Kotlin: make cuttable keys configurable via Catalog and update StreamingParser to use dynamic values

Author: nan-yu

agent_sdks/kotlin/src/main/kotlin/com/google/a2ui/parser/StreamingParser.kt

@@ -43,7 +43,8 @@ abstract class StreamingParser(
     catalog?.let { TopologyAnalyzer.extractComponentRefFields(it) } ?: emptyMap()
   protected val requiredFieldsMap: Map<String, Set<String>> =
     catalog?.let { TopologyAnalyzer.extractComponentRequiredFields(it) } ?: emptyMap()
-  protected val validator: A2uiValidator? = catalog?.let { A2uiValidator(it, schemaMappings) }
+  protected val cuttableKeys: Set<String> = catalog?.cuttableKeys ?: emptySet()
+  internal var validator: A2uiValidator? = catalog?.let { A2uiValidator(it, schemaMappings) }
 
   protected var foundDelimiter = false
   protected val buffer = StringBuilder()
@@ -186,7 +187,7 @@ abstract class StreamingParser(
         val keyMatch = KEY_MATCH_REGEX.find(prefix)
         if (keyMatch != null) {
           val key = keyMatch.groupValues[1]
-          if (key !in CUTTABLE_KEYS) {
+          if (key !in cuttableKeys) {
             return ""
           }
 
@@ -262,9 +263,10 @@ abstract class StreamingParser(
         continue
       }
 
-      if (validator != null) {
+      val currentValidator = validator
+      if (currentValidator != null) {
         try {
-          validator.validate(m, strictIntegrity = strictIntegrity)
+          currentValidator.validate(m, strictIntegrity = strictIntegrity)
         } catch (e: Exception) {
           if (strictIntegrity) {
             throw e
@@ -1087,9 +1089,6 @@ abstract class StreamingParser(
   }
 
   companion object {
-    internal val CUTTABLE_KEYS =
-      setOf("literalString", "valueString", "label", "hint", "caption", "altText", "text")
-
     @JvmStatic internal val logger: Logger = Logger.getLogger(StreamingParser::class.java.name)
 
     private val KEY_MATCH_REGEX = Regex("\"([^\"]+)\"\\s*:\\s*$")

agent_sdks/kotlin/src/main/kotlin/com/google/a2ui/parser/StreamingParserV08.kt

@@ -78,9 +78,7 @@ class StreamingParserV08(
     sid: String?,
     messages: MutableList<ResponsePart>,
   ): Boolean {
-    if (validator != null) {
-      validator.validate(obj, strictIntegrity = false)
-    }
+    validator?.validate(obj, strictIntegrity = false)
 
     var currentSid = obj["surfaceId"]?.jsonPrimitive?.content ?: surfaceId
     when {

agent_sdks/kotlin/src/main/kotlin/com/google/a2ui/parser/StreamingParserV09.kt

@@ -69,9 +69,7 @@ class StreamingParserV09(
     sid: String?,
     messages: MutableList<ResponsePart>,
   ): Boolean {
-    if (validator != null) {
-      validator.validate(obj, strictIntegrity = false)
-    }
+    validator?.validate(obj, strictIntegrity = false)
 
     var currentSid = obj["surfaceId"]?.jsonPrimitive?.content ?: surfaceId
     when {

agent_sdks/kotlin/src/main/kotlin/com/google/a2ui/schema/A2uiConstants.kt

@@ -26,6 +26,10 @@ object A2uiConstants {
   const val CATALOG_ID_KEY = "catalogId"
   const val CATALOG_STYLES_KEY = "styles"
 
