WIP.

js/commonjs_export.js

+/**
+ * @fileoverview Export symbols needed by generated code in CommonJS style.
+ */
+
+exports = {
+  Message: jspb.Message,
+  BinaryReader: jspb.BinaryReader,
+  BinaryWriter: jspb.BinaryWriter,
+  ExtensionFieldInfo: jspb.ExtensionFieldInfo,
+};

js/gulpfile.js

 var gulp = require('gulp');
 var exec = require('child_process').exec;
 
-gulp.task('genproto', function (cb) {
+gulp.task('genproto_closure', function (cb) {
   exec('../src/protoc --js_out=library=testproto_libs,binary:. -I ../src -I . *.proto ../src/google/protobuf/descriptor.proto',
        function (err, stdout, stderr) {
     console.log(stdout);
     console.log(stderr);
     cb(err);
   });
-})
+});
+
+gulp.task('genproto_commonjs', function (cb) {
+  exec('mkdir -p commonjs_out && ../src/protoc --js_out=import_style=commonjs,binary:commonjs_out -I ../src -I . *.proto ../src/google/protobuf/descriptor.proto',
+       function (err, stdout, stderr) {
+    console.log(stdout);
+    console.log(stderr);
+    cb(err);
+  });
+});
 
-gulp.task('deps', ['genproto'], function (cb) {
+gulp.task('dist', function (cb) {
+  // TODO(haberman): minify this more aggressively.
+  // Will require proper externs/exports.
+  exec('./node_modules/google-closure-library/closure/bin/calcdeps.py -i message.js -i binary/reader.js -i binary/writer.js -p . -p node_modules/google-closure-library/closure -o compiled --compiler_jar node_modules/google-closure-compiler/compiler.jar > google-protobuf.js',
+       function (err, stdout, stderr) {
+    console.log(stdout);
+    console.log(stderr);
+    cb(err);
+  });
+});
+
+gulp.task('deps', ['genproto_closure'], function (cb) {
   exec('./node_modules/google-closure-library/closure/bin/build/depswriter.py *.js binary/*.js > deps.js',
        function (err, stdout, stderr) {
     console.log(stdout);
     console.log(stderr);
     cb(err);
   });
-})
+});
 
-gulp.task('test', ['genproto', 'deps'], function (cb) {
+gulp.task('test_closure', ['genproto_closure', 'deps'], function (cb) {
   exec('JASMINE_CONFIG_PATH=jasmine.json ./node_modules/.bin/jasmine',
        function (err, stdout, stderr) {
     console.log(stdout);
@@ -27,3 +47,12 @@ gulp.task('test', ['genproto', 'deps'], function (cb) {
     cb(err);
   });
 });
+
+gulp.task('test_commonjs', ['genproto_commonjs', 'dist'], function (cb) {
+  exec('JASMINE_CONFIG_PATH=jasmine.json cp jasmine_commonjs.json commonjs_out/jasmine.json && cd commonjs_out && ../node_modules/.bin/jasmine',
+       function (err, stdout, stderr) {
+    console.log(stdout);
+    console.log(stderr);
+    cb(err);
+  });
+});

js/jasmine_commonjs.json

+{
+    "spec_dir": "",
+    "spec_files": [
+        "*_test.js"
+    ],
+    "helpers": [
+        "node_modules/google-closure-library/closure/goog/bootstrap/nodejs.js",
+        "node_loader.js",
+        "deps.js"
+    ]
+}

js/package.json

@@ -2,13 +2,15 @@
   "name": "google-protobuf",
   "version": "3.0.0-alpha.5",
   "description": "Protocol Buffers for JavaScript",
-  "main": "debug.js",
+  "main": "google-protobuf.js",
   "dependencies": {
     "google-closure-library": "~20160125.0.0",
     "gulp": "~3.9.0",
     "jasmine": "~2.4.1"
   },
-  "devDependencies": {},
+  "devDependencies": {
+    "google-closure-compiler": "~20151216.2.0"
+  },
   "scripts": {
     "test": "./node_modules/gulp/bin/gulp.js test"
   },

src/google/protobuf/compiler/js/js_generator.h

@@ -67,6 +67,13 @@ struct GeneratorOptions {
   bool error_on_name_conflict;
   // Enable binary-format support?
   bool binary;
+  // What style of imports should be used.
+  enum ImportStyle {
+    IMPORT_CLOSURE,    // goog.require()
+    IMPORT_COMMONJS,   // require()
+    IMPORT_BROWSER,    // no import statements
+    IMPORT_ES6,        // import { member } from ''
+  } import_style;
 
   GeneratorOptions()
       : add_require_for_enums(false),
@@ -75,7 +82,8 @@ struct GeneratorOptions {
         namespace_prefix(""),
         library(""),
         error_on_name_conflict(false),
-        binary(false) {}
+        binary(false),
+        import_style(IMPORT_CLOSURE) {}
 
   bool ParseFromOptions(
       const vector< pair< string, string > >& options,
@@ -111,6 +119,10 @@ class LIBPROTOC_EXPORT Generator : public CodeGenerator {
                     io::Printer* printer,
                     const vector<const FileDescriptor*>& file,
                     std::set<string>* provided) const;
+  void FindProvidesForFile(const GeneratorOptions& options,
+                           io::Printer* printer,
+                           const FileDescriptor* file,
+                           std::set<string>* provided) const;
   void FindProvidesForMessage(const GeneratorOptions& options,
                               io::Printer* printer,
                               const Descriptor* desc,
@@ -168,6 +180,10 @@ class LIBPROTOC_EXPORT Generator : public CodeGenerator {
                                 std::set<string>* required,
                                 std::set<string>* forwards) const;
 
+  void GenerateFile(const GeneratorOptions& options,
+                    io::Printer* printer,
+                    const FileDescriptor* file) const;
+
   // Generate definitions for all message classes and enums in all files,
   // processing the files in dependence order.
   void GenerateFilesInDepOrder(const GeneratorOptions& options,