fix(codegen): populate dnsSuffix just before consuming hostname (#3170)

Author: trivikr

Diff for: codegen/smithy-aws-typescript-codegen/src/main/java/software/amazon/smithy/aws/typescript/codegen/EndpointGenerator.java

@@ -96,7 +96,10 @@ private void loadServiceEndpoints() {
                         && (config.containsMember("hostname") || config.containsMember("variants"))) {
                     String region = entry.getKey();
                     String hostname = config.getStringMemberOrDefault("hostname", partition.hostnameTemplate);
-                    String resolvedHostname = getResolvedHostname(hostname, dnsSuffix, endpointPrefix, region);
+                    String resolvedHostname = getResolvedHostnameWithDnsSuffix(
+                        getResolvedHostname(hostname, endpointPrefix, region),
+                        dnsSuffix
+                    );
 
                     ArrayNode variants = config.getArrayMember("variants").orElse(ArrayNode.fromNodes());
                     ArrayNode defaultVariant = ArrayNode.fromNodes(getDefaultVariant(resolvedHostname));
@@ -187,15 +190,18 @@ private ObjectNode getDefaultVariant(String hostname) {
             .withMember("tags", ArrayNode.fromStrings(Collections.emptyList()));
     }
 
-    private String getResolvedHostname(String hostnameTemplate, String dnsSuffix, String service) {
-        return getResolvedHostname(hostnameTemplate, dnsSuffix, service, "{region}");
+    private String getResolvedHostname(String hostnameTemplate, String service) {
+        return getResolvedHostname(hostnameTemplate, service, "{region}");
     }
 
-    private String getResolvedHostname(String hostnameTemplate, String dnsSuffix, String service, String region) {
+    private String getResolvedHostname(String hostnameTemplate, String service, String region) {
         return hostnameTemplate
             .replace("{service}", service)
-            .replace("{region}", region)
-            .replace("{dnsSuffix}", dnsSuffix);
+            .replace("{region}", region);
+    }
+
+    private String getResolvedHostnameWithDnsSuffix(String hostnameTemplate, String dnsSuffix) {
+        return hostnameTemplate.replace("{dnsSuffix}", dnsSuffix);
     }
 
     private final class Partition {
@@ -219,7 +225,7 @@ private Partition(ObjectNode config, String partition) {
 
             // Resolve the template to use for this service in this partition.
             String hostname = defaults.expectStringMember("hostname").getValue();
-            hostnameTemplate = getResolvedHostname(hostname, dnsSuffix, endpointPrefix);
+            hostnameTemplate = getResolvedHostname(hostname, endpointPrefix);
 
             ArrayNode mergedVariants = getMergedVariants(
                 partitionDefaults.getArrayMember("variants").orElse(Node.arrayNode()),
@@ -249,12 +255,15 @@ Set<String> getAllRegions() {
         private ArrayNode getVariants(ArrayNode mergedVariants) {
             List<Node> allVariants = new ArrayList<Node>();
 
-            allVariants.add(getDefaultVariant(hostnameTemplate));
+            allVariants.add(getDefaultVariant(getResolvedHostnameWithDnsSuffix(hostnameTemplate, this.dnsSuffix)));
             mergedVariants.forEach(mergedVariant -> {
                 ObjectNode variantNode = mergedVariant.expectObjectNode();
                 String hostname = variantNode.expectStringMember("hostname").getValue();
                 String dnsSuffix = variantNode.getStringMemberOrDefault("dnsSuffix", this.dnsSuffix);
-                String resolvedHostname = getResolvedHostname(hostname, dnsSuffix, endpointPrefix);
+                String resolvedHostname = getResolvedHostnameWithDnsSuffix(
+                    getResolvedHostname(hostname, endpointPrefix),
+                    dnsSuffix
+                );
                 allVariants.add(variantNode.withMember("hostname", resolvedHostname).withoutMember("dnsSuffix"));
             });