Normalize map keys for shapes targeted by httpPrefixHeaders during deserialization

codegen/smithy-go-codegen/src/main/java/software/amazon/smithy/go/codegen/GoWriter.java

@@ -19,6 +19,7 @@
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.List;
+import java.util.Optional;
 import java.util.StringJoiner;
 import java.util.function.BiFunction;
 import java.util.logging.Logger;
@@ -28,10 +29,13 @@
 import software.amazon.smithy.codegen.core.SymbolDependency;
 import software.amazon.smithy.codegen.core.SymbolDependencyContainer;
 import software.amazon.smithy.codegen.core.SymbolReference;
+import software.amazon.smithy.go.codegen.knowledge.GoUsageIndex;
 import software.amazon.smithy.model.Model;
 import software.amazon.smithy.model.shapes.MemberShape;
 import software.amazon.smithy.model.shapes.Shape;
+import software.amazon.smithy.model.traits.DeprecatedTrait;
 import software.amazon.smithy.model.traits.DocumentationTrait;
+import software.amazon.smithy.model.traits.HttpPrefixHeadersTrait;
 import software.amazon.smithy.model.traits.MediaTypeTrait;
 import software.amazon.smithy.model.traits.RequiredTrait;
 import software.amazon.smithy.model.traits.StringTrait;
@@ -290,24 +294,60 @@ boolean writePackageShapeDocs(Shape shape) {
      * @return Returns true if docs were written.
      */
     boolean writeMemberDocs(Model model, MemberShape member) {
-        return member.getMemberTrait(model, DocumentationTrait.class)
+        boolean hasDocs;
+
+        hasDocs = member.getMemberTrait(model, DocumentationTrait.class)
                 .map(DocumentationTrait::getValue)
                 .map(docs -> {
                     writeDocs(docs);
-                    member.getMemberTrait(model, MediaTypeTrait.class)
-                            .map(StringTrait::getValue)
-                            .ifPresent(mediaType -> writeDocs(
-                                    "\n\nThis value conforms to the media type: " + mediaType));
-
-                    member.getMemberTrait(model, RequiredTrait.class)
-                            .ifPresent((value) -> {
-                                if (docs.length() != 0) {
-                                    writeDocs("");
-                                }
-                                writeDocs("This member is required.");
-                            });
                     return true;
                 }).orElse(false);
+
+        Optional<String> stringOptional = member.getMemberTrait(model, MediaTypeTrait.class)
+                .map(StringTrait::getValue);
+        if (stringOptional.isPresent()) {
+            if (hasDocs) {
+                writeDocs("");
+            }
+            writeDocs("This value conforms to the media type: " + stringOptional.get());
+            hasDocs = true;
+        }
+
+        GoUsageIndex usageIndex = GoUsageIndex.of(model);
+        if (usageIndex.isUsedForOutput(member)) {
+            if (member.getMemberTrait(model,
+                    HttpPrefixHeadersTrait.class).isPresent()) {
+                if (hasDocs) {
+                    writeDocs("");
+                }
+                writeDocs("Map keys will be normalized to lower-case.");
+                hasDocs = true;
+            }
+        }
+
+        if (member.getMemberTrait(model, RequiredTrait.class).isPresent()) {
+            if (hasDocs) {
+                writeDocs("");
+            }
+            writeDocs("This member is required.");
+            hasDocs = true;
+        }
+
+        Optional<DeprecatedTrait> deprecatedTrait = member.getMemberTrait(model, DeprecatedTrait.class);
+        if (deprecatedTrait.isPresent()) {
+            if (hasDocs) {
+                writeDocs("");
+            }
+            final String defaultMessage = "This member has been deprecated.";
+            writeDocs("Deprecated: " + deprecatedTrait.get().getMessage().map(s -> {
+                if (s.length() == 0) {
+                    return defaultMessage;
+                }
+                return s;
+            }).orElse(defaultMessage));
+        }
+
+        return hasDocs;
     }
 
