Fix duplicate content-type in server response (#1163)

Signed-off-by: Guy Margalit <[email protected]>
smithy-lang · Feb 7, 2022 · 2a68774 · 2a68774
1 parent 25c50a5
commit 2a68774
Showing 1 changed file with 15 additions and 13 deletions.
diff --git a/...oftware/amazon/smithy/rust/codegen/server/smithy/protocols/ServerHttpProtocolGenerator.kt b/...oftware/amazon/smithy/rust/codegen/server/smithy/protocols/ServerHttpProtocolGenerator.kt
@@ -492,6 +492,21 @@ private class ServerHttpProtocolImplGenerator(
      * The `Content-Type` header is also set according to the protocol and the contents of the shape to be serialized.
      */
     private fun RustWriter.serverRenderResponseHeaders(operationShape: OperationShape, errorShape: StructureShape? = null) {
+        val bindingGenerator = ServerResponseBindingGenerator(protocol, codegenContext, operationShape)
+        val addHeadersFn = bindingGenerator.generateAddHeadersFn(errorShape ?: operationShape)
+        if (addHeadersFn != null) {
+            // notice that we need to borrow the output only for output shapes but not for error shapes
+            val outputOwnedOrBorrow = if (errorShape == null) "&output" else "output"
+            rust(
+                """
+                builder = #{T}($outputOwnedOrBorrow, builder)?;
+                """.trimIndent(),
+                addHeadersFn
+            )
+        }
+
+        // set the content type header *after* the response bindings headers have been set
+        // to allow operations that bind a member to content-type to take precedence
         val contentType = httpBindingResolver.responseContentType(operationShape)
         if (contentType != null) {
             rustTemplate(
@@ -505,19 +520,6 @@ private class ServerHttpProtocolImplGenerator(
                 *codegenScope
             )
         }
-
-        val bindingGenerator = ServerResponseBindingGenerator(protocol, codegenContext, operationShape)
-        val addHeadersFn = bindingGenerator.generateAddHeadersFn(errorShape ?: operationShape)
-        if (addHeadersFn != null) {
-            // notice that we need to borrow the output only for output shapes but not for error shapes
-            val outputOwnedOrBorrow = if (errorShape == null) "&output" else "output"
-            rust(
-                """
-                builder = #{T}($outputOwnedOrBorrow, builder)?;
-                """.trimIndent(),
-                addHeadersFn
-            )
-        }
     }
 
     private fun serverRenderBindingSerializer(