From 5f29f28cfb97bd50d0a7a9c33ad4a6e422b53506 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=EA=B0=95=EB=8F=99=EC=9C=A4?= <kdy1997.dev@gmail.com>
Date: Sat, 25 Jan 2020 19:20:43 +0900
Subject: [PATCH] Make #[derive(Schema)] no-op when openapi is disabled

---
 examples/futures.rs   | 2 +-
 macros/src/lib.rs     | 3 +++
 src/lib.rs            | 2 +-
 src/openapi/entity.rs | 4 +++-
 4 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/examples/futures.rs b/examples/futures.rs
index 2b2b01c6..c46e4537 100644
--- a/examples/futures.rs
+++ b/examples/futures.rs
@@ -18,7 +18,7 @@ async fn sleepy(seconds: Seconds) -> Result<impl rweb::Reply, Infallible> {
 }
 
 /// A newtype to enforce our maximum allowed seconds.
-#[cfg_attr(feature = "openapi", derive(Schema))]
+#[derive(Schema)]
 struct Seconds(u64);
 
 impl FromStr for Seconds {
diff --git a/macros/src/lib.rs b/macros/src/lib.rs
index 9d1612f9..1ce626e1 100644
--- a/macros/src/lib.rs
+++ b/macros/src/lib.rs
@@ -84,6 +84,9 @@ pub fn router(
 /// See documentation of Entity for details and examples.
 #[proc_macro_derive(Schema, attributes(schema))]
 pub fn derive_schema(input: proc_macro::TokenStream) -> proc_macro::TokenStream {
+    if !cfg!(feature = "openapi") {
+        return "".parse().unwrap();
+    }
     let input = syn::parse::<syn::DeriveInput>(input).expect("failed to parse derive input");
     openapi::derive_schema(input).into()
 }
diff --git a/src/lib.rs b/src/lib.rs
index ee6615fe..7093186f 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -293,7 +293,7 @@
 //! }
 //!
 //!
-//! #[cfg_attr(feature = "openapi", derive(Schema))]
+//! #[derive(Schema)]
 //! struct User {
 //!    id: String,
 //! }
diff --git a/src/openapi/entity.rs b/src/openapi/entity.rs
index a442adcc..c8d8645b 100644
--- a/src/openapi/entity.rs
+++ b/src/openapi/entity.rs
@@ -15,7 +15,9 @@ pub type Responses = BTreeMap<Cow<'static, str>, Response>;
 ///
 /// # `#[derive(Schema)]`
 ///
-/// It implements [Entity] for the struct or enum.
+/// It implements [Entity] for the struct or enum. Note that it's recommended to
+/// use `derive(Schema)` even when you are not using openapi, as it is noop when
+/// cargo feature openapi is disabled.
 ///
 /// ## Overriding description
 ///