Add EventEmitter Code-gen support for Java and ObjC Turbo Modules

packages/react-native-codegen/src/generators/modules/GenerateModuleJavaSpec.js

@@ -12,6 +12,7 @@
 
 import type {
   NamedShape,
+  NativeModuleEventEmitterShape,
   NativeModuleFunctionTypeAnnotation,
   NativeModuleParamTypeAnnotation,
   NativeModulePropertyShape,
@@ -23,6 +24,7 @@ import type {AliasResolver} from './Utils';
 
 const {unwrapNullable} = require('../../parsers/parsers-commons');
 const {wrapOptional} = require('../TypeUtils/Java');
+const {toPascalCase} = require('../Utils');
 const {createAliasResolver, getModules} = require('./Utils');
 
 type FilesOutput = Map<string, string>;
@@ -32,11 +34,13 @@ function FileTemplate(
     packageName: string,
     className: string,
     jsName: string,
+    eventEmitters: string,
     methods: string,
     imports: string,
   }>,
 ): string {
-  const {packageName, className, jsName, methods, imports} = config;
+  const {packageName, className, jsName, eventEmitters, methods, imports} =
+    config;
   return `
 /**
  * This code was generated by [react-native-codegen](https://www.npmjs.com/package/react-native-codegen).
@@ -65,11 +69,28 @@ public abstract class ${className} extends ReactContextBaseJavaModule implements
     return NAME;
   }
 
-${methods}
+${eventEmitters}${eventEmitters.length > 0 ? '\n\n' : ''}${methods}
 }
 `;
 }
 
+function EventEmitterTemplate(
+  eventEmitter: NativeModuleEventEmitterShape,
+  imports: Set<string>,
+): string {
+  return `  protected final void emit${toPascalCase(eventEmitter.name)}(${
+    eventEmitter.typeAnnotation.typeAnnotation.type !== 'VoidTypeAnnotation'
+      ? `${translateEventEmitterTypeToJavaType(eventEmitter, imports)} value`
+      : ''
+  }) {
+    mEventEmitterCallback.invoke("${eventEmitter.name}"${
+    eventEmitter.typeAnnotation.typeAnnotation.type !== 'VoidTypeAnnotation'
+      ? ', value'
+      : ''
+  });
+  }`;
+}
+
 function MethodTemplate(
   config: $ReadOnly<{
     abstract: boolean,
@@ -102,6 +123,34 @@ function MethodTemplate(
 
 type Param = NamedShape<Nullable<NativeModuleParamTypeAnnotation>>;
 
+function translateEventEmitterTypeToJavaType(
+  eventEmitter: NativeModuleEventEmitterShape,
+  imports: Set<string>,
+): string {
+  switch (eventEmitter.typeAnnotation.typeAnnotation.type) {
+    case 'StringTypeAnnotation':
+      return 'String';
+    case 'NumberTypeAnnotation':
+    case 'FloatTypeAnnotation':
+    case 'DoubleTypeAnnotation':
+    case 'Int32TypeAnnotation':
+      return 'double';
+    case 'BooleanTypeAnnotation':
+      return 'boolean';
+    case 'ObjectTypeAnnotation':
+    case 'TypeAliasTypeAnnotation':
+      imports.add('com.facebook.react.bridge.ReadableMap');
+      return 'ReadableMap';
+    case 'ArrayTypeAnnotation':
+      imports.add('com.facebook.react.bridge.ReadableArray');
+      return 'ReadableArray';
+    default:
+      throw new Error(
+        `Unsupported eventType for ${eventEmitter.name}. Found: ${eventEmitter.typeAnnotation.typeAnnotation.type}`,
+      );
+  }
+}
+
 function translateFunctionParamToJavaType(
   param: Param,
   createErrorMessage: (typeName: string) => string,
@@ -533,6 +582,9 @@ module.exports = {
           packageName: normalizedPackageName,
           className,
           jsName: moduleName,
+          eventEmitters: spec.eventEmitters
+            .map(eventEmitter => EventEmitterTemplate(eventEmitter, imports))
+            .join('\n\n'),
           methods: methods.filter(Boolean).join('\n\n'),
           imports: Array.from(imports)
             .sort()

packages/react-native-codegen/src/generators/modules/GenerateModuleJniCpp.js

@@ -12,6 +12,7 @@
 
 import type {
   NamedShape,
+  NativeModuleEventEmitterShape,
   NativeModuleFunctionTypeAnnotation,
   NativeModuleParamTypeAnnotation,
   NativeModulePropertyShape,
@@ -54,9 +55,11 @@ const HostFunctionTemplate = ({
 
