From 165e04a7b8956181420b4f10c601d0bbdf97f8cc Mon Sep 17 00:00:00 2001
From: Trivikram Kamat <16024985+trivikr@users.noreply.github.com>
Date: Tue, 27 Aug 2024 15:43:48 -0700
Subject: [PATCH] Process String Array parameters in Endpoints (#1376)

---
 .../endpointsV2/ParameterGenerator.java       |  9 ++++++
 .../endpointsV2/RuleSetParameterFinder.java   | 29 ++++++++++++++++---
 2 files changed, 34 insertions(+), 4 deletions(-)

diff --git a/smithy-typescript-codegen/src/main/java/software/amazon/smithy/typescript/codegen/endpointsV2/ParameterGenerator.java b/smithy-typescript-codegen/src/main/java/software/amazon/smithy/typescript/codegen/endpointsV2/ParameterGenerator.java
index 88cf56867ff..fd02400d491 100644
--- a/smithy-typescript-codegen/src/main/java/software/amazon/smithy/typescript/codegen/endpointsV2/ParameterGenerator.java
+++ b/smithy-typescript-codegen/src/main/java/software/amazon/smithy/typescript/codegen/endpointsV2/ParameterGenerator.java
@@ -18,6 +18,7 @@
 import java.util.AbstractMap;
 import java.util.Map;
 import java.util.Optional;
+import java.util.stream.Collectors;
 import software.amazon.smithy.model.node.BooleanNode;
 import software.amazon.smithy.model.node.Node;
 import software.amazon.smithy.model.node.ObjectNode;
@@ -64,6 +65,9 @@ public ParameterGenerator(String key, Node param, boolean isInputKey) {
                 case "boolean":
                     tsParamType = "boolean";
                     break;
+                case "stringArray":
+                    tsParamType = "string[]";
+                    break;
                 default:
                     // required by linter
             }
@@ -102,6 +106,11 @@ public String defaultAsCodeString() {
             case "boolean":
                 buffer += paramNode.expectBooleanMember("default").getValue() ? "true" : "false";
                 break;
+            case "stringArray":
+                buffer += paramNode.expectArrayMember("default").getElements().stream()
+                    .map(element -> element.expectStringNode().getValue())
+                    .collect(Collectors.joining("`, `", "[`", "`]"));
+                break;
             default:
                 throw new RuntimeException("Unhandled endpoint param type: " + type.getValue());
         }
diff --git a/smithy-typescript-codegen/src/main/java/software/amazon/smithy/typescript/codegen/endpointsV2/RuleSetParameterFinder.java b/smithy-typescript-codegen/src/main/java/software/amazon/smithy/typescript/codegen/endpointsV2/RuleSetParameterFinder.java
index 93d9d4fb3b9..26b00c8cd6d 100644
--- a/smithy-typescript-codegen/src/main/java/software/amazon/smithy/typescript/codegen/endpointsV2/RuleSetParameterFinder.java
+++ b/smithy-typescript-codegen/src/main/java/software/amazon/smithy/typescript/codegen/endpointsV2/RuleSetParameterFinder.java
@@ -18,6 +18,8 @@
 import java.util.HashMap;
 import java.util.Map;
 import java.util.Optional;
+import java.util.stream.Collectors;
+import software.amazon.smithy.model.node.ArrayNode;
 import software.amazon.smithy.model.node.Node;
 import software.amazon.smithy.model.node.NodeVisitor;
 import software.amazon.smithy.model.node.ObjectNode;
@@ -26,6 +28,7 @@
 import software.amazon.smithy.model.shapes.OperationShape;
 import software.amazon.smithy.model.shapes.ServiceShape;
 import software.amazon.smithy.model.shapes.Shape;
+import software.amazon.smithy.model.shapes.ShapeType;
 import software.amazon.smithy.rulesengine.traits.ClientContextParamsTrait;
 import software.amazon.smithy.rulesengine.traits.ContextParamTrait;
 import software.amazon.smithy.rulesengine.traits.EndpointRuleSetTrait;
@@ -66,10 +69,23 @@ public Map<String, String> getClientContextParams() {
         if (trait.isPresent()) {
             ClientContextParamsTrait clientContextParamsTrait = trait.get();
             clientContextParamsTrait.getParameters().forEach((name, definition) -> {
-                map.put(
-                    name,
-                    definition.getType().toString().toLowerCase() // "boolean" and "string" are directly usable in TS.
-                );
+                ShapeType shapeType = definition.getType();
+                if (shapeType.isShapeType(ShapeType.STRING) || shapeType.isShapeType(ShapeType.BOOLEAN)) {
+                    map.put(
+                        name,
+                        // "boolean" and "string" are directly usable in TS.
+                        definition.getType().toString().toLowerCase()
+                    );
+                } else if (shapeType.isShapeType(ShapeType.LIST)) {
+                    map.put(
+                        name,
+                        "string[]" // Only string lists are supported.
+                    );
+                } else {
+                    throw new RuntimeException("unexpected type "
+                        + definition.getType().toString()
+                        + " received as clientContextParam.");
+                }
             });
         }
         return map;
@@ -90,6 +106,11 @@ public Map<String, String> getStaticContextParamValues(OperationShape operation)
                     value = "`" + definition.getValue().expectStringNode().toString() + "`";
                 } else if (definition.getValue().isBooleanNode()) {
                     value = definition.getValue().expectBooleanNode().toString();
+                } else if (definition.getValue().isArrayNode()) {
+                    ArrayNode arrayNode = definition.getValue().expectArrayNode();
+                    value = arrayNode.getElements().stream()
+                      .map(element -> element.expectStringNode().getValue())
+                      .collect(Collectors.joining("`, `", "[`", "`]"));
                 } else {
                     throw new RuntimeException("unexpected type "
                         + definition.getValue().getType().toString()