react-native code-gen > Add a C++ only TurboModule example (for Andro…

…id/iOS/macOS/Windows) (#35138)

Summary:
Pull Request resolved: #35138

Changelog:

[General][Added] - Add a C++ only TurboModule example (for Android/iOS/macOS/Windows)

react-native@0.69 introduced a new bridging layer to ease integration for pure C++ TurboModules using C++ std:: types directly instead of the lower level jsi:: types:
https://github.com/facebook/react-native/tree/v0.69.0/ReactCommon/react/bridging

This bridging layer can be used in JSI functions or more conveniently in C++ TurboModules.

Here is a example of an C++ only TurboModule which will work on Android and iOS and macOS/Windows (using microsoft/react-native-macos|windows) only using flow/TypeScript and standard C++ types.

C++ only TurboModules are very handy as they do not require to work with JSI APIs - instead std:: or custom C++ can by used.

Differential Revision: D39011736

fbshipit-source-id: ae51d375c2056b977c27a9141a681101df68e211

packages/rn-tester/BUCK

@@ -1,3 +1,4 @@
+load("@fbsource//tools/build_defs:glob_defs.bzl", "subdir_glob")
 load("@fbsource//xplat/hermes/defs:hermes.bzl", "HERMES_BYTECODE_VERSION")
 load("//tools/build_defs:fb_native_wrapper.bzl", "fb_native")
 load("//tools/build_defs:fb_xplat_platform_specific_rule.bzl", "fb_xplat_platform_specific_rule")
@@ -10,6 +11,7 @@ load("//tools/build_defs/apple:flag_defs.bzl", "get_objc_arc_preprocessor_flags"
 load("//tools/build_defs/oss:metro_defs.bzl", "rn_library")
 load(
     "//tools/build_defs/oss:rn_defs.bzl",
+    "ANDROID",
     "APPLE",
     "YOGA_APPLE_TARGET",
     "js_library_glob",
@@ -49,6 +51,7 @@ rn_library(
     srcs = js_library_glob(
         [
             "js",
+            "NativeCxxModuleExample",
             "NativeModuleExample",
             "NativeComponentExample",
             "RCTTest",
@@ -319,3 +322,40 @@ rn_xplat_cxx_library2(
         "//xplat/js/react-native-github:RCTFabricComponentViewsBase",
     ],
 )
+
+rn_xplat_cxx_library2(
+    name = "NativeCxxModuleExample",
+    srcs = glob(["NativeCxxModuleExample/*.cpp"]),
+    header_namespace = "",
+    exported_headers = subdir_glob(
+        [
+            ("NativeCxxModuleExample", "*.h"),
+        ],
+        prefix = "NativeCxxModuleExample",
+    ),
+    fbandroid_compiler_flags = [
+        "-fexceptions",
+        "-frtti",
+    ],
+    platforms = (ANDROID, APPLE),
+    visibility = ["PUBLIC"],
+    deps = [
+        ":NativeCxxModuleExampleSpecJSI",
+    ],
+)
+
+rn_library(
+    name = "NativeCxxModuleExampleSpec",
+    srcs = glob(["NativeCxxModuleExample/*.js"]),
+    codegen_modules = True,
+    labels = [
+        "pfh:ReactNative_CommonInfrastructurePlaceholder",
+    ],
+    native_module_android_package_name = "com.facebook.fbreact.specs",
+    native_module_spec_name = "NativeCxxModuleExampleSpec",
+    visibility = ["PUBLIC"],
+    deps = [
+        "//xplat/js/RKJSModules/vendor/react:react",
+        "//xplat/js/react-native-github:react-native",
+    ],
+)

