Revert "Update grpc protoc plugin to be compliant of proto3 field presence"

.gitmodules

@@ -8,6 +8,7 @@
 [submodule "third_party/protobuf"]
 	path = third_party/protobuf
 	url = https://github.com/google/protobuf.git
+	branch = 3.0.x
 [submodule "third_party/gflags"]
 	path = third_party/gflags
 	url = https://github.com/gflags/gflags.git

bazel/grpc_deps.bzl

@@ -154,11 +154,11 @@ def grpc_deps():
     if "com_google_protobuf" not in native.existing_rules():
         http_archive(
             name = "com_google_protobuf",
-            sha256 = "efaf69303e01caccc2447064fc1832dfd23c0c130df0dc5fc98a13185bb7d1a7",
-            strip_prefix = "protobuf-678da4f76eb9168c9965afc2149944a66cd48546",
+            sha256 = "2435b7fb83b8a608c24ca677907aa9a35e482a7f018e65ca69481b3c8c9f7caf",
+            strip_prefix = "protobuf-d0bfd5221182da1a7cc280f3337b5e41a89539cf",
             urls = [
-                "https://storage.googleapis.com/grpc-bazel-mirror/github.com/google/protobuf/archive/678da4f76eb9168c9965afc2149944a66cd48546.tar.gz",
-                "https://github.com/google/protobuf/archive/678da4f76eb9168c9965afc2149944a66cd48546.tar.gz",
+                "https://storage.googleapis.com/grpc-bazel-mirror/github.com/google/protobuf/archive/d0bfd5221182da1a7cc280f3337b5e41a89539cf.tar.gz",
+                "https://github.com/google/protobuf/archive/d0bfd5221182da1a7cc280f3337b5e41a89539cf.tar.gz",
             ],
         )
 

grpc.gemspec

@@ -32,7 +32,7 @@ Gem::Specification.new do |s|
   s.require_paths = %w( src/ruby/lib src/ruby/bin src/ruby/pb )
   s.platform      = Gem::Platform::RUBY
 
-  s.add_dependency 'google-protobuf', '~> 3.12'
+  s.add_dependency 'google-protobuf', '~> 3.11'
   s.add_dependency 'googleapis-common-protos-types', '~> 1.0'
 
   s.add_development_dependency 'bundler',            '>= 1.9'

src/compiler/cpp_plugin.h

@@ -34,14 +34,10 @@ class CppGrpcGenerator : public grpc::protobuf::compiler::CodeGenerator {
   CppGrpcGenerator() {}
   virtual ~CppGrpcGenerator() {}
 
-  uint64_t GetSupportedFeatures() const override {
-    return FEATURE_PROTO3_OPTIONAL;
-  }
-
   virtual bool Generate(const grpc::protobuf::FileDescriptor* file,
                         const grpc::string& parameter,
                         grpc::protobuf::compiler::GeneratorContext* context,
-                        grpc::string* error) const override {
+                        grpc::string* error) const {
     if (file->options().cc_generic_services()) {
       *error =
           "cpp grpc proto compiler plugin does not work with generic "

src/compiler/csharp_plugin.cc

@@ -29,14 +29,10 @@ class CSharpGrpcGenerator : public grpc::protobuf::compiler::CodeGenerator {
   CSharpGrpcGenerator() {}
   ~CSharpGrpcGenerator() {}
 
-  uint64_t GetSupportedFeatures() const override {
-    return FEATURE_PROTO3_OPTIONAL;
-  }
-
   bool Generate(const grpc::protobuf::FileDescriptor* file,
                 const grpc::string& parameter,
                 grpc::protobuf::compiler::GeneratorContext* context,
-                grpc::string* error) const override {
+                grpc::string* error) const {
     std::vector<std::pair<grpc::string, grpc::string> > options;
     grpc::protobuf::compiler::ParseGeneratorParameter(parameter, &options);
 

src/compiler/node_plugin.cc

@@ -32,14 +32,10 @@ class NodeGrpcGenerator : public grpc::protobuf::compiler::CodeGenerator {
   NodeGrpcGenerator() {}
   ~NodeGrpcGenerator() {}
 
