Configurable source path patterns for Apache license/notice resource transformers

docs/changes/README.md

@@ -8,6 +8,8 @@
 - Change the group of `startShadowScripts` from `application` to `other`. ([#1797](https://github.com/GradleUp/shadow/pull/1797))
 - Update ASM and jdependency to support Java 26. ([#1799](https://github.com/GradleUp/shadow/pull/1799))
 - Bump min Gradle requirement to 9.0.0. ([#1801](https://github.com/GradleUp/shadow/pull/1801))
+- Fix `ApacheLicenseResourceTransformer` to not remove `META-INF/LICENSE*` files ([#1842](https://github.com/GradleUp/shadow/pull/1842))
+- Configurable match-patterns for `ApacheLicenseResourceTransformer` + `ApacheNoticeResourceTransformer` files ([#1842](https://github.com/GradleUp/shadow/pull/1845))
 
 ## [9.2.2](https://github.com/GradleUp/shadow/compare/9.2.2) - 2025-09-26
 

src/main/kotlin/com/github/jengelman/gradle/plugins/shadow/transformers/ApacheLicenseResourceTransformer.kt

@@ -1,6 +1,15 @@
 package com.github.jengelman.gradle.plugins.shadow.transformers
 
+import com.github.jengelman.gradle.plugins.shadow.internal.property
+import com.github.jengelman.gradle.plugins.shadow.internal.zipEntry
+import java.nio.charset.StandardCharsets
+import javax.inject.Inject
+import org.apache.tools.zip.ZipOutputStream
 import org.gradle.api.file.FileTreeElement
+import org.gradle.api.model.ObjectFactory
+import org.gradle.api.provider.Property
+import org.gradle.api.provider.SetProperty
+import org.gradle.api.tasks.Input
 
 /**
  * Prevents duplicate copies of the license.
@@ -10,17 +19,88 @@ import org.gradle.api.file.FileTreeElement
  * @author John Engelman
  */
 @CacheableTransformer
-public open class ApacheLicenseResourceTransformer : ResourceTransformer by ResourceTransformer.Companion {
+public open class ApacheLicenseResourceTransformer @Inject constructor(
+  final override val objectFactory: ObjectFactory,
+) : ResourceTransformer by ResourceTransformer.Companion {
+
+  private val elements: MutableSet<String> = LinkedHashSet()
+
+  /**
+   * Paths to consider as a license files, evaluated using `it.equals(path, ignoreCase = true)`.
+   *
+   * Defaults to `META-INF/LICENSE`.
+   */
+  @get:Input
+  public open val paths: SetProperty<String> = objectFactory.setProperty(String::class.java).value(setOf("META-INF/LICENSE"))
+
+  /**
+   * Paths to consider as a license files, evaluated using `it.regionMatches(0, path, 0, it.length, ignoreCase = true)`.
+   *
+   * Defaults to `META-INF/LICENSE.txt` and `META-INF/LICENSE.md`.
+   */
+  @get:Input
+  public open val regionMatchPaths: SetProperty<String> = objectFactory.setProperty(String::class.java).value(setOf("META-INF/LICENSE.txt", "META-INF/LICENSE.md"))
+
+  /**
+   * Path of the resulting output file.
+   *
+   * Defaults to `META-INF/LICENSE`.
+   */
+  @get:Input
+  public open val outputPath: Property<String> = objectFactory.property("META-INF/LICENSE")
+
+  /**
+   * Whether to include an empty output, if no input file matches.
+   *
+   * Defaults to `false`.
+   */
+  @get:Input
+  public open val writeEmpty: Property<Boolean> = objectFactory.property(false)
+
+  /**
+   * The file encoding of the `LICENSE` file.
+   */
+  @get:Input
+  public open val charsetName: Property<String> = objectFactory.property(Charsets.UTF_8.name())
+
+  /**
+   * The separator placed between two licenses.
+   */
+  @get:Input
+  public open val separator: Property<String> = objectFactory.property("\n\n${"-".repeat(120)}\n\n")
+
   override fun canTransformResource(element: FileTreeElement): Boolean {
     val path = element.path
-    return LICENSE_PATH.equals(path, ignoreCase = true) ||
-      LICENSE_TXT_PATH.regionMatches(0, path, 0, LICENSE_TXT_PATH.length, ignoreCase = true) ||
-      LICENSE_MD_PATH.regionMatches(0, path, 0, LICENSE_MD_PATH.length, ignoreCase = true)
+    return paths.get().any {
+      it.equals(path, ignoreCase = true)
+    } || regionMatchPaths.get().any {
+      it.regionMatches(0, path, 0, it.length, ignoreCase = true)
+    }
   }
 
-  private companion object {
-    private const val LICENSE_PATH = "META-INF/LICENSE"
-    private const val LICENSE_TXT_PATH = "META-INF/LICENSE.txt"
-    private const val LICENSE_MD_PATH = "META-INF/LICENSE.md"
+  override fun transform(context: TransformerContext) {
+    val bytes = context.inputStream.readAllBytes()
+    val content = bytes.toString(StandardCharsets.UTF_8).trim('\n', '\r')
+    if (!content.isEmpty()) {
+      elements.add(content)
+    }
+  }
+
+  override fun hasTransformedResource(): Boolean = true
+
+  override fun modifyOutputStream(os: ZipOutputStream, preserveFileTimestamps: Boolean) {
+    if (!elements.isEmpty()) {
+      os.putNextEntry(zipEntry(outputPath.get(), preserveFileTimestamps))
+      var first = true
+      val separator = separator.get().toByteArray(StandardCharsets.UTF_8)
+      for (element in elements) {
+        if (!first) {
+          os.write(separator)
+        }
+        os.write(element.toByteArray(StandardCharsets.UTF_8))
+        first = false
+      }
+      os.closeEntry()
+    }
   }
 }

src/main/kotlin/com/github/jengelman/gradle/plugins/shadow/transformers/ApacheNoticeResourceTransformer.kt

