Add prost-wkt-derive to derive MessageSerde

Cargo.toml

@@ -11,13 +11,15 @@ edition = "2021"
 rust-version = "1.70"
 
 [workspace]
-members = [ "wkt-build", "wkt-types", "example" ]
+members = ["wkt-types", "wkt-derive", "example"]
 
 [dependencies]
 prost = "0.13.1"
+prost-wkt-derive = { path = "wkt-derive" }
+erased-serde = "0.4"
 inventory = "0.3.0"
 serde = "1.0"
 serde_json = "1.0"
 serde_derive = "1.0"
 chrono = { version = "0.4.27", default-features = false, features = ["serde"] }
-typetag = "0.2"
+const_format = "0.2.32"

README.md

@@ -26,7 +26,6 @@ serde = { version = "1.0", features = ["derive"] }
 
 [build-dependencies]
 prost-build = "0.13"
-prost-wkt-build = "0.6"
 ```
 
 In your `build.rs`, make sure to add the following options:
@@ -290,7 +289,7 @@ Contributions are welcome!
 When upgrading Prost to the latest version, make sure the latest changes from `prost-types` are incorporated into `prost-wkt-types` to ensure full compatibility.
 
 Currently the `Name` traits have specifically not been implemented until this implementation in Prost has fully
-stabilized. 
+stabilized.
 
 ## MSRV ##
 

example/Cargo.toml

@@ -9,11 +9,13 @@ rust-version = "1.70"
 prost = "0.13.1"
 prost-wkt = { path = ".." }
 prost-wkt-types = { path = "../wkt-types" }
-serde = "1.0"
+serde = { version = "1.0", features = ["derive"] }
 serde_derive = "1.0"
 serde_json = "1.0"
-chrono = { version = "0.4.27", default-features = false, features = ["clock", "serde"] }
+chrono = { version = "0.4.27", default-features = false, features = [
+    "clock",
+    "serde",
+] }
 
 [build-dependencies]
 prost-build = "0.13.1"
-prost-wkt-build = { path = "../wkt-build" }

example/build.rs

@@ -1,32 +1,30 @@
-use prost_wkt_build::*;
 use std::{env, path::PathBuf};
 
 fn main() {
     let out = PathBuf::from(env::var("OUT_DIR").unwrap());
     let descriptor_file = out.join("descriptors.bin");
     let mut prost_build = prost_build::Config::new();
     prost_build
+        .enable_type_names()
+        .type_name_domain(&[".my.requests", ".my.messages"], "type.googleapis.com")
         .type_attribute(
             ".my.requests",
-            "#[derive(serde::Serialize, serde::Deserialize)] #[serde(default, rename_all=\"camelCase\")]",
+            "#[derive(serde::Serialize, serde::Deserialize, ::prost_wkt::MessageSerde)] #[serde(default, rename_all=\"camelCase\")]",
         )
         .type_attribute(
             ".my.messages.Foo",
             "#[derive(serde::Serialize, serde::Deserialize)] #[serde(default, rename_all=\"camelCase\")]",
         )
+        .message_attribute(".my.messages.Foo", "#[derive(::prost_wkt::MessageSerde)]")
         .type_attribute(
             ".my.messages.Content",
             "#[derive(serde::Serialize, serde::Deserialize)] #[serde(rename_all=\"camelCase\")]",
         )
+        .message_attribute(".my.messages.Content", "#[derive(::prost_wkt::MessageSerde)]")
         .extern_path(".google.protobuf.Any", "::prost_wkt_types::Any")
         .extern_path(".google.protobuf.Timestamp", "::prost_wkt_types::Timestamp")
         .extern_path(".google.protobuf.Value", "::prost_wkt_types::Value")
         .file_descriptor_set_path(&descriptor_file)
         .compile_protos(&["proto/messages.proto", "proto/requests.proto"], &["proto/"])
         .unwrap();
-
-    let descriptor_bytes = std::fs::read(descriptor_file).unwrap();
-    let descriptor = FileDescriptorSet::decode(&descriptor_bytes[..]).unwrap();
