Unit tests for the project

[mpmartins]

Hey @yuval-k, Happy easter.

The more I touch this project, the more I get excited about the possibilities... :D

I wanted to open a discussion with you about the project unit tests/integration tests.

First, just wanted to say that we need to find a way to create some unit tests for the project. I couldn't find the time to study that in detail, but maybe we can use a library like https://github.com/jtenner/as-pect.

But, what I really wanted to share is that I converted your example of integration tests implemented in an HTML file to a javascript file that can be triggered using node. Take a look at my example below:

const assert = require("assert");
const fs = require("fs");
const loader = require("@assemblyscript/loader");
const util = require('util');
const utf8Decoder = new util.TextDecoder('utf-8');

/**
 * This function is used to inject values into Web Assembly VM memory.
 * 
 * @param {String} value - value to be injected into WebAssembly memory
 * @param {Number} value_ptr_ptr - pointer to the memory address that starts this variable
 * @param {Number} value_size_ptr - pointer to the memory address with variable size
 */
function injectStringIntoMemory(value, value_ptr_ptr, value_size_ptr) { 
  
  const value_size = value.length;
  let bytes = globalExports.malloc(value_size);
  if (bytes === 0) {
      throw "can't allocate";
  }

  var moduleMemory = globalExports.memory.buffer;

  var confMem = new Uint8Array(moduleMemory, bytes, value_size);
  for(let i = 0; i < value_size; i++){
      confMem[i]=value.charCodeAt(i);
  }

  var confPtr = new Uint32Array(moduleMemory, value_ptr_ptr, 1);
  confPtr[0] = bytes;
  var confSizePtr = new Uint32Array(moduleMemory, value_size_ptr, 1);
  confSizePtr[0] = value_size;

  console.info("injectStringIntoMemory: " + value + " to " + value_ptr_ptr + ":" + value_size_ptr);
}

//Mocks and hardcoded values
const root_id_string = "expo_filter_root_id"
const config = "expo_filter_configuration_value1";

const imports = {
  wasi_unstable: {
    proc_exit: console.trace
  },
  env: {
    memory: new WebAssembly.Memory({
      initial: 1,
      maximum: 1
    }),
    abort: console.trace,
    proxy_log(level, logMessage, messageSize) {
      var mem = new Uint8Array(globalExports.memory.buffer);
      let buf = mem.slice(logMessage, logMessage + messageSize);
      let msg = "proxy_log: " + utf8Decoder.decode(buf);
      switch(level) { 
        case 1: { 
          console.debug(msg); 
          break; 
        } 
        case 2: { 
          console.info(msg);
          break; 
        } 
        case 3: { 
          console.warn(msg);
          break; 
        } 
        case 4: { 
          console.error(msg);
          break; 
        } 
        default: { 
          console.trace(msg); 
          break; 
        } 
      }
      return 0;
    },
    proxy_get_configuration(configuration_ptr, configuration_size) {
      console.debug("proxy_get_configuration: " + config + ":" + configuration_ptr + ":" + configuration_size);
      injectStringIntoMemory(config, configuration_ptr, configuration_size);
      return config;
    },
    proxy_get_property(path_ptr, path_size, value_ptr_ptr, value_size_ptr) { 
      // we only support one property now, the root id.
      const prop = root_id_string;
      console.debug("proxy_get_property: " + prop + ":" + path_ptr + "-" + path_size + ":" + value_ptr_ptr + "-" + value_size_ptr);
      injectStringIntoMemory(prop, value_ptr_ptr, value_size_ptr);
      return prop;
    },
    proxy_get_status: console.trace,
    proxy_set_tick_period_milliseconds: console.trace,
    proxy_get_current_time_nanoseconds: console.trace,
    proxy_set_property: console.trace,
    proxy_continue_request: console.trace,
    proxy_continue_response: console.trace,
    proxy_send_local_response: console.trace,
    proxy_clear_route_cache: console.trace,
    proxy_get_shared_data: console.trace,
    proxy_set_shared_data: console.trace,
    proxy_register_shared_queue: console.trace,
    proxy_resolve_shared_queue: console.trace,
    proxy_dequeue_shared_queue: console.trace,
    proxy_enqueue_shared_queue: console.trace,
    proxy_add_header_map_value: console.trace,
    proxy_get_header_map_value: console.trace,
    proxy_get_header_map_pairs: console.trace,
    proxy_set_header_map_pairs: console.trace,
    proxy_replace_header_map_value: console.trace,
    proxy_remove_header_map_value: console.trace,
    proxy_get_header_map_size: console.trace,
    proxy_get_buffer_bytes: console.trace,
    proxy_get_buffer_status: console.trace,
    proxy_http_call: console.trace,
    proxy_grpc_call: console.trace,
    proxy_grpc_stream: console.trace,
    proxy_grpc_cancel: console.trace,
    proxy_grpc_close: console.trace,
    proxy_grpc_send: console.trace,
    proxy_define_metric: console.trace,
    proxy_increment_metric: console.trace,
    proxy_record_metric: console.trace,
    proxy_get_metric: console.trace,
    proxy_set_effective_context: console.trace,
    proxy_done: console.trace
  }
}

/**
 * Simple Unit test to check if the Filter can be initialized using wasm and making calls the proxy makes to initialize them.
 */
function testModuleLoading() {
  var wasm = loader.instantiateSync(fs.readFileSync(__dirname + "/../build/untouched.wasm"), imports);

  let exports = wasm;
  globalExports = exports;
  let context_id = 0;
  const root_context_id = context_id++;

  // Proxy calling Filter to initialize context
  exports.proxy_on_context_create(context_id, root_context_id);

  // Proxy calling Filter when VM is starting
  assert(exports.proxy_on_vm_start(context_id, root_context_id) === 1, "Failed to start VM.");

  // Initializing Filter
  assert(exports.proxy_on_configure(context_id++, config.length) === 1, "Failed to start filter"); 

  fs.writeFileSync("tests/memory.dump", new DataView(exports.memory.buffer, 0, exports.memory.buffer.byteLength));

  //Trying to trigger a request to the filter
  //const headers = [{"x-wmt-expo":"test"}];
  //exports.proxy_on_context_create(context_id, root_context_id);
  //let result = exports.proxy_on_request_headers(context_id, null);
  //console.log(result);
};

testModuleLoading();

This way, we can trigger the tests by just running the "node tests" command.

Thanks,
Mario

[yuval-k]

nice , thank you - this is very helpful!
i will look into the link you attached for unit testing - I was hoping AS will gain ability for interfaces soon and then i can cleanup a lot of the workarounds i had due to the lack of it, and also mock properly. I will look at the link and see how we can integrate this

[yuval-k]

i added some basic ci, that builds the example filter.
next i am hoping to integrate the integration test as outlined above; PRs welcome!

[mpmartins]

Hey, sorry for not updating this. I will try to find some time this week to create a PR to add this test to the example plugins you created.