@@ -12,6 +12,7 @@ import org.apache.tools.zip.ZipOutputStream
 import org.gradle.api.file.FileTreeElement
 import org.gradle.api.model.ObjectFactory
 import org.gradle.api.provider.Property
+import org.gradle.api.provider.SetProperty
 import org.gradle.api.tasks.Input
 
 /**
@@ -34,6 +35,30 @@ public open class ApacheNoticeResourceTransformer @Inject constructor(
    */
   private var fallbackCopyright: String? = null
 
+  /**
+   * Paths to consider as a notice files, evaluated using `it.equals(path, ignoreCase = true)`.
+   *
+   * Defaults to `META-INF/NOTICE`.
+   */
+  @get:Input
+  public open val paths: SetProperty<String> = objectFactory.setProperty(String::class.java).value(setOf("META-INF/NOTICE"))
+
+  /**
+   * Paths to consider as a notice files, evaluated using `it.regionMatches(0, path, 0, it.length, ignoreCase = true)`.
+   *
+   * Defaults to `META-INF/NOTICE.txt` and `META-INF/NOTICE.md`.
+   */
+  @get:Input
+  public open val regionMatchPaths: SetProperty<String> = objectFactory.setProperty(String::class.java).value(setOf("META-INF/NOTICE.txt", "META-INF/NOTICE.md"))
+
+  /**
+   * Path of the resulting output file.
+   *
+   * Defaults to `META-INF/NOTICE`.
+   */
+  @get:Input
+  public open val outputPath: Property<String> = objectFactory.property("META-INF/NOTICE")
+
   @get:Input
   public open val projectName: Property<String> = objectFactory.property("")
 
@@ -77,9 +102,11 @@ public open class ApacheNoticeResourceTransformer @Inject constructor(
 
   override fun canTransformResource(element: FileTreeElement): Boolean {
     val path = element.path
-    return NOTICE_PATH.equals(path, ignoreCase = true) ||
-      NOTICE_TXT_PATH.equals(path, ignoreCase = true) ||
-      NOTICE_MD_PATH.equals(path, ignoreCase = true)
+    return paths.get().any {
+      it.equals(path, ignoreCase = true)
+    } || regionMatchPaths.get().any {
+      it.regionMatches(0, path, 0, it.length, ignoreCase = true)
+    }
   }
 
   override fun transform(context: TransformerContext) {
@@ -184,16 +211,10 @@ public open class ApacheNoticeResourceTransformer @Inject constructor(
       }
     }
 
-    os.putNextEntry(zipEntry(NOTICE_PATH, preserveFileTimestamps))
+    os.putNextEntry(zipEntry(outputPath.get(), preserveFileTimestamps))
     os.write(sb.toString().trim().toByteArray(charset))
     os.closeEntry()
 
     entries.clear()
   }
-
-  private companion object {
-    private const val NOTICE_PATH = "META-INF/NOTICE"
-    private const val NOTICE_TXT_PATH = "META-INF/NOTICE.txt"
-    private const val NOTICE_MD_PATH = "META-INF/NOTICE.md"
-  }
 }

src/test/kotlin/com/github/jengelman/gradle/plugins/shadow/transformers/ApacheLicenseResourceTransformerTest.kt

@@ -1,8 +1,13 @@
 package com.github.jengelman.gradle.plugins.shadow.transformers
 
 import assertk.assertThat
+import assertk.assertions.isEqualTo
 import assertk.assertions.isFalse
 import assertk.assertions.isTrue
+import java.io.ByteArrayOutputStream
+import java.nio.charset.Charset
+import java.util.zip.ZipInputStream
+import org.apache.tools.zip.ZipOutputStream
 import org.junit.jupiter.api.Test
 
 /**
@@ -23,4 +28,34 @@ class ApacheLicenseResourceTransformerTest : BaseTransformerTest<ApacheLicenseRe
     assertThat(transformer.canTransformResource("META-INF/License.md")).isTrue()
     assertThat(transformer.canTransformResource("META-INF/MANIFEST.MF")).isFalse()
   }
+
+  @Test
+  fun licensesAreIncluded() {
+    val baos = ByteArrayOutputStream()
+    val zos = ZipOutputStream(baos)
+
+    transformer.separator.set("\n---\n")
+    transformer.transform(TransformerContext("META-INF/LICENSE", "License 1".byteInputStream()))
+    transformer.transform(TransformerContext("META-INF/LICENSE.txt", "License 2".byteInputStream()))
+    transformer.transform(TransformerContext("META-INF/LICENSE.md", "License 3".byteInputStream()))
+    transformer.transform(TransformerContext("META-INF/LICENSE.txt", "License 1".byteInputStream()))
+    transformer.transform(TransformerContext("META-INF/LICENSE.txt", "\n\r\nLicense 2".byteInputStream()))
+    transformer.transform(TransformerContext("META-INF/LICENSE.txt", "\n\r\nLicense 2\n\r\n".byteInputStream()))
+    transformer.modifyOutputStream(zos, false)
+    zos.close()
+
+    val zis = ZipInputStream(baos.toByteArray().inputStream())
+    zis.nextEntry
+    val output = zis.readAllBytes().toString(Charset.forName(transformer.charsetName.get()))
+
+    assertThat(output).isEqualTo(
+      """
+      License 1
+      ---
+      License 2
+      ---
+      License 3
+      """.trimIndent(),
+    )
+  }
 }