CHANGELOG for reproducible buildTar change / refactor tests

jib-core/CHANGELOG.md

@@ -8,6 +8,7 @@ All notable changes to this project will be documented in this file.
 ### Changed
 
 - `JavaContainerBuilder#fromDistroless()` and `JavaContainerBuilder#fromDistrolessJetty()` are deprecated. To migrate, check the Javadoc. ([#3123](https://github.com/GoogleContainerTools/jib/pull/3123))
+- Timestamps of file entries in a built `TarImage` are set to the epoch, making the tarball reproducible. ([#3158](https://github.com/GoogleContainerTools/jib/issues/3158))
 
 ### Fixed
 

jib-core/src/test/java/com/google/cloud/tools/jib/tar/TarStreamBuilderTest.java

@@ -16,7 +16,7 @@
 
 package com.google.cloud.tools.jib.tar;
 
-import static java.time.temporal.ChronoUnit.SECONDS;
+import static com.google.common.truth.Truth.assertThat;
 
 import com.google.cloud.tools.jib.blob.Blobs;
 import com.google.common.io.ByteStreams;
@@ -48,7 +48,7 @@ public class TarStreamBuilderTest {
   private Path directoryA;
   private byte[] fileAContents;
   private byte[] fileBContents;
-  private TarStreamBuilder testTarStreamBuilder = new TarStreamBuilder();
+  private final TarStreamBuilder testTarStreamBuilder = new TarStreamBuilder();
 
   @Before
   public void setup() throws URISyntaxException, IOException {
@@ -99,15 +99,12 @@ public void testToBlob_stringsAndTarArchiveEntriesWithCompression() throws IOExc
 
   @Test
   public void testToBlob_multiByte() throws IOException {
-    Instant modificationTime = Instant.ofEpochMilli(1618041179516L);
-    Instant timeFromTarArchiveEntry = modificationTime.truncatedTo(SECONDS);
-
     testTarStreamBuilder.addByteEntry(
-        "日本語".getBytes(StandardCharsets.UTF_8), "test", modificationTime);
+        "日本語".getBytes(StandardCharsets.UTF_8), "test", Instant.EPOCH);
     testTarStreamBuilder.addByteEntry(
-        "asdf".getBytes(StandardCharsets.UTF_8), "crepecake", modificationTime);
+        "asdf".getBytes(StandardCharsets.UTF_8), "crepecake", Instant.EPOCH);
     testTarStreamBuilder.addBlobEntry(
-        Blobs.from("jib"), "jib".getBytes(StandardCharsets.UTF_8).length, "jib", modificationTime);
+        Blobs.from("jib"), "jib".getBytes(StandardCharsets.UTF_8).length, "jib", Instant.EPOCH);
 
     // Writes the BLOB and captures the output.
     ByteArrayOutputStream tarByteOutputStream = new ByteArrayOutputStream();
@@ -130,17 +127,39 @@ public void testToBlob_multiByte() throws IOException {
     Assert.assertEquals("crepecake", headerFile.getName());
     Assert.assertEquals(
         "asdf", new String(ByteStreams.toByteArray(tarArchiveInputStream), StandardCharsets.UTF_8));
-    Assert.assertEquals(timeFromTarArchiveEntry, headerFile.getModTime().toInstant());
 
     headerFile = tarArchiveInputStream.getNextTarEntry();
     Assert.assertEquals("jib", headerFile.getName());
     Assert.assertEquals(
         "jib", new String(ByteStreams.toByteArray(tarArchiveInputStream), StandardCharsets.UTF_8));
-    Assert.assertEquals(timeFromTarArchiveEntry, headerFile.getModTime().toInstant());
 
     Assert.assertNull(tarArchiveInputStream.getNextTarEntry());
   }
 
+  @Test
+  public void testToBlob_modificationTime() throws IOException {
+    testTarStreamBuilder.addByteEntry(
+        "foo".getBytes(StandardCharsets.UTF_8), "foo", Instant.ofEpochSecond(1234));
+    testTarStreamBuilder.addBlobEntry(
+        Blobs.from("bar"),
+        "bar".getBytes(StandardCharsets.UTF_8).length,
+        "bar",
+        Instant.ofEpochSecond(3));
+
+    ByteArrayOutputStream outStream = new ByteArrayOutputStream();
+    testTarStreamBuilder.writeAsTarArchiveTo(outStream);
+
+    TarArchiveInputStream tarInStream =
+        new TarArchiveInputStream(new ByteArrayInputStream(outStream.toByteArray()));
+    TarArchiveEntry entry1 = tarInStream.getNextTarEntry();
+    TarArchiveEntry entry2 = tarInStream.getNextTarEntry();
+
+    assertThat(entry1.getName()).isEqualTo("foo");
+    assertThat(entry1.getModTime().toInstant()).isEqualTo(Instant.ofEpochSecond(1234));
+    assertThat(entry2.getName()).isEqualTo("bar");
+    assertThat(entry2.getModTime().toInstant()).isEqualTo(Instant.ofEpochSecond(3));
+  }
+
   /** Creates a TarStreamBuilder using TarArchiveEntries. */
   private void setUpWithTarEntries() {
     // Prepares a test TarStreamBuilder.

jib-gradle-plugin/CHANGELOG.md

@@ -7,6 +7,8 @@ All notable changes to this project will be documented in this file.
 
 ### Changed
 
+- Timestamps of file entries in a tarball built with `jibBuildTar` are set to the epoch, making the tarball reproducible. ([#3158](https://github.com/GoogleContainerTools/jib/issues/3158))
+
 ### Fixed
 
 ## 3.0.0

jib-maven-plugin/CHANGELOG.md

@@ -7,6 +7,8 @@ All notable changes to this project will be documented in this file.
 
 ### Changed
 
+- Timestamps of file entries in a tarball built with `jib:buildTar` are set to the epoch, making the tarball reproducible. ([#3158](https://github.com/GoogleContainerTools/jib/issues/3158))
+
 ### Fixed
 
 ## 3.0.0