     @Override

codegen/smithy-go-codegen/src/main/java/software/amazon/smithy/go/codegen/OperationGenerator.java

@@ -29,6 +29,7 @@
 import software.amazon.smithy.model.shapes.OperationShape;
 import software.amazon.smithy.model.shapes.ServiceShape;
 import software.amazon.smithy.model.shapes.StructureShape;
+import software.amazon.smithy.model.traits.DeprecatedTrait;
 
 /**
  * Generates a client operation and associated custom shapes.
@@ -91,7 +92,20 @@ public void run() {
         Symbol outputSymbol = symbolProvider.toSymbol(outputShape);
 
         // Generate operation method
-        writer.writeShapeDocs(operation);
+        final boolean hasDocs = writer.writeShapeDocs(operation);
+        operation.getTrait(DeprecatedTrait.class)
+                .ifPresent(trait -> {
+                    if (hasDocs) {
+                        writer.writeDocs("");
+                    }
+                    final String defaultMessage = "This operation has been deprecated.";
+                    writer.writeDocs("Deprecated: " + trait.getMessage().map(s -> {
+                        if (s.length() == 0) {
+                            return defaultMessage;
+                        }
+                        return s;
+                    }).orElse(defaultMessage));
+                });
         Symbol contextSymbol = SymbolUtils.createValueSymbolBuilder("Context", SmithyGoDependency.CONTEXT).build();
         writer.openBlock("func (c $P) $T(ctx $T, params $P, optFns ...func(*Options)) ($P, error) {", "}",
                 serviceSymbol, operationSymbol, contextSymbol, inputSymbol, outputSymbol, () -> {

codegen/smithy-go-codegen/src/main/java/software/amazon/smithy/go/codegen/ShapeValueGenerator.java

@@ -17,7 +17,9 @@
 
 package software.amazon.smithy.go.codegen;
 
+import java.util.List;
 import java.util.Map;
+import java.util.Optional;
 import java.util.logging.Logger;
 import software.amazon.smithy.codegen.core.CodegenException;
 import software.amazon.smithy.codegen.core.Symbol;
@@ -32,24 +34,31 @@
 import software.amazon.smithy.model.node.NumberNode;
 import software.amazon.smithy.model.node.ObjectNode;
 import software.amazon.smithy.model.node.StringNode;
+import software.amazon.smithy.model.shapes.MapShape;
 import software.amazon.smithy.model.shapes.MemberShape;
 import software.amazon.smithy.model.shapes.Shape;
 import software.amazon.smithy.model.shapes.ShapeType;
 import software.amazon.smithy.model.shapes.SimpleShape;
 import software.amazon.smithy.model.shapes.StructureShape;
 import software.amazon.smithy.model.shapes.UnionShape;
 import software.amazon.smithy.model.traits.EnumTrait;
+import software.amazon.smithy.model.traits.HttpPrefixHeadersTrait;
 import software.amazon.smithy.model.traits.StreamingTrait;
+import software.amazon.smithy.model.traits.Trait;
+import software.amazon.smithy.utils.ListUtils;
+import software.amazon.smithy.utils.OptionalUtils;
+import software.amazon.smithy.utils.SmithyBuilder;
 
 /**
  * Generates a shape type declaration based on the parameters provided.
  */
 public final class ShapeValueGenerator {
     private static final Logger LOGGER = Logger.getLogger(ShapeValueGenerator.class.getName());
 
-    protected final Model model;
-    protected final SymbolProvider symbolProvider;
-    protected final GoPointableIndex pointableIndex;
+    private final Model model;
+    private final SymbolProvider symbolProvider;
+    private final GoPointableIndex pointableIndex;
+    private final Config config;
 
