C++ bindings: separate out serialization source set, have "mojom" targets optionally use serializat…

mojo/public/cpp/bindings/BUILD.gn

Index: mojo/public/cpp/bindings/BUILD.gn
diff --git a/mojo/public/cpp/bindings/BUILD.gn b/mojo/public/cpp/bindings/BUILD.gn
index 27f9cf75079f49d62d51c6376c5bfe4723ab01d7..567a0a0b8565f3a604e297455597eeee191122da 100644
--- a/mojo/public/cpp/bindings/BUILD.gn
+++ b/mojo/public/cpp/bindings/BUILD.gn
@@ -4,13 +4,10 @@
 
 import("../../mojo_sdk.gni")
 
-mojo_sdk_source_set("bindings") {
+mojo_sdk_source_set("serialization_base") {

[viettrungluu, 2015/10/19 19:37:54]

This target deserves an explanatory comment.

[vardhan, 2015/10/19 23:18:30]

Done.

   sources = [
     "array.h",
-    "binding.h",
-    "interface_ptr.h",
-    "interface_ptr_info.h",
-    "interface_request.h",
+    "interface_request.h",  # for array_serialization.h

[viettrungluu, 2015/10/19 19:37:54]

Is it possible to avoid this (maybe by splitting up array_serialization.h)?

[vardhan, 2015/10/19 23:18:31]

The simpliest way is that I could forward declare MakeRequest() (the only reason
we need interface_request.h), LMK what you think?  (this would require a user to
include interface_request.h if they want to deserialize an array<> of interface
requests.  Seems fair

But otherwise, I think it would be weird to split up array_serialization.h for
individual types?  What I'm thinking of is we would have
"ArraySerializer<InterfaceRequest<I>, MessagePipeHandle, false>"  defined in a
separate header (array_serialization_interface_request.h or something) that
needs to be included in places you specifically want to deserialize an array of
interface requests.  Seems cumbersome to use?

     "lib/array_internal.cc",
     "lib/array_internal.h",
     "lib/array_serialization.h",
@@ -20,33 +17,16 @@ mojo_sdk_source_set("bindings") {
     "lib/bounds_checker.cc",
     "lib/bounds_checker.h",
     "lib/buffer.h",
-    "lib/connector.cc",
-    "lib/connector.h",
-    "lib/control_message_handler.cc",
-    "lib/control_message_handler.h",
-    "lib/control_message_proxy.cc",
-    "lib/control_message_proxy.h",
-    "lib/filter_chain.cc",
-    "lib/filter_chain.h",
     "lib/fixed_buffer.cc",
     "lib/fixed_buffer.h",
-    "lib/interface_ptr_internal.h",
     "lib/iterator_util.h",
     "lib/map_data_internal.h",
     "lib/map_internal.h",
     "lib/map_serialization.h",
-    "lib/message.cc",
-    "lib/message_builder.cc",
-    "lib/message_builder.h",
-    "lib/message_filter.cc",
-    "lib/message_header_validator.cc",
-    "lib/message_header_validator.h",
-    "lib/message_internal.h",
-    "lib/no_interface.cc",
-    "lib/router.cc",
-    "lib/router.h",
+    "lib/message_internal.h",  # for message.h?
     "lib/string_serialization.cc",
     "lib/string_serialization.h",
+    "lib/template_util.h",
     "lib/union_accessor.h",
     "lib/validate_params.h",
     "lib/validation_errors.cc",
@@ -54,26 +34,66 @@ mojo_sdk_source_set("bindings") {
     "lib/validation_util.cc",
     "lib/validation_util.h",
     "map.h",
-    "message.h",
-    "message_filter.h",
-    "no_interface.h",
+    "message.h",  # for validation_util.h
     "string.h",
-    "strong_binding.h",
     "struct_ptr.h",
     "type_converter.h",
   ]
 
-  deps = [
+  public_deps = [
     ":callback",
   ]
 
-  mojo_sdk_deps = [
+  mojo_sdk_public_deps = [
     "mojo/public/cpp/environment",
     "mojo/public/cpp/system",
-    "mojo/public/interfaces/bindings:bindings_cpp_sources",
   ]
 }
 
+mojo_sdk_source_set("serialization") {

[viettrungluu, 2015/10/19 19:37:54]

So does this one.

[vardhan, 2015/10/19 23:18:31]

Done.

+  public_deps = [
+    ":serialization_base",
+  ]
+
+  mojo_sdk_deps = [ "mojo/public/cpp/environment:logging_only" ]

[viettrungluu, 2015/10/19 19:37:54]

Though it's probably better to leave it up to the user of the target to decide
what implementation of environment to use, obviating the need for two targets.

E.g., you may end up with a library, which only serializes, and so depends on
:serialization, which gets linked into something that uses the full environment.

(You can explain the possible need for the logging_only dependency in the
comment describing the target.)

[vardhan, 2015/10/19 23:18:30]

Hm.. If I do this, then a plain-old-executable can't be constructed with just
the "executable()" gn template, since that template doesn't provide us with a
mojo_sdk_deps arg..  We'd have to provide another template for that?

[vardhan, 2015/10/20 18:45:57]

Nevermind, I misunderstood how mojo_sdk_* is used, I made :serialization not
include an environment impl

+}
+
+mojo_sdk_source_set("bindings") {
+  sources = [
+    "binding.h",
+    "interface_ptr.h",
+    "interface_ptr_info.h",
+    "interface_request.h",
+    "lib/connector.cc",
+    "lib/connector.h",
+    "lib/control_message_handler.cc",
+    "lib/control_message_handler.h",
+    "lib/control_message_proxy.cc",
+    "lib/control_message_proxy.h",
+    "lib/filter_chain.cc",
+    "lib/filter_chain.h",
+    "lib/interface_ptr_internal.h",
+    "lib/message.cc",
+    "lib/message_builder.cc",
+    "lib/message_builder.h",
+    "lib/message_filter.cc",
+    "lib/message_header_validator.cc",
+    "lib/message_header_validator.h",
+    "lib/no_interface.cc",
+    "lib/router.cc",
+    "lib/router.h",
+    "message_filter.h",
+    "no_interface.h",
+    "strong_binding.h",
+  ]
+
+  public_deps = [
+    ":serialization_base",
+  ]
+
+  mojo_sdk_deps = [ "mojo/public/interfaces/bindings:bindings_cpp_sources" ]
+}
+
 mojo_sdk_source_set("callback") {
   sources = [
     "callback.h",