support custom properties

core/src/v3/schema.rs

@@ -1,5 +1,5 @@
 use super::{invalid_referenceor, v2};
-use std::ops::Deref;
+use std::{iter::FromIterator, ops::Deref};
 
 impl From<v2::DefaultSchemaRaw> for openapiv3::ReferenceOr<Box<openapiv3::Schema>> {
     fn from(v2: v2::DefaultSchemaRaw) -> Self {
@@ -30,7 +30,7 @@ impl From<v2::DefaultSchemaRaw> for openapiv3::ReferenceOr<openapiv3::Schema> {
                         description: v2.description,
                         discriminator: None,
                         default: None,
-                        extensions: indexmap::IndexMap::new(),
+                        extensions: indexmap::IndexMap::from_iter(v2.extensions.into_iter()),
                     },
                     schema_kind: {
                         if let Some(data_type) = v2.data_type {

macros/src/actix.rs

@@ -756,6 +756,38 @@ fn extract_example(attrs: &[Attribute]) -> Option<String> {
     None
 }
 
+fn extract_extensions(attrs: &[Attribute]) -> proc_macro2::TokenStream {
+    let mut ext_attrs = HashMap::new();
+    let attrs = extract_openapi_attrs(attrs);
+    for attr in attrs.flat_map(|attr| attr.into_iter()) {
+        if let NestedMeta::Meta(Meta::NameValue(nv)) = attr {
+            if let Some(id) = nv.path.get_ident() {
+                let s_id = id.to_string();
+                if s_id.starts_with('x') {
+                    ext_attrs.insert(id.clone(), nv.lit);
+                }
+            }
+        }
+    }
+
+    if ext_attrs.is_empty() {
+        quote! { std::collections::BTreeMap::new() }
+    } else {
+        // ext_attrs
+        let mut items = quote!();
+        for (k, v) in ext_attrs {
+            let lit_key = syn::LitStr::new(&k.to_string().replace('_', "-"), k.span());
+            items.extend(quote!((#lit_key.to_string(),serde_json::to_value(&#v).unwrap()),));
+        }
+
+        let gen = quote! {
+            std::collections::BTreeMap::from([#items])
+        };
+
+        gen
+    }
+}
+
 /// Actual parser and emitter for `api_v2_schema` macro.
 pub fn emit_v2_definition(input: TokenStream) -> TokenStream {
     let item_ast = match crate::expect_struct_or_enum(input) {
@@ -779,6 +811,8 @@ pub fn emit_v2_definition(input: TokenStream) -> TokenStream {
         quote!(None)
     };
 
+    let extensions = extract_extensions(&item_ast.attrs);
+
     let props = SerdeProps::from_item_attrs(&item_ast.attrs);
 
     let name = &item_ast.ident;
@@ -846,6 +880,7 @@ pub fn emit_v2_definition(input: TokenStream) -> TokenStream {
         let mut schema = DefaultSchemaRaw {
             name: Some(#schema_name.into()),
             example: #example,
+            extensions:#extensions,
             ..Default::default()
         };
     };
@@ -855,6 +890,7 @@ pub fn emit_v2_definition(input: TokenStream) -> TokenStream {
         let mut schema = DefaultSchemaRaw {
             name: Some(Self::__paperclip_schema_name()), // Add name for later use.
             example: #example,
+            extensions:#extensions,
             .. Default::default()
         };
     };
@@ -1572,12 +1608,17 @@ fn handle_field_struct(
             quote!({})
         };
 
+        let extensions = extract_extensions(&field.attrs);
+
         let gen = if !SerdeFlatten::exists(&field.attrs) {
             quote!({
                 let mut s = #ty_ref::raw_schema();
                 if !#docs.is_empty() {
                     s.description = Some(#docs.to_string());
                 }
+
+                s.extensions = #extensions;
+
                 #example;
                 schema.properties.insert(#field_name.into(), s.into());
 
@@ -1587,9 +1628,9 @@ fn handle_field_struct(
             })
         } else {
             quote!({
-                let s = #ty_ref::raw_schema();
+                let mut s = #ty_ref::raw_schema();
                 schema.properties.extend(s.properties);
-
+                s.extensions = #extensions;
                 if #ty_ref::required() {
                     schema.required.extend(s.required);
                 }

macros/src/core.rs

@@ -320,6 +320,11 @@ fn schema_fields(name: &Ident, is_ref: bool) -> proc_macro2::TokenStream {
         pub required: std::collections::BTreeSet<String>,
     ));
 
+    gen.extend(quote!(
+        #[serde(skip_serializing_if = "std::collections::BTreeMap::is_empty", default = "std::collections::BTreeMap::default")]
+        pub extensions: std::collections::BTreeMap<String, serde_json::Value>,
+    ));
+
     if is_ref {
         gen.extend(quote!(
             #[serde(skip)]