feat: generate unified error dispatcher

.changeset/shy-nails-wonder.md

@@ -0,0 +1,2 @@
+---
+---

smithy-typescript-codegen/src/main/java/software/amazon/smithy/typescript/codegen/integration/HttpBindingProtocolGenerator.java

@@ -517,6 +517,7 @@ public void generateResponseDeserializers(GenerationContext context) {
 
         Set<OperationShape> containedOperations = new TreeSet<>(
                 topDownIndex.getContainedOperations(context.getService()));
+
         for (OperationShape operation : containedOperations) {
             OptionalUtils.ifPresentOrElse(
                     operation.getTrait(HttpTrait.class),
@@ -525,6 +526,18 @@ public void generateResponseDeserializers(GenerationContext context) {
                             "Unable to generate %s protocol response bindings for %s because it does not have an "
                             + "http binding trait", getName(), operation.getId())));
         }
+
+        SymbolReference responseType = getApplicationProtocol().getResponseType();
+        Set<StructureShape> errorShapes = HttpProtocolGeneratorUtils.generateUnifiedErrorDispatcher(
+            context,
+            containedOperations.stream().toList(),
+            responseType,
+            this::writeErrorCodeParser,
+            isErrorCodeInBody,
+            this::getErrorBodyLocation,
+            this::getOperationErrors
+        );
+        deserializingErrorShapes.addAll(errorShapes);
     }
 
     private void generateOperationResponseSerializer(
@@ -2091,7 +2104,7 @@ private void generateOperationResponseDeserializer(
         // e.g., deserializeAws_restJson1_1ExecuteStatement
         String methodName = ProtocolGenerator.getDeserFunctionShortName(symbol);
         String methodLongName = ProtocolGenerator.getDeserFunctionName(symbol, getName());
-        String errorMethodName = methodName + "Error";
+        String errorMethodName = "de_CommandError";
         // Add the normalized output type.
         Symbol outputType = symbol.expectProperty("outputType", Symbol.class);
         String contextType = CodegenUtils.getOperationDeserializerContextType(context.getSettings(), writer,
@@ -2108,7 +2121,7 @@ private void generateOperationResponseDeserializer(
             // status code that's not the modeled code (300 or higher). This allows for
             // returning other 2XX codes that don't match the defined value.
             writer.openBlock("if (output.statusCode !== $L && output.statusCode >= 300) {", "}", trait.getCode(),
-                    () -> writer.write("return $L(output, context);", errorMethodName));
+                    () -> writer.write("return $L(output, context) as any;", errorMethodName));
 
             // Start deserializing the response.
             writer.openBlock("const contents: any = map({", "});", () -> {
@@ -2129,11 +2142,6 @@ private void generateOperationResponseDeserializer(
             writer.write("return contents;");
         });
         writer.write("");
-        // Write out the error deserialization dispatcher.
-        Set<StructureShape> errorShapes = HttpProtocolGeneratorUtils.generateErrorDispatcher(
-                context, operation, responseType, this::writeErrorCodeParser,
-                isErrorCodeInBody, this::getErrorBodyLocation, this::getOperationErrors);
-        deserializingErrorShapes.addAll(errorShapes);
     }
 
     private void generateErrorDeserializer(GenerationContext context, StructureShape error) {

smithy-typescript-codegen/src/main/java/software/amazon/smithy/typescript/codegen/integration/HttpProtocolGeneratorUtils.java

@@ -298,51 +298,49 @@ public static void writeRetryableTrait(TypeScriptWriter writer, StructureShape e
 
     /**
      * Writes a function used to dispatch to the proper error deserializer
-     * for each error that the operation can return. The generated function
+     * for each error that any operation can return. The generated function
      * assumes a deserialization function is generated for the structures
      * returned.
      *
      * @param context The generation context.
-     * @param operation The operation to generate for.
      * @param responseType The response type for the HTTP protocol.
      * @param errorCodeGenerator A consumer
      * @param shouldParseErrorBody Flag indicating whether need to parse response body in this dispatcher function
      * @param bodyErrorLocationModifier A function that returns the location of an error in a body given a data source.
      * @param operationErrorsToShapes A map of error names to their {@link ShapeId}.
      * @return A set of all error structure shapes for the operation that were dispatched to.
      */
-    static Set<StructureShape> generateErrorDispatcher(
-            GenerationContext context,
-            OperationShape operation,
-            SymbolReference responseType,
-            Consumer<GenerationContext> errorCodeGenerator,
-            boolean shouldParseErrorBody,
-            BiFunction<GenerationContext, String, String> bodyErrorLocationModifier,
-            BiFunction<GenerationContext, OperationShape, Map<String, ShapeId>> operationErrorsToShapes
+    static Set<StructureShape> generateUnifiedErrorDispatcher(
+        GenerationContext context,
+        List<OperationShape> operations,
+        SymbolReference responseType,
+        Consumer<GenerationContext> errorCodeGenerator,
+        boolean shouldParseErrorBody,
+        BiFunction<GenerationContext, String, String> bodyErrorLocationModifier,
+        BiFunction<GenerationContext, List<OperationShape>, Map<String, ShapeId>> operationErrorsToShapes
     ) {
         TypeScriptWriter writer = context.getWriter();
         SymbolProvider symbolProvider = context.getSymbolProvider();
         Set<StructureShape> errorShapes = new TreeSet<>();
 