-  uint64_t GetSupportedFeatures() const override {
-    return FEATURE_PROTO3_OPTIONAL;
-  }
-
   bool Generate(const grpc::protobuf::FileDescriptor* file,
                 const grpc::string& parameter,
                 grpc::protobuf::compiler::GeneratorContext* context,
-                grpc::string* error) const override {
+                grpc::string* error) const {
     grpc_node_generator::Parameters generator_parameters;
     generator_parameters.minimum_node_version = 4;
 

src/compiler/objective_c_plugin.cc

@@ -71,14 +71,10 @@ class ObjectiveCGrpcGenerator : public grpc::protobuf::compiler::CodeGenerator {
   virtual ~ObjectiveCGrpcGenerator() {}
 
  public:
-  uint64_t GetSupportedFeatures() const override {
-    return FEATURE_PROTO3_OPTIONAL;
-  }
-
   virtual bool Generate(const grpc::protobuf::FileDescriptor* file,
                         const ::grpc::string& parameter,
                         grpc::protobuf::compiler::GeneratorContext* context,
-                        ::grpc::string* error) const override {
+                        ::grpc::string* error) const {
     if (file->service_count() == 0) {
       // No services.  Do nothing.
       return true;

src/compiler/php_plugin.cc

@@ -33,14 +33,10 @@ class PHPGrpcGenerator : public grpc::protobuf::compiler::CodeGenerator {
   PHPGrpcGenerator() {}
   ~PHPGrpcGenerator() {}
 
-  uint64_t GetSupportedFeatures() const override {
-    return FEATURE_PROTO3_OPTIONAL;
-  }
-
   bool Generate(const grpc::protobuf::FileDescriptor* file,
                 const grpc::string& parameter,
                 grpc::protobuf::compiler::GeneratorContext* context,
-                grpc::string* error) const override {
+                grpc::string* error) const {
     if (file->service_count() == 0) {
       return true;
     }

src/compiler/python_generator.cc

@@ -875,10 +875,6 @@ static bool ParseParameters(const grpc::string& parameter,
   return true;
 }
 
-uint64_t PythonGrpcGenerator::GetSupportedFeatures() const {
-  return FEATURE_PROTO3_OPTIONAL;
-}
-
 bool PythonGrpcGenerator::Generate(const FileDescriptor* file,
                                    const grpc::string& parameter,
                                    GeneratorContext* context,

src/compiler/python_generator.h

@@ -44,12 +44,10 @@ class PythonGrpcGenerator : public grpc::protobuf::compiler::CodeGenerator {
   PythonGrpcGenerator(const GeneratorConfiguration& config);
   ~PythonGrpcGenerator();
 
-  uint64_t GetSupportedFeatures() const override;
-
   bool Generate(const grpc::protobuf::FileDescriptor* file,
                 const grpc::string& parameter,
                 grpc::protobuf::compiler::GeneratorContext* context,
-                grpc::string* error) const override;
+                grpc::string* error) const;
 
  private:
   GeneratorConfiguration config_;

src/compiler/ruby_plugin.cc

@@ -29,14 +29,10 @@ class RubyGrpcGenerator : public grpc::protobuf::compiler::CodeGenerator {
   RubyGrpcGenerator() {}
   ~RubyGrpcGenerator() {}
 
-  uint64_t GetSupportedFeatures() const override {
-    return FEATURE_PROTO3_OPTIONAL;
-  }
-
   bool Generate(const grpc::protobuf::FileDescriptor* file,
                 const grpc::string& /*parameter*/,
                 grpc::protobuf::compiler::GeneratorContext* context,
-                grpc::string* /*error*/) const override {
+                grpc::string* /*error*/) const {
     grpc::string code = grpc_ruby_generator::GetServices(file);
     if (code.size() == 0) {
       return true;  // don't generate a file if there are no services

src/core/ext/upb-generated/google/protobuf/descriptor.upb.c

@@ -130,24 +130,23 @@ static const upb_msglayout *const google_protobuf_FieldDescriptorProto_submsgs[1
   &google_protobuf_FieldOptions_msginit,
 };
 
