Add jsonName trait docs

Author: JordonPhillips

smithy-docgen-core/src/main/java/software/amazon/smithy/docgen/core/integrations/BuiltinsIntegration.java

@@ -17,6 +17,7 @@
 import software.amazon.smithy.docgen.core.interceptors.ExternalDocsInterceptor;
 import software.amazon.smithy.docgen.core.interceptors.IdempotencyInterceptor;
 import software.amazon.smithy.docgen.core.interceptors.InternalInterceptor;
+import software.amazon.smithy.docgen.core.interceptors.JsonNameInterceptor;
 import software.amazon.smithy.docgen.core.interceptors.LengthInterceptor;
 import software.amazon.smithy.docgen.core.interceptors.NoReplaceBindingInterceptor;
 import software.amazon.smithy.docgen.core.interceptors.NoReplaceOperationInterceptor;
@@ -75,6 +76,7 @@ public List<? extends CodeInterceptor<? extends CodeSection, DocWriter>> interce
         return List.of(
                 new OperationAuthInterceptor(),
                 new ApiKeyAuthInterceptor(),
+                new JsonNameInterceptor(),
                 new PaginationInterceptor(),
                 new RequestCompressionInterceptor(),
                 new NoReplaceBindingInterceptor(),

smithy-docgen-core/src/main/java/software/amazon/smithy/docgen/core/interceptors/JsonNameInterceptor.java

@@ -0,0 +1,39 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package software.amazon.smithy.docgen.core.interceptors;
+
+import software.amazon.smithy.docgen.core.sections.ProtocolSection;
+import software.amazon.smithy.docgen.core.writers.DocWriter;
+import software.amazon.smithy.model.shapes.ShapeId;
+import software.amazon.smithy.model.traits.JsonNameTrait;
+import software.amazon.smithy.utils.SmithyInternalApi;
+
+/**
+ * Adds a member's <a href="https://smithy.io/2.0/spec/protocol-traits.html#jsonname-trait">
+ * jsonName</a> to the {@link ProtocolSection} if the protocol supports it.
+ */
+@SmithyInternalApi
+public final class JsonNameInterceptor extends ProtocolTraitInterceptor<JsonNameTrait> {
+
+    @Override
+    protected Class<JsonNameTrait> getTraitClass() {
+        return JsonNameTrait.class;
+    }
+
+    @Override
+    protected ShapeId getTraitId() {
+        return JsonNameTrait.ID;
+    }
+
+    @Override
+    public void write(DocWriter writer, String previousText, ProtocolSection section, JsonNameTrait trait) {
+        writer.putContext("jsonKeyName", "JSON key name:");
+        writer.write("""
+                ${jsonKeyName:B} $`
+
+                $L""", trait.getValue(), previousText);
+    }
+}

smithy-docgen-core/src/main/java/software/amazon/smithy/docgen/core/interceptors/ProtocolTraitInterceptor.java

@@ -0,0 +1,54 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package software.amazon.smithy.docgen.core.interceptors;
+
+import software.amazon.smithy.docgen.core.sections.ProtocolSection;
+import software.amazon.smithy.docgen.core.writers.DocWriter;
+import software.amazon.smithy.model.shapes.ShapeId;
+import software.amazon.smithy.model.traits.ProtocolDefinitionTrait;
+import software.amazon.smithy.model.traits.Trait;
+import software.amazon.smithy.utils.CodeInterceptor;
+
+/**
+ * Implements an interceptor that adds protocol trait documentation.
+ *
+ * @param <T> The class of the protocol trait.
+ */
+abstract class ProtocolTraitInterceptor<T extends Trait> implements CodeInterceptor<ProtocolSection, DocWriter> {
+
+    /**
+     * @return returns the class of the protocol trait.
+     */
+    protected abstract Class<T> getTraitClass();
+
+    /**
+     * @return returns the shape id of the protocol trait.
+     */
+    protected abstract ShapeId getTraitId();
+
+    @Override
+    public boolean isIntercepted(ProtocolSection section) {
+        if (section.shape().getMemberTrait(section.context().model(), getTraitClass()).isEmpty()) {
+            return false;
+        }
+        var protocolShape = section.context().model().expectShape(section.protocol());
+        var protocolDefinition = protocolShape.expectTrait(ProtocolDefinitionTrait.class);
+        return protocolDefinition.getTraits().contains(getTraitId());
+    }
+
+    @Override
+    public Class<ProtocolSection> sectionType() {
+        return ProtocolSection.class;
+    }
+
+    @Override
+    public void write(DocWriter writer, String previousText, ProtocolSection section) {
+        var trait = section.shape().getMemberTrait(section.context().model(), getTraitClass()).get();
+        write(writer, previousText, section, trait);
+    }
+
+    abstract void write(DocWriter writer, String previousText, ProtocolSection section, T trait);
+}

smithy-docgen-test/model/main.smithy

@@ -116,6 +116,8 @@ structure DocumentedStructure {
     /// This is a simple string member.
     /// It has documentation that can span multiple lines.
     @since("2023-11-16")
+    @jsonName("foo")
+    @xmlName("bar")
     string: String
 
     /// This member has a pattern trait on it.