-        Symbol symbol = symbolProvider.toSymbol(operation);
-        Symbol outputType = symbol.expectProperty("outputType", Symbol.class);
-        String errorMethodName = ProtocolGenerator.getDeserFunctionShortName(symbol) + "Error";
-        String errorMethodLongName = ProtocolGenerator.getDeserFunctionName(symbol, context.getProtocolName())
-                + "Error";
+        String errorMethodName = "de_CommandError";
+        String errorMethodLongName = "deserialize_"
+            + ProtocolGenerator.getSanitizedName(context.getProtocolName())
+            + "CommandError";
 
         writer.writeDocs(errorMethodLongName);
-                writer.openBlock("const $L = async(\n"
-                               + "  output: $T,\n"
-                               + "  context: __SerdeContext,\n"
-                               + "): Promise<$T> => {", "}", errorMethodName, responseType, outputType, () -> {
+        writer.openBlock("const $L = async(\n"
+            + "  output: $T,\n"
+            + "  context: __SerdeContext,\n"
+            + "): Promise<unknown> => {", "}", errorMethodName, responseType, () -> {
             // Prepare error response for parsing error code. If error code needs to be parsed from response body
             // then we collect body and parse it to JS object, otherwise leave the response body as is.
             if (shouldParseErrorBody) {
                 writer.openBlock("const parsedOutput: any = {", "};",
-                        () -> {
-                            writer.write("...output,");
-                            writer.write("body: await parseErrorBody(output.body, context)");
-                        });
+                    () -> {
+                        writer.write("...output,");
+                        writer.write("body: await parseErrorBody(output.body, context)");
+                    });
             }
 
             // Error responses must be at least BaseException interface
@@ -370,7 +368,8 @@ static Set<StructureShape> generateErrorDispatcher(
                 });
             };
 
-            Map<String, ShapeId> operationNamesToShapes = operationErrorsToShapes.apply(context, operation);
+            Map<String, ShapeId> operationNamesToShapes = operationErrorsToShapes.apply(context, operations);
+
             if (!operationNamesToShapes.isEmpty()) {
                 writer.openBlock("switch (errorCode) {", "}", () -> {
                     // Generate the case statement for each error, invoking the specific deserializer.

smithy-typescript-codegen/src/main/java/software/amazon/smithy/typescript/codegen/integration/HttpRpcProtocolGenerator.java

@@ -224,6 +224,18 @@ public void generateResponseDeserializers(GenerationContext context) {
         for (OperationShape operation : containedOperations) {
             generateOperationDeserializer(context, operation);
         }
+
+        SymbolReference responseType = getApplicationProtocol().getResponseType();
+        Set<StructureShape> errorShapes = HttpProtocolGeneratorUtils.generateUnifiedErrorDispatcher(
+            context,
+            containedOperations.stream().toList(),
+            responseType,
+            this::writeErrorCodeParser,
+            isErrorCodeInBody,
+            this::getErrorBodyLocation,
+            this::getOperationErrors
+        );
+        deserializingErrorShapes.addAll(errorShapes);
     }
 
     private void generateOperationSerializer(GenerationContext context, OperationShape operation) {
@@ -435,7 +447,7 @@ private void generateOperationDeserializer(GenerationContext context, OperationS
         // e.g., deserializeAws_restJson1_1ExecuteStatement
         String methodName = ProtocolGenerator.getDeserFunctionShortName(symbol);
         String methodLongName = ProtocolGenerator.getDeserFunctionName(symbol, getName());
-        String errorMethodName = methodName + "Error";
+        String errorMethodName = "de_CommandError";
         String serdeContextType = CodegenUtils.getOperationDeserializerContextType(context.getSettings(), writer,
                 context.getModel(), operation);
         // Add the normalized output type.
@@ -449,7 +461,7 @@ private void generateOperationDeserializer(GenerationContext context, OperationS
                        + "): Promise<$T> => {", "}", methodName, responseType, serdeContextType, outputType, () -> {
             // Redirect error deserialization to the dispatcher
             writer.openBlock("if (output.statusCode >= 300) {", "}", () -> {
-                writer.write("return $L(output, context);", errorMethodName);
+                writer.write("return $L(output, context) as any;", errorMethodName);
             });
 
             // Start deserializing the response.
@@ -465,12 +477,6 @@ private void generateOperationDeserializer(GenerationContext context, OperationS
             writer.write("return response;");
         });
         writer.write("");
-
-        // Write out the error deserialization dispatcher.
-        Set<StructureShape> errorShapes = HttpProtocolGeneratorUtils.generateErrorDispatcher(
-                context, operation, responseType, this::writeErrorCodeParser,
-                isErrorCodeInBody, this::getErrorBodyLocation, this::getOperationErrors);
-        deserializingErrorShapes.addAll(errorShapes);
     }
 
     private void generateErrorDeserializer(GenerationContext context, StructureShape error) {

smithy-typescript-codegen/src/main/java/software/amazon/smithy/typescript/codegen/integration/ProtocolGenerator.java

@@ -16,6 +16,7 @@
 package software.amazon.smithy.typescript.codegen.integration;
 
 import java.util.Collection;
+import java.util.LinkedHashMap;
 import java.util.Map;
 import java.util.stream.Collectors;
 import software.amazon.smithy.codegen.core.CodegenException;
@@ -303,6 +304,23 @@ default Map<String, ShapeId> getOperationErrors(GenerationContext context, Opera
         return HttpProtocolGeneratorUtils.getOperationErrors(context, operation);
     }
 
+    /**
+     * Returns a map of error names to their {@link ShapeId}.
+     *
+     * @param context the generation context
+     * @param operations the operation shapes to retrieve errors for
+     * @return map of error names to {@link ShapeId}
+     */
+    default Map<String, ShapeId> getOperationErrors(GenerationContext context, Collection<OperationShape> operations) {
+        Map<String, ShapeId> errors = new LinkedHashMap<>();
+        for (OperationShape operation : operations) {
+            errors.putAll(
+                getOperationErrors(context, operation)
+            );
+        }
+        return errors;
+    }
+
     /**
      * Context object used for service serialization and deserialization.
      */