sabr-exoplayer

An Android library that integrates YouTube's SABR (Server-Managed Adaptive Bitrate) playback strategy with ExoPlayer. It includes manifest parsing, request/session management, protos, a default SABR data source/fetcher implementation, and a sample app that can be run directly on an emulator/device.

Modules

• :sabr-exoplayer – the reusable library module containing the SABR implementation (manifest parser, session manager, session state, SABR data source/fetcher, protobuf models, logging utilities, etc.).
• :sample – a minimal app demonstrating the library. Launch it on an emulator/device to play the included sample SABR DASH manifest via ExoPlayer.

Features

• Parses SABR DASH manifests (including SupplementalProperty SABR payloads).
• Tracks session state (SABR contexts, request metadata, playback cookies, buffered ranges).
• Provides a custom DataSource.Factory and DefaultSabrSegmentFetcher to intercept SABR stream requests and negotiate follow-up/fallback segments with the backend.
• Includes the protos (lite) required to model SABR requests/responses, compiled with protoc 3.24.4.
• Ships a sample manifest and a demo app to verify SABR playback end-to-end.

Requirements

• Android Gradle Plugin 8.1+
• Kotlin 1.9+
• minSdk 21, targetSdk 34
• JDK 17 for building (the sample app and library both assume JDK 17 and set org.gradle.java.home accordingly).

Build

./gradlew :sabr-exoplayer:assembleDebug   # Build the library
./gradlew :sample:assembleDebug           # Build the demo app

The sample APK (sample/build/outputs/apk/debug/) can be installed on an emulator/device. It plays a bundled SABR DASH manifest using the library.

Publish / Consume

For development you can include the module as a local project. For production, add publishing logic (e.g., Maven publishing) to push artifacts to Maven Central or GitHub Packages. Once published you can use the dependency from another project, for example:

dependencies {
    implementation 'com.yourorg:sabr-exoplayer:<version>'
}

Getting Started (Sample App)

1. Install the APK or run the :sample app from Android Studio.
2. The sample app loads sabr/sample_sabr_manifest.mpd and plays it via ExoPlayer using the library.

Optional: Request/Response Dumping

If you need to inspect SABR traffic, you can pass a SabrSegmentDumper when constructing the DefaultSabrSegmentFetcher. By default, no dumps occur. Example:

val dumper = SabrSegmentDumper(
    baseUrl = HttpUrl.get("http://your-dump-server/dump"),
    callFactory = okHttpClient,
    logger = logger,
)

val segmentFetcher = DefaultSabrSegmentFetcher(
    callFactory = okHttpClient,
    logger = logger,
    segmentDumper = dumper,
)

val sabrFactory = SabrDataSourceFactory(
    delegateFactory = httpFactory,
    sessionManager = sessionManager,
    sessionProvider = { session },
    segmentFetcher = segmentFetcher,
    logger = logger,
)

The dumper mirrors requests and responses to baseUrl via HTTP POST. Provide your own endpoint if important for diagnostics. Omit segmentDumper (the default) to run without dumps in production. For a concrete Python example, see docs/sabr_segment_dumper.md.

Directory Structure

sabr-exoplayer/
├── sabr-exoplayer/             # library module
│   ├── src/main/java/com/googlevideo/sabr/...
│   ├── src/main/proto/com/googlevideo/sabr/...
├── sample/                    # demo app module
│   ├── src/main/java/com/googlevideo/sabr/sample/...
│   └── src/main/assets/sabr/sample_sabr_manifest.mpd
├── build.gradle
├── gradle.properties
├── settings.gradle
└── README.md

License

This project is licensed under the MIT License.