-static const upb_msglayout_field google_protobuf_FieldDescriptorProto__fields[11] = {
-  {1, UPB_SIZE(36, 40), 6, 0, 9, 1},
-  {2, UPB_SIZE(44, 56), 7, 0, 9, 1},
+static const upb_msglayout_field google_protobuf_FieldDescriptorProto__fields[10] = {
+  {1, UPB_SIZE(32, 32), 5, 0, 9, 1},
+  {2, UPB_SIZE(40, 48), 6, 0, 9, 1},
   {3, UPB_SIZE(24, 24), 3, 0, 5, 1},
   {4, UPB_SIZE(8, 8), 1, 0, 14, 1},
   {5, UPB_SIZE(16, 16), 2, 0, 14, 1},
-  {6, UPB_SIZE(52, 72), 8, 0, 9, 1},
-  {7, UPB_SIZE(60, 88), 9, 0, 9, 1},
-  {8, UPB_SIZE(76, 120), 11, 0, 11, 1},
+  {6, UPB_SIZE(48, 64), 7, 0, 9, 1},
+  {7, UPB_SIZE(56, 80), 8, 0, 9, 1},
+  {8, UPB_SIZE(72, 112), 10, 0, 11, 1},
   {9, UPB_SIZE(28, 28), 4, 0, 5, 1},
-  {10, UPB_SIZE(68, 104), 10, 0, 9, 1},
-  {17, UPB_SIZE(32, 32), 5, 0, 8, 1},
+  {10, UPB_SIZE(64, 96), 9, 0, 9, 1},
 };
 
 const upb_msglayout google_protobuf_FieldDescriptorProto_msginit = {
   &google_protobuf_FieldDescriptorProto_submsgs[0],
   &google_protobuf_FieldDescriptorProto__fields[0],
-  UPB_SIZE(80, 128), 11, false,
+  UPB_SIZE(80, 128), 10, false,
 };
 
 static const upb_msglayout *const google_protobuf_OneofDescriptorProto_submsgs[1] = {

src/core/ext/upb-generated/google/protobuf/descriptor.upb.h

@@ -598,36 +598,34 @@ UPB_INLINE char *google_protobuf_FieldDescriptorProto_serialize(const google_pro
   return upb_encode(msg, &google_protobuf_FieldDescriptorProto_msginit, arena, len);
 }
 
