Adds support for per message compression

src/ruby/ext/grpc/rb_call.c

@@ -82,6 +82,10 @@ static ID id_metadata;
  * received by the call and subsequently saved on it. */
 static ID id_status;
 
+/* id_write_flag is name of the attribute used to access the write_flag
+ * saved on the call. */
+static ID id_write_flag;
+
 /* sym_* are the symbol for attributes of grpc_rb_sBatchResult. */
 static VALUE sym_send_message;
 static VALUE sym_send_metadata;
@@ -240,6 +244,30 @@ static VALUE grpc_rb_call_set_metadata(VALUE self, VALUE metadata) {
   return rb_ivar_set(self, id_metadata, metadata);
 }
 
+/*
+  call-seq:
+  write_flag = call.write_flag
+
+  Gets the write_flag value saved the call.  */
+static VALUE grpc_rb_call_get_write_flag(VALUE self) {
+  return rb_ivar_get(self, id_write_flag);
+}
+
+/*
+  call-seq:
+  call.write_flag = write_flag
+
+  Saves the write_flag on the call.  */
+static VALUE grpc_rb_call_set_write_flag(VALUE self, VALUE write_flag) {
+  if (!NIL_P(write_flag) && TYPE(write_flag) != T_FIXNUM) {
+    rb_raise(rb_eTypeError, "bad write_flag: got:<%s> want: <Fixnum>",
+             rb_obj_classname(write_flag));
+    return Qnil;
+  }
+
+  return rb_ivar_set(self, id_write_flag, write_flag);
+}
+
 /* grpc_rb_md_ary_fill_hash_cb is the hash iteration callback used
    to fill grpc_metadata_array.
 
@@ -437,17 +465,19 @@ typedef struct run_batch_stack {
   grpc_status_code recv_status;
   char *recv_status_details;
   size_t recv_status_details_capacity;
+  uint write_flag;
 } run_batch_stack;
 
 /* grpc_run_batch_stack_init ensures the run_batch_stack is properly
  * initialized */
-static void grpc_run_batch_stack_init(run_batch_stack *st) {
+static void grpc_run_batch_stack_init(run_batch_stack *st, uint write_flag) {
   MEMZERO(st, run_batch_stack, 1);
   grpc_metadata_array_init(&st->send_metadata);
   grpc_metadata_array_init(&st->send_trailing_metadata);
   grpc_metadata_array_init(&st->recv_metadata);
   grpc_metadata_array_init(&st->recv_trailing_metadata);
   st->op_num = 0;
+  st->write_flag = write_flag;
 }
 
 /* grpc_run_batch_stack_cleanup ensures the run_batch_stack is properly
@@ -477,6 +507,7 @@ static void grpc_run_batch_stack_fill_ops(run_batch_stack *st, VALUE ops_hash) {
   for (i = 0; i < (size_t)RARRAY_LEN(ops_ary); i++) {
     this_op = rb_ary_entry(ops_ary, i);
     this_value = rb_hash_aref(ops_hash, this_op);
+    st->ops[st->op_num].flags = 0;
     switch (NUM2INT(this_op)) {
       case GRPC_OP_SEND_INITIAL_METADATA:
         /* N.B. later there is no need to explicitly delete the metadata keys
@@ -490,6 +521,7 @@ static void grpc_run_batch_stack_fill_ops(run_batch_stack *st, VALUE ops_hash) {
       case GRPC_OP_SEND_MESSAGE:
         st->ops[st->op_num].data.send_message = grpc_rb_s_to_byte_buffer(
             RSTRING_PTR(this_value), RSTRING_LEN(this_value));
+        st->ops[st->op_num].flags = st->write_flag;
         break;
       case GRPC_OP_SEND_CLOSE_FROM_CLIENT:
         break;
@@ -525,7 +557,6 @@ static void grpc_run_batch_stack_fill_ops(run_batch_stack *st, VALUE ops_hash) {
                  NUM2INT(this_op));
     };
     st->ops[st->op_num].op = (grpc_op_type)NUM2INT(this_op);
-    st->ops[st->op_num].flags = 0;
     st->ops[st->op_num].reserved = NULL;
     st->op_num++;
   }
@@ -604,6 +635,8 @@ static VALUE grpc_rb_call_run_batch(VALUE self, VALUE cqueue, VALUE tag,
   grpc_event ev;
   grpc_call_error err;
   VALUE result = Qnil;
+  VALUE rb_write_flag = rb_ivar_get(self, id_write_flag);
+  uint write_flag = 0;
   TypedData_Get_Struct(self, grpc_call, &grpc_call_data_type, call);
 
   /* Validate the ops args, adding them to a ruby array */
@@ -611,7 +644,10 @@ static VALUE grpc_rb_call_run_batch(VALUE self, VALUE cqueue, VALUE tag,
     rb_raise(rb_eTypeError, "call#run_batch: ops hash should be a hash");
     return Qnil;
   }
-  grpc_run_batch_stack_init(&st);
+  if (rb_write_flag != Qnil) {
+    write_flag = NUM2UINT(rb_write_flag);
+  }
+  grpc_run_batch_stack_init(&st, write_flag);
   grpc_run_batch_stack_fill_ops(&st, ops_hash);
 
   /* call grpc_call_start_batch, then wait for it to complete using
@@ -638,6 +674,16 @@ static VALUE grpc_rb_call_run_batch(VALUE self, VALUE cqueue, VALUE tag,
   return result;
 }
 
