straw/rust

rust/ — strawcore: Rust YouTube core for Straw

Phase U- of the Straw build. Goal: replace the Java NewPipeExtractor dependency with a Rust core (rustypipe + tokio + reqwest), exposed to the Kotlin/Compose UI via UniFFI. Compose UI stays in Kotlin — only the YouTube/Innertube fetching layer moves to Rust.

Phases

Phase	What
U-1	Toolchain + UniFFI smoke test (hello_from_rust) round-tripping through JNA. No real APIs yet.
U-2	rustypipe search. SearchViewModel calls the Rust core.
U-3	rustypipe streamInfo + streams. VideoDetailViewModel + PlayerViewModel use it.
U-4	rustypipe channel + tabs. ChannelViewModel + SubscriptionFeedViewModel.
U-5	Rip NewPipeExtractor Java dep. Measure APK + cold-fetch latency before/after.
U-6 (stretch)	SponsorBlock + RYD HTTP through reqwest + tokio in the same lib.

Build chain

Build container (Sulkta uses one; any toolchain matching this layout works)
├── rustup stable (target add: aarch64-linux-android, armv7-linux-androideabi,
│                  x86_64-linux-android, i686-linux-android)
├── cargo-ndk      (cross-compile helper)
├── android-sdk    (ANDROID_HOME, sdkmanager, build-tools, platforms)
└── android-ndk    (ANDROID_NDK_HOME, r27c LTS)

Gradle (strawApp/build.gradle.kts)
├── cargoBuild         Exec task → cargo ndk -t <abi>... -o jniLibs/ build --release
├── uniffiBindgen      Exec task → cargo run --bin uniffi-bindgen ... --library libstrawcore.so
└── source-set wiring  generated Kotlin lands in strawApp/src/main/java/uniffi/strawcore/

Runtime (StrawApp.onCreate)
├── System.loadLibrary("strawcore")
└── uniffi.strawcore.initLogging()

Why UniFFI (and not raw JNI / JNA bindings)

• Hand-written JNI: tedious, error-prone, every type change is two files (Kotlin + Rust) that must stay in sync.
• Raw JNA: better, but you still hand-write the Kotlin side and worry about string ownership.
• UniFFI: write Rust, annotate with #[uniffi::export], get a Kotlin shim generated. Strings, structs, enums, Result types, async functions all cross the boundary transparently. The runtime is JNA under the hood.

When in doubt

• cargo check -p strawcore --target aarch64-linux-android — fast iteration.
• cargo run --bin uniffi-bindgen -- generate ... — regenerate Kotlin bindings.
• adb logcat -s strawcore — Rust log::info!() lands here.
• aapt dump badging strawApp/build/outputs/apk/debug/strawApp-debug.apk — inspect what ABIs/native-libs the APK carries.