Implement AsyncProgressWorker

Author: legendecas

doc/async_progress_worker.md

@@ -9,7 +9,9 @@
 
 // Note: Do not include this file directly! Include "napi.h" instead.
 
+#include <algorithm>
 #include <cstring>
+#include <mutex>
 #include <type_traits>
 
 namespace Napi {
@@ -4112,6 +4114,91 @@ inline void ThreadSafeFunction::CallJS(napi_env env,
     Function(env, jsCallback).Call({});
   }
 }
+
+////////////////////////////////////////////////////////////////////////////////
+// Async Progress Worker class
+////////////////////////////////////////////////////////////////////////////////
+
+template<class T>
+inline AsyncProgressWorker<T>::AsyncProgressWorker(const Function& callback,
+                                                const char* resource_name,
+                                                const Object& resource)
+                           : AsyncWorker(callback, resource_name, resource), _asyncdata(nullptr), _asyncsize(0) {
+  _tsfn = ThreadSafeFunction::New(callback.Env(), callback, resource_name, 1, 1);
+}
+
+template<class T>
+inline AsyncProgressWorker<T>::~AsyncProgressWorker() {
+  // Abort pending tsfn call.
+  // Don't send progress events after we've already completed.
+  _tsfn.Abort();
+  {
+    std::lock_guard<std::mutex> lock(_mutex);
+    _asyncdata = nullptr;
+    _asyncsize = 0;
+  }
+  _tsfn.Release();
+}
+
+template<class T>
+inline void AsyncProgressWorker<T>::Execute() {
+  ExecutionProgress progress(this);
+  Execute(progress);
+}
+
+template<class T>
+inline void AsyncProgressWorker<T>::WorkProgress_(Napi::Env /* env */, Napi::Function /* jsCallback */, void* _data) {
+  AsyncProgressWorker* self = static_cast<AsyncProgressWorker*>(_data);
+
+  T* data;
+  size_t size;
+  {
+    std::lock_guard<std::mutex> lock(self->_mutex);
+    data = self->_asyncdata;
+    size = self->_asyncsize;
+    self->_asyncdata = nullptr;
+    self->_asyncsize = 0;
+  }
+
+  self->OnProgress(data, size);
+  delete[] data;
+}
+
+template<class T>
+inline void AsyncProgressWorker<T>::SendProgress_(const T* data, size_t count) {
+    T* new_data = new T[count];
+    {
+      T* it = new_data;
+      std::copy(data, data + count, it);
+    }
+
+    T* old_data;
+    {
+      std::lock_guard<std::mutex> lock(_mutex);
+      old_data = _asyncdata;
+      _asyncdata = new_data;
+      _asyncsize = count;
+    }
+    _tsfn.NonBlockingCall(this, WorkProgress_);
+
+    delete[] old_data;
+}
+
+template<class T>
+inline void AsyncProgressWorker<T>::Signal() const {
+  _tsfn.NonBlockingCall(this, WorkProgress_);
+}
+
+template<class T>
+inline void AsyncProgressWorker<T>::ExecutionProgress::Signal() const {
+  _that->Signal();
+}
+
+template<class T>
+inline void AsyncProgressWorker<T>::ExecutionProgress::Send(const T* data, size_t count) const {
+  _that->SendProgress_(data, count);
+}
+
 #endif
 
 ////////////////////////////////////////////////////////////////////////////////

napi-inl.h

@@ -5,6 +5,7 @@
 #include <functional>
 #include <initializer_list>
 #include <memory>
+#include <mutex>
 #include <string>
 #include <vector>
 
@@ -2061,6 +2062,42 @@ namespace Napi {
     std::unique_ptr<napi_threadsafe_function, Deleter> _tsfn;
     Deleter _d;
   };
+
+  template<class T>
+  class AsyncProgressWorker : public AsyncWorker {
+    public:
+     virtual ~AsyncProgressWorker();
+
+     class ExecutionProgress {
+        friend class AsyncProgressWorker;
+       public:
+        void Signal() const;
+        void Send(const T* data, size_t count) const;
+       private:
+        explicit ExecutionProgress(AsyncProgressWorker* that) : _that(that) {}
+        AsyncProgressWorker* const _that;
+     };
+
+    protected:
+     explicit AsyncProgressWorker(const Function& callback,
+                                  const char* resource_name,
+                                  const Object& resource);
+
+     virtual void Execute(const ExecutionProgress& progress) = 0;
+     virtual void OnProgress(const T* data, size_t count) = 0;
+
+    private:
+     static void WorkProgress_(Napi::Env env, Napi::Function jsCallback, void* data);
+
+     void Execute() override;
+     void Signal() const;
+     void SendProgress_(const T* data, size_t count);
+
+     std::mutex _mutex;
+     T* _asyncdata;
+     size_t _asyncsize;
+     ThreadSafeFunction _tsfn;
+  };
   #endif
 
   // Memory management.