packages/rn-tester/NativeCxxModuleExample/NativeCxxModuleExample.cpp

@@ -0,0 +1,110 @@
+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#include "NativeCxxModuleExample.h"
+
+namespace facebook::react {
+
+NativeCxxModuleExample::NativeCxxModuleExample(
+    std::shared_ptr<CallInvoker> jsInvoker)
+    : NativeCxxModuleExampleCxxSpec(std::move(jsInvoker)) {}
+
+void NativeCxxModuleExample::getValueWithCallback(
+    jsi::Runtime &rt,
+    AsyncCallback<std::string> callback) {
+  callback({"value from callback!"});
+}
+
+std::vector<std::optional<ObjectStruct>> NativeCxxModuleExample::getArray(
+    jsi::Runtime &rt,
+    std::vector<std::optional<ObjectStruct>> arg) {
+  return arg;
+}
+
+bool NativeCxxModuleExample::getBool(jsi::Runtime &rt, bool arg) {
+  return arg;
+}
+
+ConstantsStruct NativeCxxModuleExample::getConstants(jsi::Runtime &rt) {
+  return ConstantsStruct{true, 69, "react-native"};
+}
+
+int32_t NativeCxxModuleExample::getEnum(jsi::Runtime &rt, int32_t arg) {
+  return arg;
+}
+
+std::map<std::string, std::optional<int32_t>> NativeCxxModuleExample::getMap(
+    jsi::Runtime &rt,
+    std::map<std::string, std::optional<int32_t>> arg) {
+  return arg;
+}
+
+double NativeCxxModuleExample::getNumber(jsi::Runtime &rt, double arg) {
+  return arg;
+}
+
+ObjectStruct NativeCxxModuleExample::getObject(
+    jsi::Runtime &rt,
+    ObjectStruct arg) {
+  return arg;
+}
+
+std::set<float> NativeCxxModuleExample::getSet(
+    jsi::Runtime &rt,
+    std::set<float> arg) {
+  return arg;
+}
+
+std::string NativeCxxModuleExample::getString(
+    jsi::Runtime &rt,
+    std::string arg) {
+  return arg;
+}
+
+std::string NativeCxxModuleExample::getUnion(
+    jsi::Runtime &rt,
+    float x,
+    std::string y,
+    jsi::Object z) {
+  std::string result = "x: " + std::to_string(x) + ", y: " + y + ", z: { ";
+  if (z.hasProperty(rt, "value")) {
+    result += "value: ";
+    result += std::to_string(z.getProperty(rt, "value").getNumber());
+  } else if (z.hasProperty(rt, "low")) {
+    result += "low: ";
+    result += z.getProperty(rt, "low").getString(rt).utf8(rt);
+  }
+  result += " }";
+  return result;
+}
+
+ValueStruct NativeCxxModuleExample::getValue(
+    jsi::Runtime &rt,
+    double x,
+    std::string y,
+    ObjectStruct z) {
+  ValueStruct result{x, y, z};
+  return result;
+}
+
+AsyncPromise<std::string> NativeCxxModuleExample::getValueWithPromise(
+    jsi::Runtime &rt,
+    bool error) {
+  auto promise = AsyncPromise<std::string>(rt, jsInvoker_);
+  if (error) {
+    promise.reject("intentional promise rejection");
+  } else {
+    promise.resolve("result!");
+  }
+  return promise;
+}
+
+void NativeCxxModuleExample::voidFunc(jsi::Runtime &rt) {
+  // Nothing to do
+}
+
+} // namespace facebook::react

packages/rn-tester/NativeCxxModuleExample/NativeCxxModuleExample.h

@@ -0,0 +1,66 @@
+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#pragma once
+
+#if __has_include(<React-Codegen/AppSpecsJSI.h>)
+#include <React-Codegen/AppSpecsJSI.h>
+#else
+#include <NativeCxxModuleExampleSpec/NativeCxxModuleExampleSpecJSI.h>
+#endif
+#include <memory>
+#include <set>
+#include <string>
+#include <vector>
+#include "NativeCxxModuleExample_ConstantsStruct.h"
+#include "NativeCxxModuleExample_ObjectStruct.h"
+#include "NativeCxxModuleExample_ValueStruct.h"
+
+namespace facebook::react {
+
+class NativeCxxModuleExample
+    : public NativeCxxModuleExampleCxxSpec<NativeCxxModuleExample> {
+ public:
+  NativeCxxModuleExample(std::shared_ptr<CallInvoker> jsInvoker);
+
+  void getValueWithCallback(
+      jsi::Runtime &rt,
+      AsyncCallback<std::string> callback);
+
+  std::vector<std::optional<ObjectStruct>> getArray(
+      jsi::Runtime &rt,
+      std::vector<std::optional<ObjectStruct>> arg);
+
+  bool getBool(jsi::Runtime &rt, bool arg);
+
+  ConstantsStruct getConstants(jsi::Runtime &rt);
+
+  int32_t getEnum(jsi::Runtime &rt, int32_t arg);
+
+  std::map<std::string, std::optional<int32_t>> getMap(
+      jsi::Runtime &rt,
+      std::map<std::string, std::optional<int32_t>> arg);
+
+  double getNumber(jsi::Runtime &rt, double arg);
+
+  ObjectStruct getObject(jsi::Runtime &rt, ObjectStruct arg);
+
+  std::set<float> getSet(jsi::Runtime &rt, std::set<float> arg);
+
+  std::string getString(jsi::Runtime &rt, std::string arg);
+
+  std::string getUnion(jsi::Runtime &rt, float x, std::string y, jsi::Object z);
+
+  ValueStruct
+  getValue(jsi::Runtime &rt, double x, std::string y, ObjectStruct z);
+
+  AsyncPromise<std::string> getValueWithPromise(jsi::Runtime &rt, bool error);
+
+  void voidFunc(jsi::Runtime &rt);
+};
+
+} // namespace facebook::react