     /**
      * Initializes a shape value generator.
@@ -58,9 +67,21 @@ public final class ShapeValueGenerator {
      * @param symbolProvider the symbol provider.
      */
     public ShapeValueGenerator(Model model, SymbolProvider symbolProvider) {
+        this(model, symbolProvider, Config.builder().build());
+    }
+
+    /**
+     * Initializes a shape value generator.
+     *
+     * @param model          the Smithy model references.
+     * @param symbolProvider the symbol provider.
+     * @param config         the shape value generator config.
+     */
+    public ShapeValueGenerator(Model model, SymbolProvider symbolProvider, Config config) {
         this.model = model;
         this.symbolProvider = symbolProvider;
         this.pointableIndex = GoPointableIndex.of(model);
+        this.config = config;
     }
 
     /**
@@ -79,7 +100,8 @@ public void writePointableStructureShapeValueInline(GoWriter writer, StructureSh
         // not within the context of a member shape reference.
         Symbol symbol = symbolProvider.toSymbol(shape);
         writer.write("&$T{", symbol);
-        params.accept(new ShapeValueNodeVisitor(writer, this, shape));
+        params.accept(new ShapeValueNodeVisitor(writer, this, shape, ListUtils.copyOf(shape.getAllTraits().values()),
+                config));
         writer.writeInline("}");
     }
 
@@ -149,7 +171,8 @@ protected void structDeclShapeValue(GoWriter writer, MemberShape member, Node pa
 
         String addr = CodegenUtils.asAddressIfAddressable(model, pointableIndex, member, "");
         writer.write("$L$T{", addr, symbol);
-        params.accept(new ShapeValueNodeVisitor(writer, this, model.expectShape(member.getTarget())));
+        params.accept(new ShapeValueNodeVisitor(writer, this, model.expectShape(member.getTarget()),
+                ListUtils.copyOf(member.getAllTraits().values()), config));
         writer.writeInline("}");
     }
 
@@ -197,7 +220,8 @@ protected void unionDeclShapeValue(GoWriter writer, MemberShape member, ObjectNo
      */
     protected void listDeclShapeValue(GoWriter writer, MemberShape member, Node params) {
         writer.write("$P{", symbolProvider.toSymbol(member));
-        params.accept(new ShapeValueNodeVisitor(writer, this, model.expectShape(member.getTarget())));
+        params.accept(new ShapeValueNodeVisitor(writer, this, model.expectShape(member.getTarget()),
+                ListUtils.copyOf(member.getAllTraits().values()), config));
         writer.writeInline("}");
     }
 
@@ -210,7 +234,8 @@ protected void listDeclShapeValue(GoWriter writer, MemberShape member, Node para
      */
     protected void mapDeclShapeValue(GoWriter writer, MemberShape member, Node params) {
         writer.write("$P{", symbolProvider.toSymbol(member));
-        params.accept(new ShapeValueNodeVisitor(writer, this, model.expectShape(member.getTarget())));
+        params.accept(new ShapeValueNodeVisitor(writer, this, model.expectShape(member.getTarget()),
+                ListUtils.copyOf(member.getAllTraits().values()), config));
         writer.writeInline("}");
     }
 
@@ -327,17 +352,58 @@ protected void writeScalarValueInline(GoWriter writer, MemberShape member, Node
                 break;
         }
 
-        params.accept(new ShapeValueNodeVisitor(writer, this, target));
+        params.accept(new ShapeValueNodeVisitor(writer, this, target,
+                ListUtils.copyOf(member.getAllTraits().values()), config));
         writer.writeInline(closing);
     }
 
