Integrate Native Module codegen into Xcode build pipeline (#30449)

Summary:
Move the codegen invocation out of Podfiles and into the FBReactNativeSpec Pod itself. With this change, developers do not need to modify their existing project's Podfiles, and yet the codegen will be integrated into their projects automatically by way of the FBReactNativeSpec Pod.

This is accomplished in part by injecting a script build phase into the Pods Xcode project that is generated by CocoaPods. The build phase will be executed if the generated FBReactNativeSpec{.h, -generated.mm} files are not present, or if the contents of the Libraries directory has changed. The codegen is also triggered by `pod install` via `prepare_command`.

The codegen will thus be invoked in these situations:

**RNTester:**
* When `pod install` is invoked in `packages/rn-tester/` (`prepare_command`)
* When `packages/rn-tester/RNTesterPods.xcworkspace` is built, if the output files are not present or if the input files have changed (`script_phase`).

**OSS React Native apps:**
* When `pod install` is invoked in `ios/` (`prepare_command`)
* When `ios/AwesomeProject.xcworkspace` is built, if the output files are not present or if the input files have changed (`script_phase`).

Pull Request resolved: #30449

Changelog: [Internal] - Moved codegen invocation out of Podfile and into FBReactNativeSpec Pod

Differential Revision: D25138896

fbshipit-source-id: c756ea2f98189735343b7769bc5022379371906e

Libraries/FBReactNativeSpec/FBReactNativeSpec.podspec

@@ -9,13 +9,20 @@ package = JSON.parse(File.read(File.join(__dir__, "..", "..", "package.json")))
 version = package['version']
 
 source = { :git => 'https://github.com/facebook/react-native.git' }
+codegenPathPrefix = ".."
 if version == '1000.0.0'
   # This is an unpublished version, use the latest commit hash of the react-native repo, which we’re presumably in.
   source[:commit] = `git rev-parse HEAD`.strip
+  codegenPathPrefix = "packages"
 else
   source[:tag] = "v#{version}"
 end
 
+reactNativePath = File.join(__dir__, "..", "..")
+codegenScriptPath = File.join(reactNativePath, "scripts", "generate_native_modules_specs.rb")
+codegenPath = File.join(reactNativePath, codegenPathPrefix, "react-native-codegen")
+codegenCommand = "CODEGEN_PATH=#{codegenPath} ruby '#{codegenScriptPath}'"
+
 folly_compiler_flags = '-DFOLLY_NO_CONFIG -DFOLLY_MOBILE=1 -DFOLLY_USE_LIBCPP=1 -Wno-comma -Wno-shorten-64-to-32'
 folly_version = '2020.01.13.00'
 
@@ -44,4 +51,13 @@ Pod::Spec.new do |s|
   s.dependency "React-Core", version
   s.dependency "React-jsi", version
   s.dependency "ReactCommon/turbomodule/core", version
+
+  s.prepare_command = codegenCommand
+  s.script_phase = {
+    :name => 'Generate Native Modules Code',
+    :input_files => [File.join(__dir__, "..")],
+    :output_files => [File.join(__dir__, "Libraries", "FBReactNativeSpec", "FBReactNativeSpec", "FBReactNativeSpec.h"), File.join(__dir__, "Libraries", "FBReactNativeSpec", "FBReactNativeSpec", "FBReactNativeSpec-generated.mm")],
+    :script => codegenCommand,
+    :execution_position => :before_compile
+  }
 end

package.json

@@ -38,6 +38,7 @@
     "README.md",
     "rn-get-polyfills.js",
     "scripts/compose-source-maps.js",
+    "scripts/generate_native_modules_specs.rb",
     "scripts/generate-native-modules-specs-cli.js",
     "scripts/ios-configure-glog.sh",
     "scripts/launchPackager.bat",

packages/rn-tester/Podfile

@@ -60,16 +60,6 @@ def frameworks_pre_install(installer)
   end
 end
 
-pre_install do |installer|
-  frameworks_pre_install(installer) if ENV['USE_FRAMEWORKS'] == '1'
-  if ENV['USE_CODEGEN'] != '0'
-    prefix_path = "../.."
-    codegen_path = "../../packages/react-native-codegen"
-    system("./#{codegen_path}/scripts/oss/build.sh") or raise "Could not build react-native-codegen package"
-    codegen_pre_install(installer, {path:prefix_path, codegen_path:codegen_path})
-  end
-end
-
 post_install do |installer|
   flipper_post_install(installer)
 end