-
-    prost_wkt_build::add_serde(out, descriptor);
 }

example/src/main.rs

@@ -6,8 +6,9 @@ include!(concat!(env!("OUT_DIR"), "/my.messages.rs"));
 include!(concat!(env!("OUT_DIR"), "/my.requests.rs"));
 
 fn main() -> Result<(), AnyError> {
-
-    let content: Content = Content { body: Some(content::Body::SomeBool(true)) };
+    let content: Content = Content {
+        body: Some(content::Body::SomeBool(true)),
+    };
 
     let foo_msg: Foo = Foo {
         data: "Hello World".to_string(),

src/lib.rs

@@ -1,20 +1,17 @@
 pub use inventory;
 
-pub use typetag;
+pub use const_format;
+pub use erased_serde;
+pub use prost_wkt_derive::MessageSerde;
 
 /// Trait to support serialization and deserialization of `prost` messages.
-#[typetag::serde(tag = "@type")]
-pub trait MessageSerde: prost::Message + std::any::Any {
-    /// message name as in proto file
-    fn message_name(&self) -> &'static str;
-    /// package name as in proto file
-    fn package_name(&self) -> &'static str;
+pub trait MessageSerde: prost::Message + std::any::Any + erased_serde::Serialize {
     /// the message proto type url e.g. type.googleapis.com/my.package.MyMessage
-    fn type_url(&self) -> &'static str;
-    /// Creates a new instance of this message using the protobuf encoded data
-    fn new_instance(&self, data: Vec<u8>) -> Result<Box<dyn MessageSerde>, prost::DecodeError>;
+    fn type_url(&self) -> String;
     /// Returns the encoded protobuf message as bytes
     fn try_encoded(&self) -> Result<Vec<u8>, prost::EncodeError>;
+    /// Returns an erased serialize dynamic reference
+    fn as_erased_serialize(&self) -> &dyn erased_serde::Serialize;
 }
 
 /// The implementation here is a direct copy of the `impl dyn` of [`std::any::Any`]!
@@ -85,11 +82,40 @@ impl dyn MessageSerde {
     }
 }
 
+type MessageSerdeTypeUrlFn = fn() -> String;
 type MessageSerdeDecoderFn = fn(&[u8]) -> Result<Box<dyn MessageSerde>, ::prost::DecodeError>;
+type MessageSerdeDeserializerFn =
+    fn(&mut dyn erased_serde::Deserializer) -> Result<Box<dyn MessageSerde>, erased_serde::Error>;
 
 pub struct MessageSerdeDecoderEntry {
-    pub type_url: &'static str,
+    pub type_url: MessageSerdeTypeUrlFn,
     pub decoder: MessageSerdeDecoderFn,
+    pub deserializer: MessageSerdeDeserializerFn,
+}
+
+impl MessageSerdeDecoderEntry {
+    pub const fn new<M>() -> Self
+    where
+        for<'a> M: MessageSerde + prost::Name + Default + serde::Deserialize<'a>,
+    {
+        Self {
+            type_url: <M as prost::Name>::type_url,
+            decoder: |buf| {
+                let msg: M = prost::Message::decode(buf)?;
+                Ok(Box::new(msg))
+            },
+            deserializer: deserialize_boxed::<M>,
+        }
+    }
+}
+
+fn deserialize_boxed<M>(
+    de: &mut dyn erased_serde::Deserializer,
+) -> Result<Box<dyn MessageSerde>, erased_serde::Error>
+where
+    for<'a> M: MessageSerde + serde::Deserialize<'a>,
+{
+    erased_serde::deserialize::<M>(de).map(|v| Box::new(v) as _)
 }
 
 inventory::collect!(MessageSerdeDecoderEntry);

wkt-derive/Cargo.toml

@@ -0,0 +1,18 @@
+[package]
+name = "prost-wkt-derive"
+version = "0.6.0"
+authors = ["fdeantoni <fdeantoni@gmail.com>"]
+license = "Apache-2.0"
+repository = "https://github.com/fdeantoni/prost-wkt"
+description = "Derive traits to assist with JSON serialization and deserialization of Well Known Types."
