UnsupportedMethod error type for try_from(..)

axum/src/routing/method_filter.rs

@@ -1,6 +1,6 @@
+use std::{fmt, fmt::{Debug, Formatter}};
 use bitflags::bitflags;
 use http::Method;
-use axum_core::Error;
 
 bitflags! {
     /// A filter that matches one or more HTTP methods.
@@ -24,10 +24,29 @@ bitflags! {
     }
 }
 
+#[derive(Debug)]
+pub struct UnsupportedMethod {
+    method: http::Method,
+}
+
+impl UnsupportedMethod {
+    pub fn method(&self) -> &http::Method {
+        &self.method
+    }
+}
+
+impl fmt::Display for UnsupportedMethod {
+    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
+        write!(f, "Failed to match http method: {}", self.method.as_str())
+    }
+}
+
+impl std::error::Error for UnsupportedMethod {}
+
 impl TryFrom<Method> for MethodFilter {
-    type Error = Error;
+    type Error = UnsupportedMethod;
 
-    fn try_from(m: Method) -> Result<Self, Error> {
+    fn try_from(m: Method) -> Result<Self, UnsupportedMethod> {
         match m {
             Method::DELETE => Ok(MethodFilter::DELETE),
             Method::GET => Ok(MethodFilter::GET),
@@ -37,7 +56,7 @@ impl TryFrom<Method> for MethodFilter {
             Method::POST => Ok(MethodFilter::POST),
             Method::PUT => Ok(MethodFilter::PUT),
             Method::TRACE => Ok(MethodFilter::TRACE),
-            _ => Err(Error::new("could not map method")),
+            _ => Err(UnsupportedMethod { method: m}),
         }
     }
 }

axum/src/routing/tests/mod.rs

@@ -19,6 +19,7 @@ use std::{
     task::{Context, Poll},
     time::Duration,
 };
+use std::fmt::format;
 use tower::{service_fn, timeout::TimeoutLayer, ServiceBuilder, ServiceExt};
 use tower_http::{auth::RequireAuthorizationLayer, limit::RequestBodyLimitLayer};
 use tower_service::Service;
@@ -731,4 +732,10 @@ fn from_http_method() {
     assert_eq!(MethodFilter::try_from(Method::POST).unwrap(), MethodFilter::POST);
     assert_eq!(MethodFilter::try_from(Method::PUT).unwrap(), MethodFilter::PUT);
     assert_eq!(MethodFilter::try_from(Method::TRACE).unwrap(), MethodFilter::TRACE);
+    match MethodFilter::try_from(http::Method::CONNECT) {
+        Ok(_) => panic!("test failed, the method 'CONNECT' is not supported"),
+        Err(e) => {
+            assert!(format!("{}", e).contains(e.method().as_str()))
+        }
+    }
 }