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diff --git a/Cargo.lock b/Cargo.lock
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -5639,6 +5639,16 @@
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "711b9620af191e0cdc7468a8d14e709c3dcdb115b36f838e601583af800a370a"
+[[package]]
+name = "util_macros"
+version = "0.1.0"
+dependencies = [
+ "quote",
+ "serde",
+ "serde_json",
+ "syn 1.0.109",
+]
+
[[package]]
name = "uuid"
version = "1.8.0"
diff --git a/shared/util_macros/Cargo.toml b/shared/util_macros/Cargo.toml
new file mode 100644
--- /dev/null
+++ b/shared/util_macros/Cargo.toml
@@ -0,0 +1,15 @@
+[package]
+name = "util_macros"
+version = "0.1.0"
+edition.workspace = true
+license.workspace = true
+homepage.workspace = true
+
+[lib]
+proc-macro = true
+
+[dependencies]
+serde = { workspace = true, features = ["derive"] }
+serde_json = { workspace = true }
+syn = "1.0"
+quote = "1.0"
diff --git a/shared/util_macros/src/lib.rs b/shared/util_macros/src/lib.rs
new file mode 100644
--- /dev/null
+++ b/shared/util_macros/src/lib.rs
@@ -0,0 +1,62 @@
+extern crate proc_macro;
+use proc_macro::TokenStream;
+
+mod tag_aware_deserialize;
+
+/// Fixes [`serde::Deserialize`] implementation for deserializing
+/// untagged enums of internally tagged structs. Original implementation
+/// totally ignores the `tag` attribute when deserializing enum variants.
+///
+/// This derive requires two serde attributes to be present:
+/// `#[serde(tag = "type", remote = "Self")]`
+///
+/// ### Example
+/// ```
+/// use serde::{Deserialize, Serialize};
+/// use util_macros::TagAwareDeserialize;
+///
+/// // Note that FirstStruct and SecondStruct have identical fields
+/// // They're only distinguishable by 'tag'
+/// #[derive(Debug, Serialize, Deserialize, TagAwareDeserialize)]
+/// #[serde(tag = "type", remote = "Self")]
+/// struct FirstStruct {
+/// foo: String,
+/// bar: String,
+/// }
+/// #[derive(Debug, Serialize, Deserialize, TagAwareDeserialize)]
+/// #[serde(tag = "type", remote = "Self")]
+/// struct SecondStruct {
+/// foo: String,
+/// bar: String,
+/// }
+///
+/// #[derive(Debug, Serialize, Deserialize)]
+/// #[serde(untagged)]
+/// enum EitherStruct {
+/// // Note that FirstStruct is BEFORE SecondStruct
+/// FirstStruct(FirstStruct),
+/// SecondStruct(SecondStruct),
+/// }
+///
+/// let input = SecondStruct {
+/// foo: "a".to_string(),
+/// bar: "b".to_string(),
+/// };
+/// let serialized = serde_json::to_string(&input).unwrap();
+///
+/// let deserialized: EitherStruct = serde_json::from_str(&serialized).unwrap();
+/// match deserialized {
+/// EitherStruct::SecondStruct(result) => {
+/// println!("Successfully deserialized {:?}", result);
+/// },
+/// other => {
+/// println!("Wrong variant was deserialized: {:?}", other);
+/// }
+/// };
+///
+/// ```
+#[proc_macro_derive(TagAwareDeserialize)]
+pub fn tag_aware_deserialize_macro_derive(input: TokenStream) -> TokenStream {
+ let ast = syn::parse(input).unwrap();
+ tag_aware_deserialize::impl_tag_aware_deserialize_macro(&ast)
+}
diff --git a/shared/util_macros/src/tag_aware_deserialize.rs b/shared/util_macros/src/tag_aware_deserialize.rs
new file mode 100644
--- /dev/null
+++ b/shared/util_macros/src/tag_aware_deserialize.rs
@@ -0,0 +1,40 @@
+use proc_macro::TokenStream;
+use quote::quote;
+
+pub fn impl_tag_aware_deserialize_macro(ast: &syn::DeriveInput) -> TokenStream {
+ let name = &ast.ident;
+
+ let gen = quote! {
+ impl<'de> serde::de::Deserialize<'de> for #name {
+ fn deserialize<D>(deserializer: D) -> std::result::Result<Self, D::Error>
+ where
+ D: serde::Deserializer<'de>,
+ {
+ use serde::de::Error;
+
+ let this = serde_json::Value::deserialize(deserializer)?;
+ if let Some(found_tag) = this.get("type") {
+ if found_tag == stringify!(#name) {
+ // now we can run _original_ deserialize
+ return match #name::deserialize(this) {
+ Ok(object) => Ok(object),
+ Err(err) => Err(Error::custom(err)),
+ };
+ }
+ }
+ Err(Error::custom(format!("Deserialized object is not a '{}'", stringify!(#name))))
+ }
+ }
+
+ // We need a dummy `Serialize` impl for `remote = "Self"` to work
+ impl Serialize for #name {
+ fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+ where
+ S: serde::Serializer,
+ {
+ Self::serialize(self, serializer)
+ }
+ }
+ };
+ gen.into()
+}

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