-UPB_INLINE bool google_protobuf_FieldDescriptorProto_has_name(const google_protobuf_FieldDescriptorProto *msg) { return _upb_has_field(msg, 6); }
-UPB_INLINE upb_strview google_protobuf_FieldDescriptorProto_name(const google_protobuf_FieldDescriptorProto *msg) { return UPB_FIELD_AT(msg, upb_strview, UPB_SIZE(36, 40)); }
-UPB_INLINE bool google_protobuf_FieldDescriptorProto_has_extendee(const google_protobuf_FieldDescriptorProto *msg) { return _upb_has_field(msg, 7); }
-UPB_INLINE upb_strview google_protobuf_FieldDescriptorProto_extendee(const google_protobuf_FieldDescriptorProto *msg) { return UPB_FIELD_AT(msg, upb_strview, UPB_SIZE(44, 56)); }
+UPB_INLINE bool google_protobuf_FieldDescriptorProto_has_name(const google_protobuf_FieldDescriptorProto *msg) { return _upb_has_field(msg, 5); }
+UPB_INLINE upb_strview google_protobuf_FieldDescriptorProto_name(const google_protobuf_FieldDescriptorProto *msg) { return UPB_FIELD_AT(msg, upb_strview, UPB_SIZE(32, 32)); }
+UPB_INLINE bool google_protobuf_FieldDescriptorProto_has_extendee(const google_protobuf_FieldDescriptorProto *msg) { return _upb_has_field(msg, 6); }
+UPB_INLINE upb_strview google_protobuf_FieldDescriptorProto_extendee(const google_protobuf_FieldDescriptorProto *msg) { return UPB_FIELD_AT(msg, upb_strview, UPB_SIZE(40, 48)); }
 UPB_INLINE bool google_protobuf_FieldDescriptorProto_has_number(const google_protobuf_FieldDescriptorProto *msg) { return _upb_has_field(msg, 3); }
 UPB_INLINE int32_t google_protobuf_FieldDescriptorProto_number(const google_protobuf_FieldDescriptorProto *msg) { return UPB_FIELD_AT(msg, int32_t, UPB_SIZE(24, 24)); }
 UPB_INLINE bool google_protobuf_FieldDescriptorProto_has_label(const google_protobuf_FieldDescriptorProto *msg) { return _upb_has_field(msg, 1); }
 UPB_INLINE int32_t google_protobuf_FieldDescriptorProto_label(const google_protobuf_FieldDescriptorProto *msg) { return UPB_FIELD_AT(msg, int32_t, UPB_SIZE(8, 8)); }
 UPB_INLINE bool google_protobuf_FieldDescriptorProto_has_type(const google_protobuf_FieldDescriptorProto *msg) { return _upb_has_field(msg, 2); }
 UPB_INLINE int32_t google_protobuf_FieldDescriptorProto_type(const google_protobuf_FieldDescriptorProto *msg) { return UPB_FIELD_AT(msg, int32_t, UPB_SIZE(16, 16)); }
-UPB_INLINE bool google_protobuf_FieldDescriptorProto_has_type_name(const google_protobuf_FieldDescriptorProto *msg) { return _upb_has_field(msg, 8); }
-UPB_INLINE upb_strview google_protobuf_FieldDescriptorProto_type_name(const google_protobuf_FieldDescriptorProto *msg) { return UPB_FIELD_AT(msg, upb_strview, UPB_SIZE(52, 72)); }
-UPB_INLINE bool google_protobuf_FieldDescriptorProto_has_default_value(const google_protobuf_FieldDescriptorProto *msg) { return _upb_has_field(msg, 9); }
-UPB_INLINE upb_strview google_protobuf_FieldDescriptorProto_default_value(const google_protobuf_FieldDescriptorProto *msg) { return UPB_FIELD_AT(msg, upb_strview, UPB_SIZE(60, 88)); }
-UPB_INLINE bool google_protobuf_FieldDescriptorProto_has_options(const google_protobuf_FieldDescriptorProto *msg) { return _upb_has_field(msg, 11); }
-UPB_INLINE const google_protobuf_FieldOptions* google_protobuf_FieldDescriptorProto_options(const google_protobuf_FieldDescriptorProto *msg) { return UPB_FIELD_AT(msg, const google_protobuf_FieldOptions*, UPB_SIZE(76, 120)); }
+UPB_INLINE bool google_protobuf_FieldDescriptorProto_has_type_name(const google_protobuf_FieldDescriptorProto *msg) { return _upb_has_field(msg, 7); }
+UPB_INLINE upb_strview google_protobuf_FieldDescriptorProto_type_name(const google_protobuf_FieldDescriptorProto *msg) { return UPB_FIELD_AT(msg, upb_strview, UPB_SIZE(48, 64)); }
+UPB_INLINE bool google_protobuf_FieldDescriptorProto_has_default_value(const google_protobuf_FieldDescriptorProto *msg) { return _upb_has_field(msg, 8); }
+UPB_INLINE upb_strview google_protobuf_FieldDescriptorProto_default_value(const google_protobuf_FieldDescriptorProto *msg) { return UPB_FIELD_AT(msg, upb_strview, UPB_SIZE(56, 80)); }
+UPB_INLINE bool google_protobuf_FieldDescriptorProto_has_options(const google_protobuf_FieldDescriptorProto *msg) { return _upb_has_field(msg, 10); }
+UPB_INLINE const google_protobuf_FieldOptions* google_protobuf_FieldDescriptorProto_options(const google_protobuf_FieldDescriptorProto *msg) { return UPB_FIELD_AT(msg, const google_protobuf_FieldOptions*, UPB_SIZE(72, 112)); }
 UPB_INLINE bool google_protobuf_FieldDescriptorProto_has_oneof_index(const google_protobuf_FieldDescriptorProto *msg) { return _upb_has_field(msg, 4); }
 UPB_INLINE int32_t google_protobuf_FieldDescriptorProto_oneof_index(const google_protobuf_FieldDescriptorProto *msg) { return UPB_FIELD_AT(msg, int32_t, UPB_SIZE(28, 28)); }
-UPB_INLINE bool google_protobuf_FieldDescriptorProto_has_json_name(const google_protobuf_FieldDescriptorProto *msg) { return _upb_has_field(msg, 10); }
-UPB_INLINE upb_strview google_protobuf_FieldDescriptorProto_json_name(const google_protobuf_FieldDescriptorProto *msg) { return UPB_FIELD_AT(msg, upb_strview, UPB_SIZE(68, 104)); }
-UPB_INLINE bool google_protobuf_FieldDescriptorProto_has_proto3_optional(const google_protobuf_FieldDescriptorProto *msg) { return _upb_has_field(msg, 5); }
-UPB_INLINE bool google_protobuf_FieldDescriptorProto_proto3_optional(const google_protobuf_FieldDescriptorProto *msg) { return UPB_FIELD_AT(msg, bool, UPB_SIZE(32, 32)); }
+UPB_INLINE bool google_protobuf_FieldDescriptorProto_has_json_name(const google_protobuf_FieldDescriptorProto *msg) { return _upb_has_field(msg, 9); }
+UPB_INLINE upb_strview google_protobuf_FieldDescriptorProto_json_name(const google_protobuf_FieldDescriptorProto *msg) { return UPB_FIELD_AT(msg, upb_strview, UPB_SIZE(64, 96)); }
 
