MobDev.TfliteDownloader (mob_dev v0.5.7)

Copy Markdown View Source

Downloads and caches pre-built TensorFlow Lite native libraries for Android and iOS so Mob apps can ship the TFLite Nx backend without building TFLite from source (Bazel).

Two upstream sources:

  • Android — tensorflow-lite-2.16.1.aar from Maven Central (the last release with a packed .aar; 2.17.0 ships .jar only). Extracted to jni/arm64-v8a/libtensorflowlite_jni.so + headers/tensorflow/lite/c/c_api.h etc.
  • iOS — TensorFlowLiteC-2.17.0.tar.gz from dl.google.com (CocoaPods upstream). Contains three xcframeworks (Core, CoreML, Metal) each with ios-arm64 device + ios-arm64_x86_64-simulator slices.

The C API is binary-compatible between these versions — TFLite's c_api.h surface has been stable since 2.13. Different version pins per platform reflect upstream packaging differences, not API drift.

Mirrors the MobDev.MLXDownloader pattern: hashed URL + cached extraction at ~/.mob/cache/tflite-<version>-<target>/, validated against the expected layout. Reused across projects.

Used by MobDev.NativeBuild when the project enables TFLite via mix mob.enable tflite. The build template sources TFLITE_DIR from dir/1 and links the tflite_nif.c NIF against the headers and framework / .so it provides.

Local-build override

Set MOB_TFLITE_LOCAL_TARBALL_DIR=/path/to/dir to bypass the upstream download and use locally-fetched tarballs (named exactly as tarball_name/1 returns). Useful when iterating offline or against a custom TFLite build.

Summary

Types

target()

Target slice this downloader supports.

Functions

android_version()

Android TFLite version pin.

dir(target)

Cached TFLite root directory for target. May not exist if ensure/1 hasn't been called.

ensure(target)

Ensure the TFLite bundle for target is cached and extracted.

ios_version()

iOS TFLite version pin.

valid_dir?(target, dir)

Returns true if the cache directory has the expected layout for the given target. Public for tests and NativeBuild probing.

Types

target()

@type target() :: :android_arm64 | :android_arm32 | :ios_device | :ios_sim

Target slice this downloader supports.

Functions

android_version()

@spec android_version() :: String.t()

Android TFLite version pin.

dir(target)

@spec dir(target()) :: String.t()

Cached TFLite root directory for target. May not exist if ensure/1 hasn't been called.

ensure(target)

@spec ensure(target()) :: {:ok, String.t()} | {:error, term()}

Ensure the TFLite bundle for target is cached and extracted.

Returns {:ok, path} where path is the unpacked root containing the expected layout (see valid_dir?/2).

ios_version()

@spec ios_version() :: String.t()

iOS TFLite version pin.

valid_dir?(target, dir)

@spec valid_dir?(target(), String.t()) :: boolean()

Returns true if the cache directory has the expected layout for the given target. Public for tests and NativeBuild probing.