPath: "rate", options: NSKeyValueObservingOptions.new, context: nil)
    observePlayback()
  }

  func unlink() {
    if let observer = self.observer {
      player?.removeTimeObserver(observer)
      self.observer = nil
    }

    NotificationCenter.default.removeObserver(self, name: NSNotification.Name.AVPlayerItemFailedToPlayToEndTime,
                                              object: player?.currentItem)
    NotificationCenter.default.removeObserver(self, name: NSNotification.Name.AVPlayerItemDidPlayToEndTime,
                                              object: player?.currentItem)
    NotificationCenter.default.removeObserver(self, name: NSNotification.Name.AVPlayerItemNewAccessLogEntry,
                                              object: player?.currentItem)
    NotificationCenter.default.removeObserver(self, name: NSNotification.Name.AVPlayerItemNewErrorLogEntry,
                                              object: player?.currentItem)
    NotificationCenter.default.removeObserver(self, name: AVPlayerItem.timeJumpedNotification,
                                              object: player?.currentItem)
    NotificationCenter.default.removeObserver(self, name: NSNotification.Name.AVPlayerItemPlaybackStalled,
                                              object: player?.currentItem)
    player?.removeObserver(self, forKeyPath: "rate")
  }

  deinit {
    unlink()
  }

  fileprivate func updateState(_ state: LMPlaybackState) {
    if playbackState != state {
      super.playerStateDidChange(state)
      playbackState = state
    }
  }

  public override func observeValue(forKeyPath keyPath: String?,
                                    of _: Any?,
                                    change _: [NSKeyValueChangeKey: Any]?,
                                    context _: UnsafeMutableRawPointer?) {
    if keyPath == "rate", player?.rate == 0.0 {
      updateState(.paused)
    }
  }

  fileprivate func observePlayback() {
    if let observer = self.observer {
      player?.removeTimeObserver(observer)
      self.observer = nil
    }

    // Invoke callback every half second
    let interval = CMTime(seconds: 1,
                          preferredTimescale: CMTimeScale(NSEC_PER_SEC))
    // Queue on which to invoke the callback
    let mainQueue = DispatchQueue.main
    // Add time observer
    observer = player?.addPeriodicTimeObserver(forInterval: interval, queue: mainQueue) { [weak self] _ in
      guard let self = self else { return }

      let playbackLikelyToKeepUp: Bool = self.player?.currentItem?.isPlaybackLikelyToKeepUp ?? false
      if !playbackLikelyToKeepUp {
        // rebuffering
        self.updateState(.buffering)
      } else {
        // playing
        let rate = self.player?.rate
        if rate == 1.0, self.player?.error == nil {
          self.updateState(.playing)
        }
      }
    }
  }
}

// MARK: - Handler
extension PlayerInteractor {
  @objc private func handlePlayedToEndFail(_: Notification) {
    super.playbackErrorOccurred()
  }

  @objc private func handlePlayToEndSucceded(_: Notification) {
    updateState(.ended)
  }

  @objc private func handleAccesLogEntry(_: Notification) {
    guard let playerEvents = player?.currentItem?.accessLog()?.events.first else {
      return
    }
    // trackswitch
    if playerEvents.switchBitrate > 0 {
      super.trackSwitchOccurred()
    }
    // dropframe
    if playerEvents.numberOfDroppedVideoFrames > 0 {
      super.updateDroppedFrameCount(playerEvents.numberOfDroppedVideoFrames)
    }
  }

  @objc private func handleErrorLogEntry(_: Notification) {
    super.playbackErrorOccurred()
  }

  @objc private func handleItemPlayBackJumped(_: Notification) {
    updateState(.seeking)
  }

  @objc private func handleItemPlayBackStall(_: Notification) {
    updateState(.buffering)
  }
}

// MARK: - PlayerInteractor
extension PlayerInteractor {
    public override func playbackTime() -> Double {
        if let player = self.player {
            return CMTimeGetSeconds(player.currentTime())
        }
        return 0.0
    }

    public override func bufferHealth() -> Double {
        if let playerItem = self.player?.currentItem {
            let time = CMTimeGetSeconds(playerItem.currentTime())
            let timeRanges = playerItem.loadedTimeRanges.filter { CMTimeGetSeconds($0.timeRangeValue.end) > time }
            return timeRanges.map {
                CMTimeGetSeconds($0.timeRangeValue.end)
            }.reduce(0) { $0 + ($1 - time) }
        }
        return 0.0
    }

    public override func bufferTarget() -> Double {
        if #available(iOS 10.0, tvOS 10.0, *) {
            return self.player?.currentItem?.preferredForwardBufferDuration ?? 0
        }
        return 0.0
    }

    public override func setBufferTarget(_ target: Double) {
        if #available(iOS 10.0, tvOS 10.0, *) {
            self.player?.currentItem?.preferredForwardBufferDuration = target
        }
    }

    public override func setEstimatedBandwidth(_ bps: NSNumber?) {
        NSLog("[Lumen] setEstimatedBandwidth called with value \(bps != nil ? "\(bps!.uint64Value)" : "null")")
        guard let bps = bps else { return }
        self.player?.currentItem?.preferredPeakBitRate = bps.doubleValue
    }
}

Debug tools (Stats View)

The Stats View has been completely redesigned and is part of a new library. More information at Debug tools for iOS/tvOS from SDK 22.01.

Before 22.01

A helper method is available to display various Mesh related stats on a specified UIView.

[self.dnaClient displayStatsOnView: self.contentOverlayView];

From 22.01

A helper method is available to display various Mesh related stats on a specified UIView.

self.deliveryClient.displayStatWiew(someView!)

How Tos

Overview

In summary

Footprint

SDK size

Features

Versioning scheme

Dependency

Before 22.01

From 22.01

Unique customer key setting

Before 22.01

From 22.01

Importing the SDK

Before 22.01

From 22.01

SDK Initialization

Before 22.01

From 22.01

Lumen Delivery Client instance build, start and stop.

Before 22.01

From 22.01

Get new local URL

Before 22.01

From 22.01

Integrate the Player interactor

Before 22.01

From 22.01

Debug tools (Stats View)

Before 22.01

From 22.01

In this article

How To​s

Overview

In summary

Footprint​

SDK size​

Features​

Versioning scheme​

Dependency

Before 22.01

From 22.01

Unique customer key setting

Before 22.01

From 22.01

Importing the SDK

Before 22.01

From 22.01

SDK Initialization

Before 22.01

From 22.01

Lumen Delivery Client instance build, start and stop.

Before 22.01

From 22.01

Get new local URL

Before 22.01

From 22.01

Integrate the Player interactor

Before 22.01

From 22.01

Debug tools (Stats View)

Before 22.01

From 22.01

Related articles

In this article

How Tos

Footprint

SDK size

Features

Versioning scheme