Example for a Emscripten project boilerplate

## build.sh
#!/bin/bash

set -e

export OPTIMIZE="-Os"
export LDFLAGS="${OPTIMIZE}"
export CFLAGS="${OPTIMIZE}"
export CPPFLAGS="${OPTIMIZE}"

eval $@

echo "============================================="
echo "Compiling libvpx"
echo "============================================="
test -n "$SKIP_LIBVPX" || (
  rm -rf build-vpx || true
  mkdir build-vpx
  cd build-vpx
  emconfigure ../node_modules/libvpx/configure \
    --target=generic-gnu
  emmake make
)
echo "============================================="
echo "Compiling libvpx done"
echo "============================================="

echo "============================================="
echo "Compiling wasm bindings"
echo "============================================="
(
  # Compile C/C++ code
  emcc \
    ${OPTIMIZE} \
    --bind \
    -s STRICT=1 \
    -s ALLOW_MEMORY_GROWTH=1 \
    -s ASSERTIONS=0 \
    -s MALLOC=emmalloc \
    -s MODULARIZE=1 \
    -s EXPORT_ES6=1 \
    -o ./my-module.js \
    -I ./node_modules/libvpx \
    my-module.cpp \
    build-vpx/libvpx.a

  # Create output folder
  mkdir -p dist
  # Move artifacts
  mv my-module.{js,wasm} dist
)
echo "============================================="
echo "Compiling wasm bindings done"
echo "============================================="

## Dockerfile
FROM trzeci/emscripten

RUN apt-get update && \
    apt-get install -qqy doxygen

## index.html
<!doctype html>
Open the console to see the output from the wasm module.
<script type="module">
import wasmModule from "./my-module.js";

const instance = wasmModule({
  onRuntimeInitialized() {
    instance.sayHello();
  }
});
</script>

## my-module.cpp
#include "vpxenc.h"
#include <emscripten/bind.h>

using namespace emscripten;

int say_hello() {
  printf("Hello from your wasm module with libvpx %d\n", VPX_CODEC_ABI_VERSION);
  return 0;
}

EMSCRIPTEN_BINDINGS(my_module) {
  function("sayHello", &say_hello);
}

## package.json
{
  "name": "my-worldchanging-project",
  "scripts": {
    "install": "napa",
    "build:dockerimage": "docker image inspect -f '.' mydockerimage || docker build -t mydockerimage .",
    "build:emscripten": "docker run --rm -v $(pwd):/src mydockerimage ./build.sh",
    "build:app": "cp index.html dist/index.html",
    "build": "npm run build:dockerimage && npm run build:emscripten && npm run build:app",
    "serve": "http-server -c0 dist"
  },
  "devDependencies": {
    "http-server": "*"
  },
  "dependencies": {
    "napa": "^3.0.0"
  },
  "napa": {
    "libvpx": "git+https://github.com/webmproject/libvpx"
  }
}