packages/rn-tester/NativeCxxModuleExample/NativeCxxModuleExample.js

@@ -0,0 +1,61 @@
+/**
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *
+ * @flow strict-local
+ * @format
+ */
+
+import type {TurboModule} from 'react-native/Libraries/TurboModule/RCTExport';
+
+import {TurboModuleRegistry} from 'react-native';
+
+/** Flow enum support will be added when the sun rises in the west
+export enum EnumInt {
+  A = 23,
+  B = 42,
+}
+*/
+
+export type UnionFloat = 1.44 | 2.88 | 5.76;
+export type UnionString = 'One' | 'Two' | 'Three';
+export type UnionObject = {value: number} | {low: string};
+
+export type ObjectStruct = $ReadOnly<{
+  a: number,
+  b: string,
+  c?: ?string,
+}>;
+
+export type ValueStruct = $ReadOnly<{
+  x: number,
+  y: string,
+  z: ObjectStruct,
+}>;
+
+export interface Spec extends TurboModule {
+  +getArray: (arg: Array<ObjectStruct | null>) => Array<ObjectStruct | null>;
+  +getBool: (arg: boolean) => boolean;
+  +getConstants: () => {|
+    const1: boolean,
+    const2: number,
+    const3: string,
+  |};
+  +getEnum: (arg: number /*EnumInt*/) => number /*EnumInt*/;
+  +getMap: (arg: {[key: string]: ?number}) => {[key: string]: ?number};
+  +getNumber: (arg: number) => number;
+  +getObject: (arg: ObjectStruct) => ObjectStruct;
+  +getSet: (arg: Array<number>) => Array<number>;
+  +getString: (arg: string) => string;
+  +getUnion: (x: UnionFloat, y: UnionString, z: UnionObject) => string;
+  +getValue: (x: number, y: string, z: ObjectStruct) => ObjectStruct;
+  +getValueWithCallback: (callback: (value: string) => void) => void;
+  +getValueWithPromise: (error: boolean) => Promise<string>;
+  +voidFunc: () => void;
+}
+
+export default (TurboModuleRegistry.get<Spec>(
+  'NativeCxxModuleExampleCxx',
+): ?Spec);

packages/rn-tester/NativeCxxModuleExample/NativeCxxModuleExample.podspec

@@ -0,0 +1,38 @@
+# Copyright (c) Meta Platforms, Inc. and affiliates.
+#
+# This source code is licensed under the MIT license found in the
+# LICENSE file in the root directory of this source tree.
+
+require "json"
+
+package = JSON.parse(File.read(File.join(__dir__, "../package.json")))
+
+Pod::Spec.new do |s|
+  s.name            = "NativeCxxModuleExample"
+  s.version         = package["version"]
+  s.summary         = package["description"]
+  s.description     = "NativeCxxModuleExample"
+  s.homepage        = "https://github.com/facebook/react-native.git"
+  s.license         = "MIT"
+  s.platforms       = { :ios => "12.4" }
+  s.compiler_flags  = '-Wno-nullability-completeness'
+  s.author          = "Meta Platforms, Inc. and its affiliates"
+  s.source          = { :git => "https://github.com/facebook/react-native.git", :tag => "#{s.version}" }
+  s.source_files    = "**/*.{h,cpp}"
+  s.requires_arc    = true
+  s.pod_target_xcconfig = {
+    "USE_HEADERMAP" => "YES",
+    "CLANG_CXX_LANGUAGE_STANDARD" => "c++17"
+  }
+
+  install_modules_dependencies(s)
+
+  s.dependency "ReactCommon/turbomodule/core"
+
+  # Enable codegen for this library
+  use_react_native_codegen!(s, {
+    :react_native_path => "../../..",
+    :js_srcs_dir => "./",
+    :library_type => "modules",
+  })
+end

packages/rn-tester/NativeCxxModuleExample/NativeCxxModuleExample_ConstantsStruct.h

@@ -0,0 +1,37 @@
+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+#pragma once
+
+#include <react/bridging/Bridging.h>
+#include <optional>
+#include <string>
+
+namespace facebook::react {
+
+struct ConstantsStruct {
+  bool const1;
+  int32_t const2;
+  std::string const3;
+  bool operator==(const ConstantsStruct &other) const {
+    return const1 == other.const1 && const2 == other.const2 &&
+        const3 == other.const3;
+  }
+};
+
+template <>
+struct Bridging<ConstantsStruct> {
+  static jsi::Object toJs(jsi::Runtime &rt, const ConstantsStruct &value) {
+    auto result = facebook::jsi::Object(rt);
+    result.setProperty(rt, "const1", bridging::toJs(rt, value.const1));
+    result.setProperty(rt, "const2", bridging::toJs(rt, value.const2));
+    result.setProperty(rt, "const3", bridging::toJs(rt, value.const3));
+    return result;
+  }
+};
+
+} // namespace facebook::react