+readme = "../README.md"
+documentation = "https://docs.rs/prost-wkt-derive"
+edition = "2021"
+rust-version = "1.70"
+
+[lib]
+proc-macro = true
+
+[dependencies]
+quote = "1.0.37"
+syn = "2.0.76"

wkt-derive/src/lib.rs

@@ -0,0 +1,29 @@
+use proc_macro::TokenStream;
+use quote::quote;
+use syn::DeriveInput;
+
+#[proc_macro_derive(MessageSerde)]
+pub fn message_serde_derive(input: TokenStream) -> TokenStream {
+    let ast: DeriveInput = syn::parse(input).unwrap();
+    let name = &ast.ident;
+    let gen = quote! {
+        const _: () = {
+            impl ::prost_wkt::MessageSerde for #name {
+                fn type_url(&self) -> String { <#name as ::prost::Name>::type_url() }
+                fn try_encoded(&self) -> ::std::result::Result<::std::vec::Vec<u8>, ::prost::EncodeError> {
+                    let mut buf = ::std::vec::Vec::with_capacity(::prost::Message::encoded_len(self));
+                    ::prost::Message::encode(self, &mut buf)?;
+                    Ok(buf)
+                }
+                fn as_erased_serialize(&self) -> &dyn ::prost_wkt::erased_serde::Serialize {
+                    self
+                }
+            }
+
+            ::prost_wkt::inventory::submit!{
+                ::prost_wkt::MessageSerdeDecoderEntry::new::<#name>()
+            }
+        };
+    };
+    gen.into()
+}

wkt-types/Cargo.toml

@@ -27,13 +27,13 @@ prost = "0.13.1"
 serde = "1.0"
 serde_json = "1.0"
 serde_derive = "1.0"
+serde-value = "0.7"
 chrono = { version = "0.4.27", default-features = false, features = ["serde"] }
 
 [build-dependencies]
 prost = "0.13.1"
 prost-types = "0.13.1"
 prost-build = "0.13.1"
-prost-wkt-build = { version = "0.6.0", path = "../wkt-build" }
 regex = "1"
 protobuf-src = { version = "1.1.0", optional = true }
 protox = { version = "0.6.0", optional = true }

wkt-types/build.rs

@@ -2,9 +2,6 @@ use std::env;
 use std::fs::create_dir_all;
 use std::path::{Path, PathBuf};
 
-use prost::Message;
-use prost_types::FileDescriptorSet;
-
 fn main() {
     #[cfg(feature = "vendored-protoc")]
     std::env::set_var("PROTOC", protobuf_src::protoc());
@@ -34,20 +31,19 @@ fn build(dir: &Path, proto: &str) {
 
     prost_build
         .compile_well_known_types()
-        .type_attribute("google.protobuf.Empty","#[derive(serde_derive::Serialize, serde_derive::Deserialize)]")
-        .type_attribute("google.protobuf.FieldMask","#[derive(serde_derive::Serialize, serde_derive::Deserialize)]")
+        .enable_type_names()
+        .type_name_domain(&["."], "type.googleapis.com")
+        .type_attribute(
+            "google.protobuf.Empty",
+            "#[derive(serde_derive::Serialize, serde_derive::Deserialize)]",
+        )
+        .type_attribute(
+            "google.protobuf.FieldMask",
+            "#[derive(serde_derive::Serialize, serde_derive::Deserialize)]",
+        )
+        .message_attribute(".", "#[derive(::prost_wkt::MessageSerde)]")
         .file_descriptor_set_path(&descriptor_file)
         .out_dir(&out)
-        .compile_protos(
-            &[
-                source
-            ],
-            &["proto/".to_string()],
-        )
+        .compile_protos(&[source], &["proto/".to_string()])
         .unwrap();
-
-    let descriptor_bytes = std::fs::read(descriptor_file).unwrap();
-    let descriptor = FileDescriptorSet::decode(&descriptor_bytes[..]).unwrap();
-
-    prost_wkt_build::add_serde(out, descriptor);
 }