Allow the OpenDDS schema ID to be partially overridden. (#710)

Rules:
* The schema ID is set by the `id` property, falling back to `rename`.
* The schema ID is always prefixed by a URL base.
* The schema name is set by the `rename` property, falling back to `id`.
* The schema title is set by the `title` property, falling back to
`rename`, then `id`.
* If the name or title are automatically created from the ID, remove
characters that might choke a code generator, such as ' ' or '/'.
V3_GIT_ORIGIN_REV_ID: fac46a0849c2f36642daeca2971fdce7d253256a

v3/crates/utils/opendds-derive/src/container.rs

@@ -6,7 +6,7 @@ use crate::MacroResult;
 
 lazy_static::lazy_static! {
     /// Characters that we reject when constructing titles from schema names.
-    static ref INVALID_TITLE_CHARACTER: regex::Regex = regex::Regex::new("[^0-9A-Za-z_]").unwrap();
+    static ref INVALID_NAME_CHARACTER: regex::Regex = regex::Regex::new("[^0-9A-Za-z_]").unwrap();
 }
 
 /// JSON schema attributes
@@ -14,6 +14,7 @@ lazy_static::lazy_static! {
 #[darling(default)]
 struct JsonSchemaOpts {
     rename: Option<String>,
+    id: Option<String>,
     title: Option<String>,
     example: Option<syn::Path>,
 }
@@ -72,6 +73,7 @@ pub struct Container<'a> {
 
 pub struct JsonSchemaMetadata {
     pub schema_name: String,
+    pub id: String,
     pub title: String,
     pub description: Option<String>,
     pub example: Option<syn::Path>,
@@ -98,21 +100,33 @@ impl<'a> Container<'a> {
                 );
             }
         };
+
+        // Rules:
+        // * The schema ID is set by the `id` property, falling back to `rename`.
+        // * The schema ID is always prefixed by a URL base.
+        // * The schema name is set by the `rename` property, falling back to `id`.
+        // * The schema title is set by the `title` property, falling back to `rename`, then `id`.
+        // * If the name or title are automatically created from the ID, remove characters that
+        //   might choke a code generator, such as ' ' or '/'.
+
+        let id = json_schema_opts
+            .id
+            .or_else(|| json_schema_opts.rename.clone())
+            .unwrap_or_else(|| input.ident.to_string());
+        let schema_id = format!("https://hasura.io/jsonschemas/metadata/{id}");
         let schema_name = json_schema_opts
             .rename
-            .unwrap_or_else(|| input.ident.to_string());
-        let schema_title = json_schema_opts.title.or(doc_title).unwrap_or_else(|| {
-            // If the title is automatically created from the schema name, remove characters that
-            // might choke a code generator, such as ' ' or '/'.
-            INVALID_TITLE_CHARACTER
-                .replace_all(&schema_name, "_")
-                .to_string()
-        });
+            .unwrap_or_else(|| INVALID_NAME_CHARACTER.replace_all(&id, "_").to_string());
+        let schema_title = json_schema_opts
+            .title
+            .or(doc_title)
+            .unwrap_or_else(|| schema_name.clone());
         let schema_example = json_schema_opts.example;
 
         let json_schema_metadata = JsonSchemaMetadata {
             schema_name,
             title: schema_title,
+            id: schema_id,
             description: doc_description,
             example: schema_example,
         };

v3/crates/utils/opendds-derive/src/helpers.rs

@@ -93,6 +93,7 @@ pub fn apply_schema_metadata(
     schema_expr: &proc_macro2::TokenStream,
     json_schema_metadata: JsonSchemaMetadata,
 ) -> proc_macro2::TokenStream {
+    let id = json_schema_metadata.id;
     let title = json_schema_metadata.title;
     let description = json_schema_metadata
         .description
@@ -112,8 +113,8 @@ pub fn apply_schema_metadata(
         };
         let mut schema_object = schema.into_object();
         let metadata = schema_object.metadata();
+        metadata.id = Some(#id.to_owned());
         metadata.title = Some(#title.to_owned());
-        metadata.id = Some(format!("https://hasura.io/jsonschemas/metadata/{}", Self::_schema_name()));
         #description
         #examples
         schemars::schema::Schema::Object(schema_object)

v3/crates/utils/opendds-derive/src/lib.rs

@@ -33,7 +33,7 @@ fn impl_opendd(input: &DeriveInput) -> MacroResult<proc_macro2::TokenStream> {
         Data::Struct(struct_data) => struct_derive::impl_opendd_struct(name, &struct_data),
     };
     let json_schema_metadata = cont.json_schema_metadata;
-    let schema_name = &json_schema_metadata.schema_name.to_string();
+    let schema_name = json_schema_metadata.schema_name.to_string();
     let impl_json_schema = helpers::apply_schema_metadata(&json_schema, json_schema_metadata);
     let (impl_generics, ty_generics, where_clause) = input.generics.split_for_impl();
     Ok(quote! {