Add new macro to generate the get method

ibihf-macros/src/lib.rs

@@ -30,3 +30,56 @@ pub fn derive(input: TokenStream) -> TokenStream {
     };
     output.into()
 }
+
+#[derive(FromDeriveInput, Default)]
+#[darling(default, attributes(table_names))]
+struct TableNameOpts {
+  table_name: String,
+  name_func: String,
+  name_table_name: String,
+  name_table_name_fk: String,
+}
+
+#[proc_macro_derive(NameTableName, attributes(table_names))]
+pub fn derive_get(input: TokenStream) -> TokenStream {
+    let input = parse_macro_input!(input);
+    let opts = TableNameOpts::from_derive_input(&input).expect("Wrong options");
+    let DeriveInput { ident, .. } = input;
+
+    let table_name = opts.table_name;
+    let name_table_name = opts.name_table_name;
+    let name_table_name_fk = opts.name_table_name_fk;
+    let name_func = opts.name_func;
+    let answer = quote! {
+        //const TABLE_NAME: &'static str = #table_name;
+        const NAME_TABLE_NAME: &'static str = #name_table_name;
+        const NAME_TABLE_FK_NAME: &'static str = #name_table_name_fk;
+    };
+
+    let query = format!(r#"
+SELECT
+  {0}.*,
+  {1}({0}.id, $2) AS name
+FROM {0}
+WHERE {0}.id = $1;"#,
+      table_name,
+      name_func,
+    );
+    let output = quote! {
+        impl NameTableName for #ident {
+            #answer
+        }
+        impl #ident {
+          pub async fn get(pool: &sqlx::PgPool, id: i32, lang: i32) -> Result<Option<Self>, sqlx::Error> {
+            sqlx::query_as!(
+              #ident,
+              #query,
+              id, lang
+            )
+            .fetch_optional(pool)
+            .await
+          }
+        }
+    };
+    output.into()
+}