 const ModuleClassConstructorTemplate = ({
   hasteModuleName,
+  eventEmitters,
   methods,
 }: $ReadOnly<{
   hasteModuleName: string,
+  eventEmitters: $ReadOnlyArray<NativeModuleEventEmitterShape>,
   methods: $ReadOnlyArray<{
     propertyName: string,
     argCount: number,
@@ -69,7 +72,21 @@ ${methods
   .map(({propertyName, argCount}) => {
     return `  methodMap_["${propertyName}"] = MethodMetadata {${argCount}, __hostFunction_${hasteModuleName}SpecJSI_${propertyName}};`;
   })
-  .join('\n')}
+  .join('\n')}${
+    eventEmitters.length > 0
+      ? eventEmitters
+          .map(eventEmitter => {
+            return `
+  eventEmitterMap_["${eventEmitter.name}"] = std::make_shared<AsyncEventEmitter<folly::dynamic>>();`;
+          })
+          .join('')
+      : ''
+  }${
+    eventEmitters.length > 0
+      ? `
+  setEventEmitterCallback(params.instance);`
+      : ''
+  }
 }`.trim();
 };
 
@@ -438,7 +455,7 @@ module.exports = {
       .map(hasteModuleName => {
         const {
           aliasMap,
-          spec: {methods},
+          spec: {eventEmitters, methods},
         } = nativeModules[hasteModuleName];
         const resolveAlias = createAliasResolver(aliasMap);
 
@@ -457,6 +474,7 @@ module.exports = {
           '\n\n' +
           ModuleClassConstructorTemplate({
             hasteModuleName,
+            eventEmitters,
             methods: methods
               .map(({name: propertyName, typeAnnotation}) => {
                 const [{returnTypeAnnotation, params}] =

packages/react-native-codegen/src/generators/modules/GenerateModuleObjCpp/index.js

@@ -15,6 +15,7 @@ import type {MethodSerializationOutput} from './serializeMethod';
 
 const {createAliasResolver, getModules} = require('../Utils');
 const {serializeStruct} = require('./header/serializeStruct');
+const {EventEmitterHeaderTemplate} = require('./serializeEventEmitter');
 const {serializeMethod} = require('./serializeMethod');
 const {serializeModuleSource} = require('./source/serializeModule');
 const {StructCollector} = require('./StructCollector');
@@ -24,17 +25,24 @@ type FilesOutput = Map<string, string>;
 const ModuleDeclarationTemplate = ({
   hasteModuleName,
   structDeclarations,
+  eventEmitters,
   protocolMethods,
 }: $ReadOnly<{
   hasteModuleName: string,
   structDeclarations: string,
+  eventEmitters: string,
   protocolMethods: string,
 }>) => `${structDeclarations}
 @protocol ${hasteModuleName}Spec <RCTBridgeModule, RCTTurboModule>
 
 ${protocolMethods}
 
 @end
+
+@interface ${hasteModuleName}Spec : RCTTurboModule
+${eventEmitters}
+@end
+
 namespace facebook::react {
   /**
    * ObjC++ class for module '${hasteModuleName}'
@@ -187,6 +195,9 @@ module.exports = {
         ModuleDeclarationTemplate({
           hasteModuleName: hasteModuleName,
           structDeclarations: structStrs.join('\n'),
+          eventEmitters: spec.eventEmitters
+            .map(eventEmitter => EventEmitterHeaderTemplate(eventEmitter))
+            .join('\n'),
           protocolMethods: methodSerializations
             .map(({protocolMethod}) => protocolMethod)
             .join('\n'),
@@ -199,6 +210,8 @@ module.exports = {
         serializeModuleSource(
           hasteModuleName,
           generatedStructs,
+          hasteModuleName,
+          spec.eventEmitters,
           methodSerializations.filter(
             ({selector}) => selector !== '@selector(constantsToExport)',
           ),

packages/react-native-codegen/src/generators/modules/GenerateModuleObjCpp/serializeEventEmitter.js