 UPB_INLINE void google_protobuf_FieldDescriptorProto_set_name(google_protobuf_FieldDescriptorProto *msg, upb_strview value) {
-  _upb_sethas(msg, 6);
-  UPB_FIELD_AT(msg, upb_strview, UPB_SIZE(36, 40)) = value;
+  _upb_sethas(msg, 5);
+  UPB_FIELD_AT(msg, upb_strview, UPB_SIZE(32, 32)) = value;
 }
 UPB_INLINE void google_protobuf_FieldDescriptorProto_set_extendee(google_protobuf_FieldDescriptorProto *msg, upb_strview value) {
-  _upb_sethas(msg, 7);
-  UPB_FIELD_AT(msg, upb_strview, UPB_SIZE(44, 56)) = value;
+  _upb_sethas(msg, 6);
+  UPB_FIELD_AT(msg, upb_strview, UPB_SIZE(40, 48)) = value;
 }
 UPB_INLINE void google_protobuf_FieldDescriptorProto_set_number(google_protobuf_FieldDescriptorProto *msg, int32_t value) {
   _upb_sethas(msg, 3);
@@ -642,16 +640,16 @@ UPB_INLINE void google_protobuf_FieldDescriptorProto_set_type(google_protobuf_Fi
   UPB_FIELD_AT(msg, int32_t, UPB_SIZE(16, 16)) = value;
 }
 UPB_INLINE void google_protobuf_FieldDescriptorProto_set_type_name(google_protobuf_FieldDescriptorProto *msg, upb_strview value) {
-  _upb_sethas(msg, 8);
-  UPB_FIELD_AT(msg, upb_strview, UPB_SIZE(52, 72)) = value;
+  _upb_sethas(msg, 7);
+  UPB_FIELD_AT(msg, upb_strview, UPB_SIZE(48, 64)) = value;
 }
 UPB_INLINE void google_protobuf_FieldDescriptorProto_set_default_value(google_protobuf_FieldDescriptorProto *msg, upb_strview value) {
-  _upb_sethas(msg, 9);
-  UPB_FIELD_AT(msg, upb_strview, UPB_SIZE(60, 88)) = value;
+  _upb_sethas(msg, 8);
+  UPB_FIELD_AT(msg, upb_strview, UPB_SIZE(56, 80)) = value;
 }
 UPB_INLINE void google_protobuf_FieldDescriptorProto_set_options(google_protobuf_FieldDescriptorProto *msg, google_protobuf_FieldOptions* value) {
-  _upb_sethas(msg, 11);
-  UPB_FIELD_AT(msg, google_protobuf_FieldOptions*, UPB_SIZE(76, 120)) = value;
+  _upb_sethas(msg, 10);
+  UPB_FIELD_AT(msg, google_protobuf_FieldOptions*, UPB_SIZE(72, 112)) = value;
 }
 UPB_INLINE struct google_protobuf_FieldOptions* google_protobuf_FieldDescriptorProto_mutable_options(google_protobuf_FieldDescriptorProto *msg, upb_arena *arena) {
   struct google_protobuf_FieldOptions* sub = (struct google_protobuf_FieldOptions*)google_protobuf_FieldDescriptorProto_options(msg);
@@ -667,12 +665,8 @@ UPB_INLINE void google_protobuf_FieldDescriptorProto_set_oneof_index(google_prot
   UPB_FIELD_AT(msg, int32_t, UPB_SIZE(28, 28)) = value;
 }
 UPB_INLINE void google_protobuf_FieldDescriptorProto_set_json_name(google_protobuf_FieldDescriptorProto *msg, upb_strview value) {
-  _upb_sethas(msg, 10);
-  UPB_FIELD_AT(msg, upb_strview, UPB_SIZE(68, 104)) = value;
-}
-UPB_INLINE void google_protobuf_FieldDescriptorProto_set_proto3_optional(google_protobuf_FieldDescriptorProto *msg, bool value) {
-  _upb_sethas(msg, 5);
-  UPB_FIELD_AT(msg, bool, UPB_SIZE(32, 32)) = value;
+  _upb_sethas(msg, 9);
+  UPB_FIELD_AT(msg, upb_strview, UPB_SIZE(64, 96)) = value;
 }
 
