Improve complex serialization support

This commit adds support for many new complex serializations. This
includes support for HTTP payloads, the prefixHeaders trait, and
nested lists, sets, maps, unions, and structures as well as their
respective HTTP binding location modifications. It also generalizes
the method for generating serde function names across the language.

Author: kstich

smithy-typescript-codegen/src/main/java/software/amazon/smithy/typescript/codegen/CommandGenerator.java

@@ -26,7 +26,6 @@
 import software.amazon.smithy.model.shapes.StructureShape;
 import software.amazon.smithy.typescript.codegen.integration.ProtocolGenerator;
 import software.amazon.smithy.typescript.codegen.integration.RuntimeClientPlugin;
-import software.amazon.smithy.utils.StringUtils;
 
 /**
  * Generates a client command using plugins.
@@ -202,7 +201,7 @@ private void writeSerde() {
                     .write("protocol: string,")
                     .write("context: SerdeContext")
                 .dedent()
-                .openBlock("): $T {", "}", applicationProtocol.getRequestType(), () -> writeSerdeDispatcher("input"));
+                .openBlock("): $T {", "}", applicationProtocol.getRequestType(), () -> writeSerdeDispatcher(true));
 
         writer.write("")
                 .write("private deserialize(")
@@ -211,41 +210,30 @@ private void writeSerde() {
                     .write("protocol: string,")
                     .write("context: SerdeContext")
                 .dedent()
-                .openBlock("): Promise<$L> {", "}", outputType, () -> writeSerdeDispatcher("output"))
+                .openBlock("): Promise<$L> {", "}", outputType, () -> writeSerdeDispatcher(false))
                 .write("");
     }
 
-    private void writeSerdeDispatcher(String inputOrOutput) {
+    private void writeSerdeDispatcher(boolean isInput) {
         writer.openBlock("switch (protocol) {", "}", () -> {
             // Generate case statements for each supported protocol.
             // For example:
             // case 'aws.rest-json-1.1':
             //   return getFooCommandAws_RestJson1_1Serialize(input, utils);
             // TODO Validate this is the right set of protocols; settings.protocols was empty here.
             for (String protocol : settings.resolveServiceProtocols(service)) {
-                String serdeFunctionName = getSerdeFunctionName(symbol, protocol, inputOrOutput);
+                String serdeFunctionName = isInput
+                        ? ProtocolGenerator.getSerFunctionName(symbol, protocol)
+                        : ProtocolGenerator.getDeserFunctionName(symbol, protocol);
                 writer.addImport(serdeFunctionName, serdeFunctionName,
                         "./protocols/" + ProtocolGenerator.getSanitizedName(protocol));
                 writer.write("case '$L':", protocol)
-                        .write("  return $L($L, context);", serdeFunctionName, inputOrOutput);
+                        .write("  return $L($L, context);", serdeFunctionName, isInput ? "input" : "output");
             }
 
             writer.write("default:")
                     .write("  throw new Error(\"Unknown protocol, \" + protocol + \". Expected one of: $L\");",
                            settings.getProtocols());
         });
     }
-
-    private static String getSerdeFunctionName(Symbol commandSymbol, String protocol, String inputOrOutput) {
-        String functionName = StringUtils.uncapitalize(commandSymbol.getName());
-        functionName += ProtocolGenerator.getSanitizedName(protocol);
-
-        if (inputOrOutput.equals("input")) {
-            functionName += "Serialize";
-        } else {
-            functionName += "Deserialize";
-        }
-
-        return functionName;
-    }
 }