Add serde feature flag to prost-types

Adds "serde_deserialize", "serde_serialize" and "serde" flags to
prost-types. This will allow users to enable serde support to the
well known types.

closes #852

Author: allada

prost-types/Cargo.toml

@@ -16,11 +16,15 @@ doctest = false
 default = ["std"]
 std = ["prost/std"]
 arbitrary = ["dep:arbitrary"]
+serde = ["serde_serialize", "serde_deserialize"]
+serde_serialize = ["std", "dep:serde"]
+serde_deserialize = ["std", "dep:serde"]
 
 [dependencies]
 prost = { version = "0.13.5", path = "../prost", default-features = false, features = ["prost-derive"] }
 arbitrary = { version = "1.4", features = ["derive"], optional = true }
 chrono = { version = "0.4.34", default-features = false, optional = true }
+serde = { version = "1.0.218", default-features = false, optional = true, features = ["derive", "std"] }
 
 [dev-dependencies]
 proptest = "1"

prost-types/src/compiler.rs

@@ -1,6 +1,8 @@
 // This file is @generated by prost-build.
 /// The version number of protocol compiler.
 #[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
+#[cfg_attr(feature = "serde_serialize", derive(serde::Serialize))]
+#[cfg_attr(feature = "serde_deserialize", derive(serde::Deserialize))]
 #[derive(Clone, PartialEq, Eq, Hash, ::prost::Message)]
 pub struct Version {
     #[prost(int32, optional, tag = "1")]
@@ -16,6 +18,8 @@ pub struct Version {
 }
 /// An encoded CodeGeneratorRequest is written to the plugin's stdin.
 #[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
+#[cfg_attr(feature = "serde_serialize", derive(serde::Serialize))]
+#[cfg_attr(feature = "serde_deserialize", derive(serde::Deserialize))]
 #[derive(Clone, PartialEq, ::prost::Message)]
 pub struct CodeGeneratorRequest {
     /// The .proto files that were explicitly listed on the command-line.  The
@@ -48,6 +52,8 @@ pub struct CodeGeneratorRequest {
 }
 /// The plugin writes an encoded CodeGeneratorResponse to stdout.
 #[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
+#[cfg_attr(feature = "serde_serialize", derive(serde::Serialize))]
+#[cfg_attr(feature = "serde_deserialize", derive(serde::Deserialize))]
 #[derive(Clone, PartialEq, ::prost::Message)]
 pub struct CodeGeneratorResponse {
     /// Error message.  If non-empty, code generation failed.  The plugin process
@@ -71,6 +77,8 @@ pub struct CodeGeneratorResponse {
 pub mod code_generator_response {
     /// Represents a single generated file.
     #[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
+    #[cfg_attr(feature = "serde_serialize", derive(serde::Serialize))]
+    #[cfg_attr(feature = "serde_deserialize", derive(serde::Deserialize))]
     #[derive(Clone, PartialEq, ::prost::Message)]
     pub struct File {
         /// The file name, relative to the output directory.  The name must not
@@ -136,6 +144,8 @@ pub mod code_generator_response {
     }
     /// Sync with code_generator.h.
     #[cfg_attr(feature = "arbitrary", derive(arbitrary::Arbitrary))]
+    #[cfg_attr(feature = "serde_serialize", derive(serde::Serialize))]
+    #[cfg_attr(feature = "serde_deserialize", derive(serde::Deserialize))]
     #[derive(
         Clone,
         Copy,