feat(session_config): allow add alias for parameter name

src/common/proc_macro/src/session_config.rs

@@ -21,6 +21,7 @@ use syn::DeriveInput;
 #[derive(FromAttributes)]
 struct Parameter {
     pub rename: Option<syn::LitStr>,
+    pub alias: Option<syn::Expr>,
     pub default: syn::Expr,
     pub flags: Option<syn::LitStr>,
     pub check_hook: Option<syn::Expr>,
@@ -39,6 +40,7 @@ pub(crate) fn derive_config(input: DeriveInput) -> TokenStream {
     let mut get_match_branches = vec![];
     let mut reset_match_branches = vec![];
     let mut show_all_list = vec![];
+    let mut alias_to_entry_name_branches = vec![];
 
     for field in fields {
         let field_ident = field.ident.expect_or_abort("Field need to be named");
@@ -62,6 +64,7 @@ pub(crate) fn derive_config(input: DeriveInput) -> TokenStream {
             Parameter::from_attributes(&field.attrs).expect_or_abort("Failed to parse attribute");
         let Parameter {
             rename,
+            alias,
             default,
             flags,
             check_hook: check_hook_name,
@@ -78,6 +81,12 @@ pub(crate) fn derive_config(input: DeriveInput) -> TokenStream {
             quote! {stringify!(#ident)}
         };
 
+        if let Some(alias) = alias {
+            alias_to_entry_name_branches.push(quote! {
+                #alias => #entry_name.to_string(),
+            })
+        }
+
         let flags = flags.map(|f| f.value()).unwrap_or_default();
         let flags: Vec<_> = flags.split('|').map(|str| str.trim()).collect();
 
@@ -236,6 +245,13 @@ pub(crate) fn derive_config(input: DeriveInput) -> TokenStream {
                 Default::default()
             }
 
+            fn alias_to_entry_name(key_name: &str) -> String {
+                match key_name {
+                    #(#alias_to_entry_name_branches)*
+                    _ => key_name.to_string(),
+                }
+            }
+
             #(#struct_impl_get)*
 
             #(#struct_impl_set)*
@@ -244,6 +260,7 @@ pub(crate) fn derive_config(input: DeriveInput) -> TokenStream {
 
             /// Set a parameter given it's name and value string.
             pub fn set(&mut self, key_name: &str, value: String, reporter: &mut impl ConfigReporter) -> SessionConfigResult<()> {
+                let key_name = Self::alias_to_entry_name(key_name);
                 match key_name.to_ascii_lowercase().as_ref() {
                     #(#set_match_branches)*
                     _ => Err(SessionConfigError::UnrecognizedEntry(key_name.to_string())),
@@ -252,6 +269,7 @@ pub(crate) fn derive_config(input: DeriveInput) -> TokenStream {
 
             /// Get a parameter by it's name.
             pub fn get(&self, key_name: &str) -> SessionConfigResult<String> {
+                let key_name = Self::alias_to_entry_name(key_name);
                 match key_name.to_ascii_lowercase().as_ref() {
                     #(#get_match_branches)*
                     _ => Err(SessionConfigError::UnrecognizedEntry(key_name.to_string())),
@@ -260,6 +278,7 @@ pub(crate) fn derive_config(input: DeriveInput) -> TokenStream {
 
             /// Reset a parameter by it's name.
             pub fn reset(&mut self, key_name: &str, reporter: &mut impl ConfigReporter) -> SessionConfigResult<()> {
+                let key_name = Self::alias_to_entry_name(key_name);
                 match key_name.to_ascii_lowercase().as_ref() {
                     #(#reset_match_branches)*
                     _ => Err(SessionConfigError::UnrecognizedEntry(key_name.to_string())),

src/common/src/session_config/mod.rs

@@ -304,3 +304,25 @@ pub trait ConfigReporter {
 impl ConfigReporter for () {
     fn report_status(&mut self, _key: &str, _new_val: String) {}
 }
+
+#[cfg(test)]
+mod test {
+    use super::*;
+
+    #[derive(SessionConfig)]
+    struct TestConfig {
+        #[parameter(default = 1, alias = "test_param_alias" | "alias_param_test")]
+        test_param: i32,
+    }
+
+    #[test]
+    fn test_session_config_alias() {
+        let mut config = TestConfig::default();
+        config.set("test_param", "2".to_string(), &mut ()).unwrap();
+        assert_eq!(config.get("test_param_alias").unwrap(), "2");
+        config
+            .set("alias_param_test", "3".to_string(), &mut ())
+            .unwrap();
+        assert_eq!(config.get("test_param_alias").unwrap(), "3");
+    }
+}