android: we can actually build an gomobile aar now

android/.gitignore

@@ -0,0 +1,2 @@
+*.jar
+*.aar

android/Makefile

@@ -1,3 +1,3 @@
 .PHONY: build
 build:
-	gomobile bind -target=android github.com/luk-ai/lukai/bindable
+	gomobile bind -x -v -target=android -ldflags="-extldflags=-L$(shell pwd)" github.com/luk-ai/lukai/bindable

android/readme.md

@@ -3,4 +3,53 @@
 This is the home of the android client library. It's mostly generated bindings
 via gomobile.
 
-To build you need to install android-ndk-r12b and build [Tensorflow for android](https://github.com/tensorflow/tensorflow/tree/master/tensorflow/contrib/android).
+## Dependencies
+
+* android-sdk (and related tools)
+* android-ndk-r14b
+* android-platform-23
+
+To build you need to install android and build
+[Tensorflow for android](https://github.com/tensorflow/tensorflow/tree/master/tensorflow/contrib/android).
+You'll need to use the
+[luk-ai/tensorflow fork](https://github.com/luk-ai/tensorflow)
+and then run the commands below. Other versions of the NDK may work, but are
+untested.
+
+Commands to build Android dependencies:
+
+### Arm
+```
+sed -i 's/api_level=21,/api_level=15,/g' WORKSPACE
+bazel build -c opt --verbose_failures //tensorflow/contrib/android:libtensorflow_inference.so --crosstool_top=//external:android/crosstool --host_crosstool_top=@bazel_tools//tools/cpp:toolchain --cpu=armeabi-v7a
+mkdir -p $GOPATH/pkg/gomobile/lib/arm
+cp $ANDROID_NDK_HOME/platforms/android-15/arch-arm/usr/lib/* $GOPATH/pkg/gomobile/lib/arm/
+cp -f bazel-bin/tensorflow/contrib/android/libtensorflow_inference.so $GOPATH/pkg/gomobile/lib/arm/libtensorflow.so
+```
+
+### Arm64
+```
+sed -i 's/api_level=15,/api_level=21,/g' WORKSPACE
+bazel build -c opt --verbose_failures //tensorflow/contrib/android:libtensorflow_inference.so --crosstool_top=//external:android/crosstool --host_crosstool_top=@bazel_tools//tools/cpp:toolchain --cpu=arm64-v8a
+mkdir -p $GOPATH/pkg/gomobile/lib/arm64
+cp $ANDROID_NDK_HOME/platforms/android-21/arch-arm64/usr/lib/* $GOPATH/pkg/gomobile/lib/arm64/
+cp -f bazel-bin/tensorflow/contrib/android/libtensorflow_inference.so $GOPATH/pkg/gomobile/lib/arm64/libtensorflow.so
+```
+
+### x86
+```
+sed -i 's/api_level=21,/api_level=15,/g' WORKSPACE
+bazel build -c opt --verbose_failures //tensorflow/contrib/android:libtensorflow_inference.so --crosstool_top=//external:android/crosstool --host_crosstool_top=@bazel_tools//tools/cpp:toolchain --cpu=x86
+mkdir -p $GOPATH/pkg/gomobile/lib/386
+cp $ANDROID_NDK_HOME/platforms/android-15/arch-x86/usr/lib/* $GOPATH/pkg/gomobile/lib/386/
+cp -f bazel-bin/tensorflow/contrib/android/libtensorflow_inference.so $GOPATH/pkg/gomobile/lib/386/libtensorflow.so
+```
+
+### x86_64
+```
+sed -i 's/api_level=15,/api_level=21,/g' WORKSPACE
+bazel build -c opt --verbose_failures //tensorflow/contrib/android:libtensorflow_inference.so --crosstool_top=//external:android/crosstool --host_crosstool_top=@bazel_tools//tools/cpp:toolchain --cpu=x86_64
+mkdir -p $GOPATH/pkg/gomobile/lib/amd64
+cp $ANDROID_NDK_HOME/platforms/android-21/arch-x86_64/usr/lib/* $GOPATH/pkg/gomobile/lib/amd64/
+cp -f bazel-bin/tensorflow/contrib/android/libtensorflow_inference.so $GOPATH/pkg/gomobile/lib/amd64/libtensorflow.so
+```