+    /**
+     * Configuration that determines how shapes values are generated.
+     */
+    public static final class Config {
+        private final boolean normalizeHttpPrefixHeaderKeys;
+
+        private Config(Builder builder) {
+            normalizeHttpPrefixHeaderKeys = builder.normalizeHttpPrefixHeaderKeys;
+        }
+
+        public static Builder builder() {
+            return new Builder();
+        }
+
+        /**
+         * Returns whether maps with the httpPrefixHeader trait should have their keys normalized.
+         *
+         * @return whether to normalize http prefix header keys
+         */
+        public boolean isNormalizeHttpPrefixHeaderKeys() {
+            return normalizeHttpPrefixHeaderKeys;
+        }
+
+        public static final class Builder implements SmithyBuilder<Config> {
+            private boolean normalizeHttpPrefixHeaderKeys;
+
+            public Builder normalizeHttpPrefixHeaderKeys(boolean normalizeHttpPrefixHeaderKeys) {
+                this.normalizeHttpPrefixHeaderKeys = normalizeHttpPrefixHeaderKeys;
+                return this;
+            }
+
+            @Override
+            public Config build() {
+                return new Config(this);
+            }
+        }
+    }
+
     /**
      * NodeVisitor to walk shape value declarations with node values.
      */
     private final class ShapeValueNodeVisitor implements NodeVisitor<Void> {
-        GoWriter writer;
-        ShapeValueGenerator valueGen;
-        Shape currentShape;
+        private final GoWriter writer;
+        private final ShapeValueGenerator valueGen;
+        private final Shape currentShape;
+        private final List<Trait> traits;
+        private final Config config;
 
         /**
          * Initializes shape value visitor.
@@ -347,9 +413,42 @@ private final class ShapeValueNodeVisitor implements NodeVisitor<Void> {
          * @param shape    the shape that visiting is relative to.
          */
         private ShapeValueNodeVisitor(GoWriter writer, ShapeValueGenerator valueGen, Shape shape) {
+            this(writer, valueGen, shape, ListUtils.of());
+        }
+
+        /**
+         * Initializes shape value visitor.
+         *
+         * @param writer   writer to write generated code with.
+         * @param valueGen shape value generator.
+         * @param shape    the shape that visiting is relative to.
+         * @param traits   the traits applied to the target shape by a MemberShape.
+         */
+        private ShapeValueNodeVisitor(GoWriter writer, ShapeValueGenerator valueGen, Shape shape, List<Trait> traits) {
+            this(writer, valueGen, shape, traits, Config.builder().build());
+        }
+
+        /**
+         * Initializes shape value visitor.
+         *
+         * @param writer   writer to write generated code with.
+         * @param valueGen shape value generator.
+         * @param shape    the shape that visiting is relative to.
+         * @param traits   the traits applied to the target shape by a MemberShape.
+         * @param config   the shape value generator config.
+         */
+        private ShapeValueNodeVisitor(
+                GoWriter writer,
+                ShapeValueGenerator valueGen,
+                Shape shape,
+                List<Trait> traits,
+                Config config
+        ) {
             this.writer = writer;
             this.valueGen = valueGen;
             this.currentShape = shape;
+            this.traits = traits;
+            this.config = config;
         }
 
         /**
@@ -395,10 +494,18 @@ public Void objectNode(ObjectNode node) {
                         break;
 
                     case MAP:
-                        member = this.currentShape.asMapShape().get().getValue();
+                        MapShape mapShape = this.currentShape.asMapShape().get();
+
+                        String keyValue = keyNode.getValue();
+                        if (config.isNormalizeHttpPrefixHeaderKeys()) {
+                            keyValue = OptionalUtils.or(getTrait(HttpPrefixHeadersTrait.class),
+                                    () -> mapShape.getTrait(HttpPrefixHeadersTrait.class))
+                                    .map(httpPrefixHeadersTrait -> keyNode.getValue().toLowerCase())
+                                    .orElse(keyValue);
+                        }
 
-                        writer.write("$S: ", keyNode.getValue());
-                        valueGen.writeMemberValueInline(writer, member, valueNode);
+                        writer.write("$S: ", keyValue);
+                        valueGen.writeMemberValueInline(writer, mapShape.getValue(), valueNode);
                         writer.write(",");
                         break;
 
@@ -523,6 +630,15 @@ private void writeInlineBigIntegerInit(GoWriter writer, Object value) {
                             + "}()",
                     value, value);
         }
+
+        private <T extends Trait> Optional<T> getTrait(Class<T> traitClass) {
+            for (Trait trait : traits) {
+                if (traitClass.isInstance(trait)) {
+                    return Optional.of((T) trait);
+                }
+            }
+            return Optional.empty();
+        }
     }
 
 }