Add Gradle Task to Parse V2 supported-configurations.json Format

buildSrc/src/main/kotlin/datadog/gradle/plugin/config/ParseV2SupportedConfigurationsTask.kt

@@ -0,0 +1,214 @@
+package datadog.gradle.plugin.config
+
+import org.gradle.api.DefaultTask
+import org.gradle.api.model.ObjectFactory
+import org.gradle.api.tasks.Input
+import org.gradle.api.tasks.InputFile
+import org.gradle.api.tasks.OutputDirectory
+import org.gradle.api.tasks.TaskAction
+import com.fasterxml.jackson.core.type.TypeReference
+import com.fasterxml.jackson.databind.ObjectMapper
+import org.gradle.api.tasks.CacheableTask
+import org.gradle.api.tasks.PathSensitive
+import org.gradle.api.tasks.PathSensitivity
+import java.io.File
+import java.io.FileInputStream
+import java.io.PrintWriter
+import javax.inject.Inject
+
+@CacheableTask
+abstract class ParseV2SupportedConfigurationsTask  @Inject constructor(
+  private val objects: ObjectFactory
+) : DefaultTask() {
+  @InputFile
+  @PathSensitive(PathSensitivity.NONE)
+  val jsonFile = objects.fileProperty()
+
+  @get:OutputDirectory
+  val destinationDirectory = objects.directoryProperty()
+
+  @Input
+  val className = objects.property(String::class.java)
+
+  @TaskAction
+  fun generate() {
+    val input = jsonFile.get().asFile
+    val outputDir = destinationDirectory.get().asFile
+    val finalClassName = className.get()
+    outputDir.mkdirs()
+
+    // Read JSON (directly from the file, not classpath)
+    val mapper = ObjectMapper()
+    val fileData: Map<String, Any?> = FileInputStream(input).use { inStream ->
+      mapper.readValue(inStream, object : TypeReference<Map<String, Any?>>() {})
+    }
+
+    // Fetch top-level keys of JSON file
+    @Suppress("UNCHECKED_CAST")
+    val supportedRaw = fileData["supportedConfigurations"] as Map<String, List<Map<String, Any?>>>
+    @Suppress("UNCHECKED_CAST")
+    val deprecated = (fileData["deprecations"] as? Map<String, String>) ?: emptyMap()
+
+    // Parse supportedConfigurations key to into a V2 format
+    val supported: Map<String, List<SupportedConfiguration>> = supportedRaw.mapValues { (_, configList) ->
+      configList.map { configMap ->
+        SupportedConfiguration(
+          configMap["version"] as? String,
+          configMap["type"] as? String,
+          configMap["default"] as? String,
+          (configMap["aliases"] as? List<String>) ?: emptyList(),
+          (configMap["propertyKeys"] as? List<String>) ?: emptyList()
+        )
+      }
+    }
+
+    // Generate top-level mapping from config -> list of aliases and reverse alias mapping from alias -> top-level config
+    // Note: This top-level alias mapping will be deprecated once Config Registry is mature enough to understand which version of a config a customer is using
+    val aliases: Map<String, List<String>> = supported.mapValues { (_, configList) ->
+      configList.flatMap { it.aliases }.distinct()
+    }
+
+    val aliasMapping = mutableMapOf<String, String>()
+    for ((canonical, alist) in aliases) {
+      for (alias in alist) aliasMapping[alias] = canonical
+    }
+
+    val reversePropertyKeysMap: Map<String, String> = supported.flatMap { (canonical, configList) ->
+      configList.flatMap { config ->
+        config.propertyKeys.map { propertyKey -> propertyKey to canonical }
+      }
+    }.toMap()
+
+    // Build the output .java path from the fully-qualified class name
+    val pkgName = finalClassName.substringBeforeLast('.', "")
+    val pkgPath = pkgName.replace('.', File.separatorChar)
+    val simpleName = finalClassName.substringAfterLast('.')
+    val pkgDir = if (pkgPath.isEmpty()) outputDir else File(outputDir, pkgPath).also { it.mkdirs() }
+    val generatedFile = File(pkgDir, "$simpleName.java").absolutePath
+
+    // Call your existing generator (same signature as in your Java code)
+    generateJavaFile(
+      generatedFile,
+      simpleName,
+      pkgName,
+      supported,
+      aliases,
+      aliasMapping,
+      deprecated,
+      reversePropertyKeysMap
+    )
+  }
+
+  private fun generateJavaFile(
+    outputPath: String,
+    className: String,
+    packageName: String,
+    supported: Map<String, List<SupportedConfiguration>>,
+    aliases: Map<String, List<String>>,
+    aliasMapping: Map<String, String>,
+    deprecated: Map<String, String>,
+    reversePropertyKeysMap: Map<String, String>
+  ) {
+    val outFile = File(outputPath)
+    outFile.parentFile?.mkdirs()
+
+    PrintWriter(outFile).use { out ->
+      out.println("package $packageName;")
+      out.println()
+      out.println("import java.util.*;")
+      out.println()
+      out.println("public final class $className {")
+      out.println()
+      out.println("  public static final Map<String, List<SupportedConfiguration>> SUPPORTED;")
+      out.println()
+      out.println("  public static final Map<String, List<String>> ALIASES;")
