llama2c-worker.js

import { WASI } from "/vendor/wasi.js";
var context;
var result;

// Initialize WASM memory.
var wasmMemory = new WebAssembly.Memory({initial:32, maximum: 10000});
var fileRequest = await fetch(self.location.origin + '/' + 'llama2.c/tokenizer.bin');
var fileContent = await fileRequest.arrayBuffer();

var modelURL = 'https://huggingface.co/karpathy/tinyllamas/resolve/main/stories15M.bin';
if (isLocalhost()) { modelURL = self.location.origin + '/' + 'models/stories15M.bin'; }

var modelFileRequest = await fetch(modelURL);
var contentLength = modelFileRequest.headers.get('Content-Length');
var responseSize = 0;
let chunksAll = new Uint8Array(contentLength); // (4.1)

for await (var chunk of streamAsyncIterable(modelFileRequest.body)) {
  chunksAll.set(chunk, responseSize); // (4.2)
  responseSize += chunk.length;
  self.postMessage({
    eventType: "MODELDOWNLOADPROGRESS",
    eventData: responseSize / contentLength
  });
}

async function* streamAsyncIterable(stream) {
  const reader = stream.getReader()
  try {
    while (true) {
      const { done, value } = await reader.read()
      if (done) return
      yield value
    }
  } finally {
    reader.releaseLock()
  }
}

var output = '';
context = new WASI({
  args: ['run', 'model.bin', '-i', 'Once upon a time'],
  stdout: function (out) { 
            output += out;
            self.postMessage({
              eventType: "STDOUT",
              eventData: out
            });
          },
  stderr: function (err) {
    self.postMessage({
      eventType: "STDERR",
      eventData: err
    }); 
    console.error('stderr', err); 
  },
  stdin: () => prompt('stdin:'),
  fs: {
    '/model.bin': {
      path: modelFileRequest.name,
      timestamps: {
        change: new Date(modelFileRequest.headers.get('Last-Modified')),
        access: new Date(modelFileRequest.headers.get('Last-Modified')),
        modification: new Date(modelFileRequest.headers.get('Last-Modified')),
      },
      mode: 'binary',
      content: new Uint8Array(chunksAll),
    },
    '/tokenizer.bin': {
      path: 'tokenizer.bin',
      timestamps: {
        change: new Date(fileRequest.headers.get('Last-Modified')),
        access: new Date(fileRequest.headers.get('Last-Modified')),
        modification: new Date(fileRequest.headers.get('Last-Modified')),
      },
      mode: 'binary',
      content: new Uint8Array(fileContent),
    }
  }
});

var memory = new WebAssembly.Memory({ initial: 32, maximum: 10000 });
var wasm = await WebAssembly.instantiateStreaming(
  fetch('llama2c.wasm'),
  {
    ...context.getImportObject(),
    env: {memory: memory}
  }
);
result = context.start(wasm, {memory: memory});

function isLocalhost() {
  var url = self.location.origin;  
  return url.indexOf('127.0.0.1') !== -1 || url.indexOf('localhost') !== -1;
}

//result = await WASIJS.start(fetch('llama2c.wasm'), context);