Add httpChecksumRequired trait support

Author: JordonPhillips

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

@@ -15,6 +15,7 @@
 import software.amazon.smithy.docgen.core.interceptors.DeprecatedInterceptor;
 import software.amazon.smithy.docgen.core.interceptors.ErrorFaultInterceptor;
 import software.amazon.smithy.docgen.core.interceptors.ExternalDocsInterceptor;
+import software.amazon.smithy.docgen.core.interceptors.HttpChecksumRequiredInterceptor;
 import software.amazon.smithy.docgen.core.interceptors.HttpErrorInterceptor;
 import software.amazon.smithy.docgen.core.interceptors.HttpHeaderInterceptor;
 import software.amazon.smithy.docgen.core.interceptors.HttpInterceptor;
@@ -96,6 +97,7 @@ public List<? extends CodeInterceptor<? extends CodeSection, DocWriter>> interce
                 new XmlAttributeInterceptor(),
                 new XmlNameInterceptor(),
                 new XmlFlattenedInterceptor(),
+                new HttpChecksumRequiredInterceptor(),
                 new HttpResponseCodeInterceptor(),
                 new HttpPayloadInterceptor(),
                 new HttpErrorInterceptor(),

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

@@ -0,0 +1,44 @@
+/*
+ * 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.docgen.core.writers.DocWriter.AdmonitionType;
+import software.amazon.smithy.model.shapes.ShapeId;
+import software.amazon.smithy.model.traits.HttpChecksumRequiredTrait;
+import software.amazon.smithy.utils.Pair;
+import software.amazon.smithy.utils.SmithyInternalApi;
+
+/**
+ * Adds information about query bindings from the
+ * <a href="https://smithy.io/2.0/spec/http-bindings.html#httpquery-trait">
+ * httpQuery trait</a> if the protocol supports it.
+ */
+@SmithyInternalApi
+public final class HttpChecksumRequiredInterceptor extends ProtocolTraitInterceptor<HttpChecksumRequiredTrait> {
+    private static final Pair<String, String> CONTENT_MD5 = Pair.of(
+            "Content-MD5", "https://datatracker.ietf.org/doc/html/rfc1864.html"
+    );
+
+    @Override
+    protected Class<HttpChecksumRequiredTrait> getTraitClass() {
+        return HttpChecksumRequiredTrait.class;
+    }
+
+    @Override
+    protected ShapeId getTraitId() {
+        return HttpChecksumRequiredTrait.ID;
+    }
+
+    @Override
+    void write(DocWriter writer, String previousText, ProtocolSection section, HttpChecksumRequiredTrait trait) {
+        writer.writeWithNoFormatting(previousText + "\n");
+        writer.openAdmonition(AdmonitionType.IMPORTANT);
+        writer.write("This operation REQUIRES a checksum, such as $R.", CONTENT_MD5);
+        writer.closeAdmonition();
+    }
+}