codegen: use real sigv4a trait (#491)

* codegen: use real sigv4a trait

* include region auth param for sigv4a

.changelog/b39efe9f60e14df1b6fcab1c5795d0a4.json

@@ -0,0 +1,8 @@
+{
+    "id": "b39efe9f-60e1-4df1-b6fc-ab1c5795d0a4",
+    "type": "feature",
+    "description": "Add codegen definition for sigv4a trait.",
+    "modules": [
+        "."
+    ]
+}

codegen/gradle.properties

@@ -1,2 +1,2 @@
-smithyVersion=1.41.1
+smithyVersion=1.42.0
 smithyGradleVersion=0.7.0

codegen/smithy-go-codegen/src/main/java/software/amazon/smithy/go/codegen/integration/auth/SigV4ADefinition.java

@@ -0,0 +1,94 @@
+/*
+ * Copyright 2023 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License").
+ * You may not use this file except in compliance with the License.
+ * A copy of the License is located at
+ *
+ *  http://aws.amazon.com/apache2.0
+ *
+ * or in the "license" file accompanying this file. This file is distributed
+ * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
+ * express or implied. See the License for the specific language governing
+ * permissions and limitations under the License.
+ */
+
+package software.amazon.smithy.go.codegen.integration.auth;
+
+import static software.amazon.smithy.go.codegen.GoWriter.emptyGoTemplate;
+import static software.amazon.smithy.go.codegen.GoWriter.goTemplate;
+
+import java.util.Map;
+import software.amazon.smithy.aws.traits.auth.SigV4ATrait;
+import software.amazon.smithy.aws.traits.auth.SigV4Trait;
+import software.amazon.smithy.aws.traits.auth.UnsignedPayloadTrait;
+import software.amazon.smithy.go.codegen.GoWriter;
+import software.amazon.smithy.go.codegen.SmithyGoTypes;
+import software.amazon.smithy.go.codegen.integration.AuthSchemeDefinition;
+import software.amazon.smithy.go.codegen.integration.ProtocolGenerator;
+import software.amazon.smithy.model.shapes.OperationShape;
+import software.amazon.smithy.model.shapes.ServiceShape;
+import software.amazon.smithy.utils.MapUtils;
+
+/**
+ * Implements codegen for aws.auth#sigv4a.
+ */
+public class SigV4ADefinition implements AuthSchemeDefinition {
+    private static final Map<String, Object> COMMON_ENV = MapUtils.of(
+            "properties", SmithyGoTypes.Smithy.Properties,
+            "option", SmithyGoTypes.Auth.Option,
+            "schemeId", SmithyGoTypes.Auth.SchemeIDSigV4A,
+            "setSigningName", SmithyGoTypes.Transport.Http.SetSigV4ASigningName,
+            "setSigningRegions", SmithyGoTypes.Transport.Http.SetSigV4ASigningRegions
+    );
+
+    @Override
+    public GoWriter.Writable generateServiceOption(
+            ProtocolGenerator.GenerationContext context, ServiceShape service
+    ) {
+        var trait = service.expectTrait(SigV4ATrait.class);
+        return goTemplate("""
+                &$option:T{
+                    SchemeID: $schemeId:T,
+                    SignerProperties: func() $properties:T {
+                        var props $properties:T
+                        $setSigningName:T(&props, $name:S)
+                        $setSigningRegions:T(&props, []string{params.Region})
+                        return props
+                    }(),
+                },""",
+                COMMON_ENV,
+                MapUtils.of(
+                        "name", trait.getName()
+                ));
+    }
+
+    @Override
+    public GoWriter.Writable generateOperationOption(
+            ProtocolGenerator.GenerationContext context, OperationShape operation
+    ) {
+        var trait = context.getService().expectTrait(SigV4Trait.class);
+        return goTemplate("""
+                &$option:T{
+                    SchemeID: $schemeId:T,
+                    SignerProperties: func() $properties:T {
+                        var props $properties:T
+                        $setSigningName:T(&props, $name:S)
+                        $setSigningRegions:T(&props, []string{params.Region})
+                        $unsignedPayload:W
+                        return props
+                    }(),
+                },""",
+                COMMON_ENV,
+                MapUtils.of(
+                        "name", trait.getName(),
+                        "unsignedPayload", generateIsUnsignedPayload(operation)
+                ));
+    }
+
+    private GoWriter.Writable generateIsUnsignedPayload(OperationShape operation) {
+        return operation.hasTrait(UnsignedPayloadTrait.class)
+                ? goTemplate("$T(&props, true)", SmithyGoTypes.Transport.Http.SetIsUnsignedPayload)
+                : emptyGoTemplate();
+    }
+}

codegen/smithy-go-codegen/src/main/java/software/amazon/smithy/go/codegen/integration/auth/SigV4AuthScheme.java

@@ -16,6 +16,7 @@
 package software.amazon.smithy.go.codegen.integration.auth;
 
 import java.util.List;
+import software.amazon.smithy.aws.traits.auth.SigV4ATrait;
 import software.amazon.smithy.aws.traits.auth.SigV4Trait;
 import software.amazon.smithy.go.codegen.auth.AuthParameter;
 import software.amazon.smithy.go.codegen.integration.GoIntegration;
@@ -25,20 +26,20 @@
 import software.amazon.smithy.utils.ListUtils;
 
 /**
- * Code generation for SigV4.
+ * Code generation for SigV4/SigV4A.
  */
 public class SigV4AuthScheme implements GoIntegration {
-    private boolean isSigV4Service(Model model, ServiceShape service) {
-        return service.hasTrait(SigV4Trait.class);
+    private boolean isSigV4XService(Model model, ServiceShape service) {
+        return service.hasTrait(SigV4Trait.class) || service.hasTrait(SigV4ATrait.class);
     }
 
     @Override
     public List<RuntimeClientPlugin> getClientPlugins() {
-        // FUTURE: add default Region client option, scheme definition, and resolver - we need a more structured way of
-        //         suppressing elements of a GoIntegration before we do so, for now those live on the SDK side
+        // FUTURE: add default Region client option and scheme definitions - we need a more structured way of
+        //         suppressing elements of a GoIntegration before we do so, for now those are registered SDK-side
         return ListUtils.of(
                 RuntimeClientPlugin.builder()
-                        .servicePredicate(this::isSigV4Service)
+                        .servicePredicate(this::isSigV4XService)
                         .addAuthParameter(AuthParameter.REGION)
                         .build()
         );