From 48a85316a4dbfee4998613dd03ae4c6c3274fec0 Mon Sep 17 00:00:00 2001
From: Harry Barber <106155934+hlbarber@users.noreply.github.com>
Date: Thu, 11 Aug 2022 23:56:27 +0100
Subject: [PATCH] Make OperationExtension hold a &'static str for the absolute
 shape ID (#1631)

---
 .../ServerOperationHandlerGenerator.kt        |  5 +--
 .../aws-smithy-http-server/src/extension.rs   | 40 +++++++++++++------
 2 files changed, 29 insertions(+), 16 deletions(-)

diff --git a/codegen-server/src/main/kotlin/software/amazon/smithy/rust/codegen/server/smithy/generators/ServerOperationHandlerGenerator.kt b/codegen-server/src/main/kotlin/software/amazon/smithy/rust/codegen/server/smithy/generators/ServerOperationHandlerGenerator.kt
index 3998eab98..33f040b65 100644
--- a/codegen-server/src/main/kotlin/software/amazon/smithy/rust/codegen/server/smithy/generators/ServerOperationHandlerGenerator.kt
+++ b/codegen-server/src/main/kotlin/software/amazon/smithy/rust/codegen/server/smithy/generators/ServerOperationHandlerGenerator.kt
@@ -115,9 +115,8 @@ open class ServerOperationHandlerGenerator(
                         $callImpl
                         let output_wrapper: $outputWrapperName = output_inner.into();
                         let mut response = output_wrapper.into_response();
-                        response.extensions_mut().insert(
-                            #{SmithyHttpServer}::extension::OperationExtension::new("${operation.id.namespace}", "$operationName")
-                        );
+                        let operation_ext = #{SmithyHttpServer}::extension::OperationExtension::new("${operation.id.namespace}##$operationName").expect("malformed absolute shape ID");
+                        response.extensions_mut().insert(operation_ext);
                         response.map(#{SmithyHttpServer}::body::boxed)
                     }
                     """,
diff --git a/rust-runtime/aws-smithy-http-server/src/extension.rs b/rust-runtime/aws-smithy-http-server/src/extension.rs
index 8dcb1ad58..d221d4a99 100644
--- a/rust-runtime/aws-smithy-http-server/src/extension.rs
+++ b/rust-runtime/aws-smithy-http-server/src/extension.rs
@@ -50,6 +50,8 @@
 
 use std::ops::Deref;
 
+use thiserror::Error;
+
 use crate::request::RequestParts;
 
 /// Extension type used to store information about Smithy operations in HTTP responses.
@@ -58,19 +60,31 @@ use crate::request::RequestParts;
 /// request fails to deserialize into the modeled operation input.
 #[derive(Debug, Clone)]
 pub struct OperationExtension {
-    /// Smithy model namespace.
+    absolute: &'static str,
+
     namespace: &'static str,
-    /// Smithy operation name.
-    operation_name: &'static str,
+    name: &'static str,
+}
+
+/// An error occurred when parsing an absolute operation shape ID.
+#[derive(Debug, Clone, Error)]
+#[non_exhaustive]
+pub enum ParseError {
+    #[error("# was not found - missing namespace")]
+    MissingNamespace,
 }
 
 impl OperationExtension {
-    /// Creates a new `OperationExtension`.
-    pub fn new(namespace: &'static str, operation_name: &'static str) -> Self {
-        Self {
+    /// Creates a new [`OperationExtension`] from the absolute shape ID of the operation.
+    pub fn new(absolute_operation_id: &'static str) -> Result<Self, ParseError> {
+        let (namespace, name) = absolute_operation_id
+            .split_once('#')
+            .ok_or(ParseError::MissingNamespace)?;
+        Ok(Self {
+            absolute: absolute_operation_id,
             namespace,
-            operation_name,
-        }
+            name,
+        })
     }
 
     /// Returns the Smithy model namespace.
@@ -79,13 +93,13 @@ impl OperationExtension {
     }
 
     /// Returns the Smithy operation name.
-    pub fn operation_name(&self) -> &'static str {
-        self.operation_name
+    pub fn name(&self) -> &'static str {
+        self.name
     }
 
-    /// Returns the current operation formatted as `<namespace>#<operation_name>`.
-    pub fn operation(&self) -> String {
-        format!("{}#{}", self.namespace, self.operation_name)
+    /// Returns the absolute operation shape ID.
+    pub fn absolute(&self) -> &'static str {
+        self.absolute
     }
 }
 
-- 
GitLab