+static void Init_grpc_write_flags() {
+  /* Constants representing the write flags in grpc.h */
+  VALUE grpc_rb_mWriteFlags =
+      rb_define_module_under(grpc_rb_mGrpcCore, "WriteFlags");
+  rb_define_const(grpc_rb_mWriteFlags, "BUFFER_HINT",
+                  UINT2NUM(GRPC_WRITE_BUFFER_HINT));
+  rb_define_const(grpc_rb_mWriteFlags, "NO_COMPRESS",
+                  UINT2NUM(GRPC_WRITE_NO_COMPRESS));
+}
+
 static void Init_grpc_error_codes() {
   /* Constants representing the error codes of grpc_call_error in grpc.h */
   VALUE grpc_rb_mRpcErrors =
@@ -735,10 +781,14 @@ void Init_grpc_call() {
   rb_define_method(grpc_rb_cCall, "status=", grpc_rb_call_set_status, 1);
   rb_define_method(grpc_rb_cCall, "metadata", grpc_rb_call_get_metadata, 0);
   rb_define_method(grpc_rb_cCall, "metadata=", grpc_rb_call_set_metadata, 1);
+  rb_define_method(grpc_rb_cCall, "write_flag", grpc_rb_call_get_write_flag, 0);
+  rb_define_method(grpc_rb_cCall, "write_flag=", grpc_rb_call_set_write_flag,
+                   1);
 
   /* Ids used to support call attributes */
   id_metadata = rb_intern("metadata");
   id_status = rb_intern("status");
+  id_write_flag = rb_intern("write_flag");
 
   /* Ids used by the c wrapping internals. */
   id_cq = rb_intern("__cq");
@@ -766,6 +816,7 @@ void Init_grpc_call() {
 
   Init_grpc_error_codes();
   Init_grpc_op_codes();
+  Init_grpc_write_flags();
 }
 
 /* Gets the call from the ruby object */

src/ruby/lib/grpc/generic/active_call.rb

@@ -59,7 +59,7 @@ module GRPC
     include Core::CallOps
     extend Forwardable
     attr_reader(:deadline)
-    def_delegators :@call, :cancel, :metadata
+    def_delegators :@call, :cancel, :metadata, :write_flag, :write_flag=
 
     # client_invoke begins a client invocation.
     #
@@ -484,6 +484,7 @@ module GRPC
     # Operation limits access to an ActiveCall's methods for use as
     # a Operation on the client.
     Operation = view_class(:cancel, :cancelled, :deadline, :execute,
-                           :metadata, :status, :start_call, :wait)
+                           :metadata, :status, :start_call, :wait, :write_flag,
+                           :write_flag=)
   end
 end

src/ruby/spec/call_spec.rb

@@ -31,6 +31,14 @@ require 'grpc'
 
 include GRPC::Core::StatusCodes
 
+describe GRPC::Core::WriteFlags do
+  it 'should define the known write flag values' do
+    m = GRPC::Core::WriteFlags
+    expect(m.const_get(:BUFFER_HINT)).to_not be_nil
+    expect(m.const_get(:NO_COMPRESS)).to_not be_nil
+  end
+end
+
 describe GRPC::Core::RpcErrors do
   before(:each) do
     @known_types = {

src/ruby/spec/generic/active_call_spec.rb

@@ -35,6 +35,7 @@ describe GRPC::ActiveCall do
   ActiveCall = GRPC::ActiveCall
   Call = GRPC::Core::Call
   CallOps = GRPC::Core::CallOps
+  WriteFlags = GRPC::Core::WriteFlags
 
   before(:each) do
     @pass_through = proc { |x| x }
@@ -129,6 +130,31 @@ describe GRPC::ActiveCall do
                                    @pass_through, deadline)
       expect(server_call.remote_read).to eq('marshalled:' + msg)
     end
+
+    TEST_WRITE_FLAGS = [WriteFlags::BUFFER_HINT, WriteFlags::NO_COMPRESS]
+    TEST_WRITE_FLAGS.each do |f|
+      it "successfully makes calls with write_flag set to #{f}" do
+        call = make_test_call
+        ActiveCall.client_invoke(call, @client_queue)
+        marshal = proc { |x| 'marshalled:' + x }
+        client_call = ActiveCall.new(call, @client_queue, marshal,
+                                     @pass_through, deadline)
+        msg = 'message is a string'
+        client_call.write_flag = f
+        client_call.remote_send(msg)
+
+        # confirm that the message was marshalled
+        recvd_rpc =  @server.request_call(@server_queue, @server_tag, deadline)
+        recvd_call = recvd_rpc.call
+        server_ops = {
+          CallOps::SEND_INITIAL_METADATA => nil
+        }
+        recvd_call.run_batch(@server_queue, @server_tag, deadline, server_ops)
+        server_call = ActiveCall.new(recvd_call, @server_queue, @pass_through,
+                                     @pass_through, deadline)
+        expect(server_call.remote_read).to eq('marshalled:' + msg)
+      end
+    end
   end
 
   describe '#client_invoke' do
@@ -261,7 +287,7 @@ describe GRPC::ActiveCall do
       client_call.writes_done(false)
       server_call = expect_server_to_receive(msg)
       e = client_call.each_remote_read
-      n = 3  # arbitrary value > 1
+      n = 3 # arbitrary value > 1
       n.times do
         server_call.remote_send(reply)
         expect(e.next).to eq(reply)