napi.h

@@ -0,0 +1,84 @@
+#include "napi.h"
+
+#include <chrono>
+#include <condition_variable>
+#include <mutex>
+#include <thread>
+
+#if (NAPI_VERSION > 3)
+
+using namespace Napi;
+
+namespace {
+
+struct ProgressData {
+  size_t progress;
+};
+
+class TestWorker : public AsyncProgressWorker<ProgressData> {
+public:
+  static void DoWork(const CallbackInfo& info) {
+    bool succeed = info[0].As<Boolean>();
+    Object resource = info[1].As<Object>();
+    Function cb = info[2].As<Function>();
+    Value data = info[3];
+
+    TestWorker* worker = new TestWorker(cb, "TestResource", resource);
+    worker->Receiver().Set("data", data);
+    worker->_succeed = succeed;
+    worker->Queue();
+  }
+
+protected:
+  void Execute(const ExecutionProgress& progress) override {
+    ProgressData data{0};
+    std::unique_lock<std::mutex> lock(_cvm);
+    data.progress = 0;
+    progress.Send(&data, 1);
+    _cv.wait(lock);
+
+    data.progress = 50;
+    progress.Send(&data, 1);
+    _cv.wait(lock);
+    if (!_succeed) {
+      SetError("test error");
+    }
+    data.progress = 75;
+    progress.Send(&data, 1);
+    _cv.wait(lock);
+  }
+
+  void OnProgress(const ProgressData* data, size_t /* count */) override {
+    FunctionReference& callback = Callback();
+    Napi::Env env = Env();
+    if (!callback.IsEmpty()) {
+      Value err = env.Undefined();
+      Number progress = Number::New(env, data->progress);
+      callback.Call(Receiver().Value(), { err, progress });
+    }
+    _cv.notify_one();
+  }
+
+  std::vector<napi_value> GetResult(Napi::Env env) override {
+    Value err = env.Undefined();
+    Number progress = Number::New(env, 100);
+    return {err, progress};
+  }
+
+private:
+  TestWorker(Function cb, const char* resource_name, const Object& resource)
+      : AsyncProgressWorker(cb, resource_name, resource) {}
+  std::condition_variable _cv;
+  std::mutex _cvm;
+  bool _succeed;
+};
+
+}
+
+Object InitAsyncProgressWorker(Env env) {
+  Object exports = Object::New(env);
+  exports["doWork"] = Function::New(env, TestWorker::DoWork);
+  return exports;
+}
+
+#endif

test/asyncprogressworker.cc

@@ -0,0 +1,38 @@
+'use strict';
+const buildType = process.config.target_defaults.default_configuration;
+const common = require('./common')
+const assert = require('assert');
+
+test(require(`./build/${buildType}/binding.node`));
+test(require(`./build/${buildType}/binding_noexcept.node`));
+
+function test(binding) {
+  success(binding);
+  fail(binding);
+  return;
+}
+
+function success(binding) {
+  const expected = [0, 50, 75, 100];
+  const actual = [];
+  binding.asyncprogressworker.doWork(true, {}, common.mustCall((err, _progress) => {
+    if (err) {
+      assert.fail(err);
+      return;
+    }
+    actual.push(_progress);
+    if (actual.length === expected.length) {
+      assert.deepEqual(actual, expected);
+    }
+  }, expected.length));
+}
+
+function fail(binding) {
+  let err = undefined
+  binding.asyncprogressworker.doWork(false, {}, (_err) => {
+    err = _err;
+  });
+  process.on('exit', () => {
+    assert.throws(() => { throw err }, /test error/)
+  });
+}

test/asyncprogressworker.js

@@ -5,6 +5,9 @@ using namespace Napi;
 
 Object InitArrayBuffer(Env env);
 Object InitAsyncContext(Env env);
+#if (NAPI_VERSION > 3)
+Object InitAsyncProgressWorker(Env env);
+#endif
 Object InitAsyncWorker(Env env);
 Object InitPersistentAsyncWorker(Env env);
 Object InitBasicTypesArray(Env env);
@@ -49,6 +52,9 @@ Object InitThunkingManual(Env env);
 Object Init(Env env, Object exports) {
   exports.Set("arraybuffer", InitArrayBuffer(env));
   exports.Set("asynccontext", InitAsyncContext(env));
+#if (NAPI_VERSION > 3)
+  exports.Set("asyncprogressworker", InitAsyncProgressWorker(env));
+#endif
   exports.Set("asyncworker", InitAsyncWorker(env));
   exports.Set("persistentasyncworker", InitPersistentAsyncWorker(env));
   exports.Set("basic_types_array", InitBasicTypesArray(env));

test/binding.cc

@@ -7,6 +7,7 @@
     'sources': [
         'arraybuffer.cc',
         'asynccontext.cc',
+        'asyncprogressworker.cc',
         'asyncworker.cc',
         'asyncworker-persistent.cc',
         'basic_types/array.cc',

test/binding.gyp

@@ -10,6 +10,7 @@ process.config.target_defaults.default_configuration =
 let testModules = [
   'arraybuffer',
   'asynccontext',
+  'asyncprogressworker',
   'asyncworker',
   'asyncworker-nocallback',
   'asyncworker-persistent',
@@ -66,6 +67,7 @@ if ((process.env.npm_config_NAPI_VERSION !== undefined) &&
 
 if ((process.env.npm_config_NAPI_VERSION !== undefined) &&
     (process.env.npm_config_NAPI_VERSION < 4)) {
+  testModules.splice(testModules.indexOf('asyncprogressworker'), 1);
   testModules.splice(testModules.indexOf('threadsafe_function/threadsafe_function_ptr'), 1);
   testModules.splice(testModules.indexOf('threadsafe_function/threadsafe_function'), 1);
 }