fix(endpoint): add default signing name (#615)

* fix(endpoint): add default signing name

* fix(endpoint): prioritize resolving endpoint default parameters and default signing name

Author: kuhe

smithy-typescript-codegen/build.gradle.kts

@@ -33,6 +33,7 @@ buildscript {
 dependencies {
     api("software.amazon.smithy:smithy-codegen-core:$smithyVersion")
     api("software.amazon.smithy:smithy-rules-engine:$smithyVersion")
+    api("software.amazon.smithy:smithy-aws-traits:$smithyVersion")
     api("software.amazon.smithy:smithy-waiters:$smithyVersion")
     implementation("software.amazon.smithy:smithy-protocol-test-traits:$smithyVersion")
 }

smithy-typescript-codegen/src/main/java/software/amazon/smithy/typescript/codegen/ServiceBareBonesClientGenerator.java

@@ -327,6 +327,14 @@ private void generateConstructor() {
             writer.write("let $L = __getRuntimeConfig(configuration);",
                     generateConfigVariable(configVariable));
 
+            if (service.hasTrait(EndpointRuleSetTrait.class)) {
+                configVariable++;
+                writer.write("let $L = $L($L);",
+                    generateConfigVariable(configVariable),
+                    "resolveClientEndpointParameters",
+                    generateConfigVariable(configVariable - 1));
+            }
+
             // Add runtime plugin "resolve" method calls. These are invoked one
             // after the other until all of the runtime plugins have been called.
             // Only plugins that have configuration are called. Each time the
@@ -350,14 +358,6 @@ private void generateConstructor() {
                 }
             }
 
-            if (service.hasTrait(EndpointRuleSetTrait.class)) {
-                configVariable++;
-                writer.write("let $L = $L($L);",
-                    generateConfigVariable(configVariable),
-                    "resolveClientEndpointParameters",
-                    generateConfigVariable(configVariable - 1));
-            }
-
             writer.write("super($L);", generateConfigVariable(configVariable));
             writer.write("this.config = $L;", generateConfigVariable(configVariable));
 

smithy-typescript-codegen/src/main/java/software/amazon/smithy/typescript/codegen/endpointsV2/EndpointsV2Generator.java

@@ -17,6 +17,8 @@
 
 import java.nio.file.Paths;
 import java.util.Map;
+import software.amazon.smithy.aws.traits.ServiceTrait;
+import software.amazon.smithy.aws.traits.auth.SigV4Trait;
 import software.amazon.smithy.build.FileManifest;
 import software.amazon.smithy.model.Model;
 import software.amazon.smithy.model.node.ObjectNode;
@@ -83,7 +85,13 @@ private void generateEndpointParameters() {
         );
 
         writer.write("");
-        writer.write("export type ClientResolvedEndpointParameters = ClientInputEndpointParameters;");
+        writer.openBlock(
+            "export type ClientResolvedEndpointParameters = ClientInputEndpointParameters & {",
+            "};",
+            () -> {
+                writer.write("defaultSigningName: string;");
+            }
+        );
         writer.write("");
 
         writer.openBlock(
@@ -98,6 +106,12 @@ private void generateEndpointParameters() {
                     ruleSet.getObjectMember("parameters").ifPresent(parameters -> {
                         parameters.accept(new RuleSetParametersVisitor(writer, true));
                     });
+                    ServiceTrait serviceTrait = service.getTrait(ServiceTrait.class).get();
+                    writer.write(
+                        "defaultSigningName: \"$L\",",
+                        service.getTrait(SigV4Trait.class).map(SigV4Trait::getName)
+                            .orElse(serviceTrait.getArnNamespace())
+                    );
                 });
             }
         );