 /* google.protobuf.OneofDescriptorProto */

src/cpp/Protobuf-C++.podspec

@@ -1,6 +1,6 @@
 Pod::Spec.new do |s|
   s.name     = 'Protobuf-C++'
-  s.version  = '3.12.2'
+  s.version  = '3.11.4'
   s.summary  = 'Protocol Buffers v3 runtime library for C++.'
   s.homepage = 'https://github.com/google/protobuf'
   s.license  = '3-Clause BSD License'

src/csharp/build/dependencies.props

@@ -2,6 +2,6 @@
 <Project>
   <PropertyGroup>
     <GrpcCsharpVersion>2.30.0-dev</GrpcCsharpVersion>
-    <GoogleProtobufVersion>3.12.2</GoogleProtobufVersion>
+    <GoogleProtobufVersion>3.11.4</GoogleProtobufVersion>
   </PropertyGroup>
 </Project>

src/objective-c/!ProtoCompiler-gRPCCppPlugin.podspec

@@ -100,7 +100,7 @@ Pod::Spec.new do |s|
   s.preserve_paths = plugin
 
   # Restrict the protoc version to the one supported by this plugin.
-  s.dependency '!ProtoCompiler', '3.12.2'
+  s.dependency '!ProtoCompiler', '3.11.4'
   # For the Protobuf dependency not to complain:
   s.ios.deployment_target = '7.0'
   s.osx.deployment_target = '10.9'

src/objective-c/!ProtoCompiler-gRPCPlugin.podspec

@@ -102,7 +102,7 @@ Pod::Spec.new do |s|
   s.preserve_paths = plugin
 
   # Restrict the protoc version to the one supported by this plugin.
-  s.dependency '!ProtoCompiler', '3.12.2'
+  s.dependency '!ProtoCompiler', '3.11.4'
   # For the Protobuf dependency not to complain:
   s.ios.deployment_target = '7.0'
   s.osx.deployment_target = '10.9'

src/objective-c/!ProtoCompiler.podspec

@@ -36,7 +36,7 @@ Pod::Spec.new do |s|
   # exclamation mark ensures that other "regular" pods will be able to find it as it'll be installed
   # before them.
   s.name     = '!ProtoCompiler'
-  v = '3.12.2'
+  v = '3.11.4'
   s.version  = v
   s.summary  = 'The Protobuf Compiler (protoc) generates Objective-C files from .proto files'
   s.description = <<-DESC

templates/grpc.gemspec.template

@@ -34,7 +34,7 @@
     s.require_paths = %w( src/ruby/lib src/ruby/bin src/ruby/pb )
     s.platform      = Gem::Platform::RUBY
 
-    s.add_dependency 'google-protobuf', '~> 3.12'
+    s.add_dependency 'google-protobuf', '~> 3.11'
     s.add_dependency 'googleapis-common-protos-types', '~> 1.0'
 
     s.add_development_dependency 'bundler',            '>= 1.9'

templates/src/csharp/build/dependencies.props.template

@@ -4,6 +4,6 @@
   <Project>
     <PropertyGroup>
       <GrpcCsharpVersion>${settings.csharp_version}</GrpcCsharpVersion>
-      <GoogleProtobufVersion>3.12.2</GoogleProtobufVersion>
+      <GoogleProtobufVersion>3.11.4</GoogleProtobufVersion>
     </PropertyGroup>
   </Project>

templates/src/objective-c/!ProtoCompiler-gRPCCppPlugin.podspec.template

@@ -102,7 +102,7 @@
     s.preserve_paths = plugin
 
     # Restrict the protoc version to the one supported by this plugin.
-    s.dependency '!ProtoCompiler', '3.12.2'
+    s.dependency '!ProtoCompiler', '3.11.4'
     # For the Protobuf dependency not to complain:
     s.ios.deployment_target = '7.0'
     s.osx.deployment_target = '10.9'

templates/src/objective-c/!ProtoCompiler-gRPCPlugin.podspec.template

@@ -104,7 +104,7 @@
     s.preserve_paths = plugin
 
     # Restrict the protoc version to the one supported by this plugin.
-    s.dependency '!ProtoCompiler', '3.12.2'
+    s.dependency '!ProtoCompiler', '3.11.4'
     # For the Protobuf dependency not to complain:
     s.ios.deployment_target = '7.0'
     s.osx.deployment_target = '10.9'

templates/tools/dockerfile/test/cxx_alpine_x64/Dockerfile.template

@@ -14,7 +14,7 @@
   # See the License for the specific language governing permissions and
   # limitations under the License.
 
-  FROM alpine:3.9
+  FROM alpine:3.5
 
   # Install Git and basic packages.
   RUN apk update && apk add ${'\\'}