From 71bfa94d1019c6bdae9979d0ae25d7c9536fe665 Mon Sep 17 00:00:00 2001
From: Andy Wilkinson <andy.wilkinson@broadcom.com>
Date: Fri, 4 Sep 2026 11:12:11 +0100
Subject: [PATCH] Polish "Delete layer temp file when layer creation fails"

See gh-51519

Signed-off-by: Andy Wilkinson <andy.wilkinson@broadcom.com>
---
 .../platform/build/ImageBuildpack.java        | 41 ++++++++++---------
 1 file changed, 22 insertions(+), 19 deletions(-)

diff --git a/buildpack/spring-boot-buildpack-platform/src/main/java/org/springframework/boot/buildpack/platform/build/ImageBuildpack.java b/buildpack/spring-boot-buildpack-platform/src/main/java/org/springframework/boot/buildpack/platform/build/ImageBuildpack.java
index eb8d74e46fb..c596ade2acd 100644
--- a/buildpack/spring-boot-buildpack-platform/src/main/java/org/springframework/boot/buildpack/platform/build/ImageBuildpack.java
+++ b/buildpack/spring-boot-buildpack-platform/src/main/java/org/springframework/boot/buildpack/platform/build/ImageBuildpack.java
@@ -139,25 +139,7 @@ final class ImageBuildpack implements Buildpack {
 				}
 				Path layerFile = Files.createTempFile("create-builder-scratch-", null);
 				try {
-					try (TarArchiveOutputStream out = new TarArchiveOutputStream(Files.newOutputStream(layerFile))) {
-						try (TarArchiveInputStream in = new TarArchiveInputStream(
-								Files.newInputStream(sourceTarFile))) {
-							out.setLongFileMode(TarArchiveOutputStream.LONGFILE_POSIX);
-							TarArchiveEntry entry = in.getNextEntry();
-							while (entry != null) {
-								String entryName = entry.getName();
-								Path entryPath = Path.of(entryName);
-								Assert.state(entryPath.toAbsolutePath().equals(entryPath.toAbsolutePath().normalize()),
-										() -> "Malformed zip entry name '%s'".formatted(entryName));
-								out.putArchiveEntry(entry);
-								StreamUtils.copy(in, out);
-								out.closeArchiveEntry();
-								entry = in.getNextEntry();
-							}
-							out.finish();
-						}
-					}
-					return layerFile;
+					writeLayerFile(layerFile, sourceTarFile);
 				}
 				catch (IOException | RuntimeException ex) {
 					try {
@@ -168,12 +150,33 @@ final class ImageBuildpack implements Buildpack {
 					}
 					throw ex;
 				}
+				return layerFile;
 			}
 			finally {
 				Files.deleteIfExists(sourceTarFile);
 			}
 		}
 
+		private void writeLayerFile(Path layerFile, Path sourceTarFile) throws IOException {
+			try (TarArchiveOutputStream out = new TarArchiveOutputStream(Files.newOutputStream(layerFile))) {
+				try (TarArchiveInputStream in = new TarArchiveInputStream(Files.newInputStream(sourceTarFile))) {
+					out.setLongFileMode(TarArchiveOutputStream.LONGFILE_POSIX);
+					TarArchiveEntry entry = in.getNextEntry();
+					while (entry != null) {
+						String entryName = entry.getName();
+						Path entryPath = Path.of(entryName);
+						Assert.state(entryPath.toAbsolutePath().equals(entryPath.toAbsolutePath().normalize()),
+								() -> "Malformed zip entry name '%s'".formatted(entryName));
+						out.putArchiveEntry(entry);
+						StreamUtils.copy(in, out);
+						out.closeArchiveEntry();
+						entry = in.getNextEntry();
+					}
+					out.finish();
+				}
+			}
+		}
+
 		void apply(IOConsumer<Layer> layers) throws IOException {
 			for (Path path : this.layerFiles) {
 				layers.accept(Layer.fromTarArchive((out) -> {