+  @JvmField
+  val DEFAULT_CUTTABLE_KEYS =
+    setOf("literalString", "valueString", "label", "hint", "caption", "altText", "text")
+
   // Protocol constants
   const val SUPPORTED_CATALOG_IDS_KEY = "supportedCatalogIds"
   const val INLINE_CATALOGS_KEY = "inlineCatalogs"

agent_sdks/kotlin/src/main/kotlin/com/google/a2ui/schema/Catalog.kt

@@ -41,12 +41,18 @@ data class CatalogConfig(
   @JvmField val name: String,
   @JvmField val provider: A2uiCatalogProvider,
   @JvmField val examplesPath: String? = null,
+  @JvmField val customCuttableKeys: Set<String>? = null,
 ) {
   companion object {
     /** Create a [CatalogConfig] using a [FileSystemCatalogProvider]. */
     @JvmStatic
     @JvmOverloads
-    fun fromPath(name: String, catalogPath: String, examplesPath: String? = null): CatalogConfig {
+    fun fromPath(
+      name: String,
+      catalogPath: String,
+      examplesPath: String? = null,
+      customCuttableKeys: Set<String>? = null,
+    ): CatalogConfig {
       val uri =
         try {
           URI(catalogPath)
@@ -66,7 +72,7 @@ data class CatalogConfig(
           else -> throw IllegalArgumentException("Unsupported catalog URL scheme: $catalogPath")
         }
 
-      return CatalogConfig(name, provider, resolveExamplesPath(examplesPath))
+      return CatalogConfig(name, provider, resolveExamplesPath(examplesPath), customCuttableKeys)
     }
   }
 }
@@ -95,12 +101,16 @@ data class A2uiCatalog(
   @JvmField val serverToClientSchema: JsonObject,
   @JvmField val commonTypesSchema: JsonObject,
   @JvmField val catalogSchema: JsonObject,
+  @JvmField val customCuttableKeys: Set<String>? = null,
 ) {
 
   companion object {
     private val logger = Logger.getLogger(A2uiCatalog::class.java.name)
   }
 
+  val cuttableKeys: Set<String>
+    get() = customCuttableKeys ?: A2uiConstants.DEFAULT_CUTTABLE_KEYS
+
   val validator: A2uiValidator by lazy { A2uiValidator(this) }
 
   val catalogId: String

agent_sdks/kotlin/src/test/kotlin/com/google/a2ui/conformance/ConformanceTest.kt

@@ -172,14 +172,28 @@ class ConformanceTest {
         else -> JsonObject(emptyMap())
       }
 
+    val customCuttableKeys =
+      (catalogMap["custom_cuttable_keys"] as? List<*>)?.mapNotNull { it as? String }?.toSet()
+
     val catalog =
-      A2uiCatalog(
-        version = version,
-        name = TEST_CATALOG_NAME,
-        serverToClientSchema = s2cSchema,
-        commonTypesSchema = commonTypesSchema,
-        catalogSchema = catalogSchema,
-      )
+      if (customCuttableKeys != null) {
+        A2uiCatalog(
+          version = version,
+          name = TEST_CATALOG_NAME,
+          serverToClientSchema = s2cSchema,
+          commonTypesSchema = commonTypesSchema,
+          catalogSchema = catalogSchema,
+          customCuttableKeys = customCuttableKeys,
+        )
+      } else {
+        A2uiCatalog(
+          version = version,
+          name = TEST_CATALOG_NAME,
+          serverToClientSchema = s2cSchema,
+          commonTypesSchema = commonTypesSchema,
+          catalogSchema = catalogSchema,
+        )
+      }
 
     return Pair(catalog, schemaMappings)
   }
@@ -305,6 +319,11 @@ class ConformanceTest {
             val expectOutput = case["expect_output"] as String
             assertEquals(expectOutput.trim(), output.trim())
           }
+          "verify_cuttable_keys" -> {
+            val expect = case[ConformanceTestHelper.KEY_EXPECT] as Map<*, *>
+            val expectCuttableKeys = expect["custom_cuttable_keys"] as List<String>
+            assertEquals(expectCuttableKeys.toSet(), catalog!!.cuttableKeys)
+          }
           else -> assert(false, { "Unknown action: $action" })
         }
       }
@@ -583,6 +602,9 @@ class ConformanceTest {
           catalogMap?.let { buildCatalog(it, conformanceDir, baseSchemaMappings) }
             ?: (null to emptyMap())
         val parser = StreamingParser.create(catalog, schemaMappings)
+        if (case["disable_validation"] as? Boolean == true) {
+          parser.validator = null
+        }
 
         for ((stepIdx, stepObj) in steps.withIndex()) {
           val step = stepObj as Map<*, *>