packages/rn-tester/Podfile.lock

@@ -15,12 +15,12 @@ PODS:
     - Flipper-Folly (~> 2.2)
     - Flipper-RSocket (~> 1.1)
   - Flipper-DoubleConversion (1.1.7)
-  - Flipper-Folly (2.2.0):
+  - Flipper-Folly (2.3.0):
     - boost-for-react-native
     - CocoaLibEvent (~> 1.0)
     - Flipper-DoubleConversion
     - Flipper-Glog
-    - OpenSSL-Universal (= 1.0.2.19)
+    - OpenSSL-Universal (= 1.0.2.20)
   - Flipper-Glog (0.3.6)
   - Flipper-PeerTalk (0.0.4)
   - Flipper-RSocket (1.1.0):
@@ -58,9 +58,9 @@ PODS:
     - FlipperKit/Core
     - FlipperKit/FlipperKitNetworkPlugin
   - glog (0.3.5)
-  - OpenSSL-Universal (1.0.2.19):
-    - OpenSSL-Universal/Static (= 1.0.2.19)
-  - OpenSSL-Universal/Static (1.0.2.19)
+  - OpenSSL-Universal (1.0.2.20):
+    - OpenSSL-Universal/Static (= 1.0.2.20)
+  - OpenSSL-Universal/Static (1.0.2.20)
   - RCT-Folly (2020.01.13.00):
     - boost-for-react-native
     - DoubleConversion
@@ -490,16 +490,16 @@ SPEC CHECKSUMS:
   CocoaLibEvent: 2fab71b8bd46dd33ddb959f7928ec5909f838e3f
   DoubleConversion: cde416483dac037923206447da6e1454df403714
   FBLazyVector: fe973c09b2299b5e8154186ecf1f6554b4f70987
-  FBReactNativeSpec: 20a9345af9157362b51ab0258d842cb7bb347d19
+  FBReactNativeSpec: 5abf6676352b0b7cffaeef981408e4802bda23a2
   Flipper: be611d4b742d8c87fbae2ca5f44603a02539e365
   Flipper-DoubleConversion: 38631e41ef4f9b12861c67d17cb5518d06badc41
-  Flipper-Folly: c12092ea368353b58e992843a990a3225d4533c3
+  Flipper-Folly: e4493b013c02d9347d5e0cb4d128680239f6c78a
   Flipper-Glog: 1dfd6abf1e922806c52ceb8701a3599a79a200a6
   Flipper-PeerTalk: 116d8f857dc6ef55c7a5a75ea3ceaafe878aadc9
   Flipper-RSocket: 64e7431a55835eb953b0bf984ef3b90ae9fdddd7
   FlipperKit: ab353d41aea8aae2ea6daaf813e67496642f3d7d
   glog: 40a13f7840415b9a77023fbcae0f1e6f43192af3
-  OpenSSL-Universal: 8b48cc0d10c1b2923617dfe5c178aa9ed2689355
+  OpenSSL-Universal: ff34003318d5e1163e9529b08470708e389ffcdd
   RCT-Folly: b39288cedafe50da43317ec7d91bcc8cc0abbf33
   RCTRequired: d3d4ce60e1e2282864d7560340690a3c8c646de1
   RCTTypeSafety: 4da4f9f218727257c50fd3bf2683a06cdb4fede3
@@ -528,6 +528,6 @@ SPEC CHECKSUMS:
   Yoga: 69ef0b2bba5387523f793957a9f80dbd61e89631
   YogaKit: f782866e155069a2cca2517aafea43200b01fd5a
 
-PODFILE CHECKSUM: cd671238f92c51cd349a1c778fd089994174b101
+PODFILE CHECKSUM: 3adfe268d800503789170d1862bde422ee204fe8
 
 COCOAPODS: 1.10.0

scripts/generate_native_modules_specs.rb

@@ -0,0 +1,34 @@
+#!/usr/bin/ruby
+# Copyright (c) Facebook, Inc. and its affiliates.
+#
+# This source code is licensed under the MIT license found in the
+# LICENSE file in the root directory of this source tree.
+
+require 'tmpdir'
+
+# Handle Core Modules
+def codegen_core_modules(codegenPath)
+  reactNativePath = File.join(__dir__, "..")
+  srcsDir = File.join(reactNativePath, "Libraries")
+  libraryName = "FBReactNativeSpec"
+  outputDir = File.join(srcsDir, libraryName, libraryName)
+
+  codegen(codegenPath, srcsDir, libraryName, outputDir)
+end
+
+def codegen(codegenPath, srcsDir, libraryName, outputDir)
+  Dir.mktmpdir do |dir|
+    schemaFilePath = File.join(dir, "schema-#{libraryName}.json")
+    combineCliPath = File.join(codegenPath, "lib", "cli", "combine", "combine-js-to-schema-cli.js")
+    generateSpecsCliPath = File.join(__dir__, "generate-native-modules-specs-cli.js")
+    system("node #{combineCliPath} #{schemaFilePath} #{srcsDir}") or raise "Could not generate Native Module schema"
+    system("node #{generateSpecsCliPath} ios #{schemaFilePath} #{outputDir} #{libraryName}") or raise "Could not generate code for #{libraryName}"
+  end
+end
+
+def main()
+  codegenPath = ENV["CODEGEN_PATH"] ||= File.join(reactNativePath, "..", "react-native-codegen")
+  codegen_core_modules(codegenPath)
+end
+
+main()

scripts/react_native_pods.rb

@@ -108,21 +108,3 @@ def flipper_post_install(installer)
     end
   end
 end
-
-# Pre Install processing for Native Modules
-def codegen_pre_install(installer, options={})
-  # Path to React Native
-  prefix = options[:path] ||= "../node_modules/react-native"
-
-  # Path to react-native-codegen
-  codegen_path = options[:codegen_path] ||= "#{prefix}/../react-native-codegen"
-
-  # Handle Core Modules
-  Dir.mktmpdir do |dir|
-    native_module_spec_name = "FBReactNativeSpec"
-    schema_file = dir + "/schema-#{native_module_spec_name}.json"
-    srcs_dir = "#{prefix}/Libraries"
-    schema_generated = system("node #{codegen_path}/lib/cli/combine/combine-js-to-schema-cli.js #{schema_file} #{srcs_dir}") or raise "Could not generate Native Module schema"
-    specs_generated = system("node #{prefix}/scripts/generate-native-modules-specs-cli.js ios #{schema_file} #{srcs_dir}/#{native_module_spec_name}/#{native_module_spec_name}") or raise "Could not generate code for #{native_module_spec_name}"
-  end
-end

template/ios/Podfile

@@ -13,10 +13,6 @@ target 'HelloWorld' do
     # Pods for testing
   end
 
-  pre_install do |installer|
-    codegen_pre_install(installer)
-  end
-
   # Enables Flipper.
   #
   # Note that if you have use_frameworks! enabled, Flipper will not work and