@@ -0,0 +1,70 @@
+/**
+ * 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
+ * @format
+ */
+
+import type {NativeModuleEventEmitterShape} from '../../../CodegenSchema';
+
+const {toPascalCase} = require('../../Utils');
+
+function getEventEmitterTypeObjCType(
+  eventEmitter: NativeModuleEventEmitterShape,
+): string {
+  switch (eventEmitter.typeAnnotation.typeAnnotation.type) {
+    case 'StringTypeAnnotation':
+      return 'NSString *';
+    case 'NumberTypeAnnotation':
+      return 'NSNumber *';
+    case 'BooleanTypeAnnotation':
+      return 'BOOL';
+    case 'ObjectTypeAnnotation':
+    case 'TypeAliasTypeAnnotation':
+      return 'NSDictionary *';
+    case 'ArrayTypeAnnotation':
+      return 'NSArray<id<NSObject>> *';
+    default:
+      throw new Error(
+        `Unsupported eventType for ${eventEmitter.name}. Found: ${eventEmitter.typeAnnotation.typeAnnotation.type}`,
+      );
+  }
+}
+
+function EventEmitterHeaderTemplate(
+  eventEmitter: NativeModuleEventEmitterShape,
+): string {
+  return `- (void)emit${toPascalCase(eventEmitter.name)}${
+    eventEmitter.typeAnnotation.typeAnnotation.type !== 'VoidTypeAnnotation'
+      ? `:(${getEventEmitterTypeObjCType(eventEmitter)})value`
+      : ''
+  };`;
+}
+
+function EventEmitterImplementationTemplate(
+  eventEmitter: NativeModuleEventEmitterShape,
+): string {
+  return `- (void)emit${toPascalCase(eventEmitter.name)}${
+    eventEmitter.typeAnnotation.typeAnnotation.type !== 'VoidTypeAnnotation'
+      ? `:(${getEventEmitterTypeObjCType(eventEmitter)})value`
+      : ''
+  }
+{
+  _eventEmitterCallback("${eventEmitter.name}", ${
+    eventEmitter.typeAnnotation.typeAnnotation.type !== 'VoidTypeAnnotation'
+      ? eventEmitter.typeAnnotation.typeAnnotation.type !==
+        'BooleanTypeAnnotation'
+        ? 'value'
+        : '[NSNumber numberWithBool:value]'
+      : 'nil'
+  });
+}`;
+}
+
+module.exports = {
+  EventEmitterHeaderTemplate,
+  EventEmitterImplementationTemplate,
+};

packages/react-native-codegen/src/generators/modules/GenerateModuleObjCpp/source/serializeModule.js

@@ -10,21 +10,37 @@
 
 'use strict';
 
+import type {NativeModuleEventEmitterShape} from '../../../../CodegenSchema';
 import type {
   MethodSerializationOutput,
   StructParameterRecord,
 } from '../serializeMethod';
 import type {Struct} from '../StructCollector';
 
+const {
+  EventEmitterImplementationTemplate,
+} = require('./../serializeEventEmitter');
+
 const ModuleTemplate = ({
   hasteModuleName,
   structs,
+  moduleName,
+  eventEmitters,
   methodSerializationOutputs,
 }: $ReadOnly<{
   hasteModuleName: string,
   structs: $ReadOnlyArray<Struct>,
+  moduleName: string,
+  eventEmitters: $ReadOnlyArray<NativeModuleEventEmitterShape>,
   methodSerializationOutputs: $ReadOnlyArray<MethodSerializationOutput>,
-}>) => `${structs
+}>) => `
+@implementation ${hasteModuleName}Spec
+${eventEmitters
+  .map(eventEmitter => EventEmitterImplementationTemplate(eventEmitter))
+  .join('\n')}
+@end
+
+${structs
   .map(struct =>
     RCTCxxConvertCategoryTemplate({hasteModuleName, structName: struct.name}),
   )
@@ -52,7 +68,23 @@ namespace facebook::react {
             argCount,
           }),
         )
-        .join('\n' + ' '.repeat(8))}
+        .join('\n' + ' '.repeat(8))}${
+  eventEmitters.length > 0
+    ? eventEmitters
+        .map(eventEmitter => {
+          return `
+        eventEmitterMap_["${eventEmitter.name}"] = std::make_shared<AsyncEventEmitter<id>>();`;
+        })
+        .join('')
+    : ''
+}${
+  eventEmitters.length > 0
+    ? `
+        setEventEmitterCallback([&](const std::string &name, id value) {
+          static_cast<AsyncEventEmitter<id> &>(*eventEmitterMap_[name]).emit(value);
+        });`
+    : ''
+}
   }
 } // namespace facebook::react`;
 
@@ -105,11 +137,15 @@ const MethodMapEntryTemplate = ({
 function serializeModuleSource(
   hasteModuleName: string,
   structs: $ReadOnlyArray<Struct>,
+  moduleName: string,
+  eventEmitters: $ReadOnlyArray<NativeModuleEventEmitterShape>,
   methodSerializationOutputs: $ReadOnlyArray<MethodSerializationOutput>,
 ): string {
   return ModuleTemplate({
     hasteModuleName,
     structs: structs.filter(({context}) => context !== 'CONSTANTS'),
+    moduleName,
+    eventEmitters,
     methodSerializationOutputs,
   });
 }