+      out.println()
+      out.println("  public static final Map<String, String> ALIAS_MAPPING;")
+      out.println()
+      out.println("  public static final Map<String, String> DEPRECATED;")
+      out.println()
+      out.println("  public static final Map<String, String> REVERSE_PROPERTY_KEYS_MAP;")
+      out.println()
+      out.println("  static {")
+      out.println()
+
+      // SUPPORTED
+      out.println("    Map<String, List<SupportedConfiguration>> supportedMap = new HashMap<>();")
+      for ((key, configList) in supported.toSortedMap()) {
+        out.print("    supportedMap.put(\"${esc(key)}\", Collections.unmodifiableList(Arrays.asList(")
+        val configIter = configList.iterator()
+        while (configIter.hasNext()) {
+          val config = configIter.next()
+          out.print("new SupportedConfiguration(")
+          out.print("${escNullableString(config.version)}, ")
+          out.print("${escNullableString(config.type)}, ")
+          out.print("${escNullableString(config.default)}, ")
+          out.print("Arrays.asList(${quoteList(config.aliases)}), ")
+          out.print("Arrays.asList(${quoteList(config.propertyKeys)})")
+          out.print(")")
+          if (configIter.hasNext()) out.print(", ")
+        }
+        out.println(")));\n")
+      }
+      out.println("    SUPPORTED = Collections.unmodifiableMap(supportedMap);")
+      out.println()
+
+      // ALIASES
+      out.println("    // Note: This top-level alias mapping will be deprecated once Config Registry is mature enough to understand which version of a config a customer is using")
+      out.println("    Map<String, List<String>> aliasesMap = new HashMap<>();")
+      for ((canonical, list) in aliases.toSortedMap()) {
+        out.printf(
+          "    aliasesMap.put(\"%s\", Collections.unmodifiableList(Arrays.asList(%s)));\n",
+          esc(canonical),
+          quoteList(list)
+        )
+      }
+      out.println("    ALIASES = Collections.unmodifiableMap(aliasesMap);")
+      out.println()
+
+      // ALIAS_MAPPING
+      out.println("    Map<String, String> aliasMappingMap = new HashMap<>();")
+      for ((alias, target) in aliasMapping.toSortedMap()) {
+        out.printf("    aliasMappingMap.put(\"%s\", \"%s\");\n", esc(alias), esc(target))
+      }
+      out.println("    ALIAS_MAPPING = Collections.unmodifiableMap(aliasMappingMap);")
+      out.println()
+
+      // DEPRECATED
+      out.println("    Map<String, String> deprecatedMap = new HashMap<>();")
+      for ((oldKey, note) in deprecated.toSortedMap()) {
+        out.printf("    deprecatedMap.put(\"%s\", \"%s\");\n", esc(oldKey), esc(note))
+      }
+      out.println("    DEPRECATED = Collections.unmodifiableMap(deprecatedMap);")
+      out.println()
+
+      // REVERSE_PROPERTY_KEYS_MAP
+      out.println("    Map<String, String> reversePropertyKeysMapping = new HashMap<>();")
+      for ((propertyKey, config) in reversePropertyKeysMap.toSortedMap()) {
+        out.printf("    reversePropertyKeysMapping.put(\"%s\", \"%s\");\n", esc(propertyKey), esc(config))
+      }
+      out.println("    REVERSE_PROPERTY_KEYS_MAP = Collections.unmodifiableMap(reversePropertyKeysMapping);")
+      out.println()
+
+      out.println("  }")
+      out.println("}")
+    }
+  }
+
+  private fun quoteList(list: List<String>): String =
+    list.joinToString(", ") { "\"${esc(it)}\"" }
+
+  private fun esc(s: String): String =
+    s.replace("\\", "\\\\").replace("\"", "\\\"")
+
+  private fun escNullableString(s: String?): String =
+    if (s == null) "null" else "\"${esc(s)}\""
+}
+
+data class SupportedConfiguration(
+  val version: String?,
+  val type: String?,
+  val default: String?,
+  val aliases: List<String>,
+  val propertyKeys: List<String>
+)

utils/config-utils/src/main/java/datadog/trace/config/inversion/SupportedConfiguration.java

@@ -0,0 +1,44 @@
+package datadog.trace.config.inversion;
+
+import java.util.List;
+
+public class SupportedConfiguration {
+  private final String version;
+  private final String type;
+  private final String defaultValue;
+  private final List<String> aliases;
+  private final List<String> propertyKeys;
+
+  public SupportedConfiguration(
+      String version,
+      String type,
+      String defaultValue,
+      List<String> aliases,
+      List<String> propertyKeys) {
+    this.version = version;
+    this.type = type;
+    this.defaultValue = defaultValue;
+    this.aliases = aliases;
+    this.propertyKeys = propertyKeys;
+  }
+
+  public String version() {
+    return version;
+  }
+
+  public String type() {
+    return type;
+  }
+
+  public String defaultValue() {
+    return defaultValue;
+  }
+
+  public List<String> aliases() {
+    return aliases;
+  }
+
+  public List<String> propertyKeys() {
+    return propertyKeys;
+  }
+}