GoogleContainerTools#3158 - [Jib core] Tar archives with same contents are not reproducible

Author: davidtron

jib-core/src/main/java/com/google/cloud/tools/jib/image/ImageTarball.java

@@ -31,6 +31,7 @@
 import java.io.IOException;
 import java.io.OutputStream;
 import java.nio.charset.StandardCharsets;
+import java.time.Instant;
 import java.util.Collections;
 
 /** Translates an {@link Image} to a tarball that can be loaded into Docker. */
@@ -48,6 +49,7 @@ public class ImageTarball {
   private final Image image;
   private final ImageReference imageReference;
   private final ImmutableSet<String> allTargetImageTags;
+  private final Instant creationTime = Instant.EPOCH;
 
   /**
    * Instantiate with an {@link Image}.
@@ -88,7 +90,8 @@ private void ociWriteTo(OutputStream out) throws IOException {
       DescriptorDigest digest = layer.getBlobDescriptor().getDigest();
       long size = layer.getBlobDescriptor().getSize();
 
-      tarStreamBuilder.addBlobEntry(layer.getBlob(), size, "blobs/sha256/" + digest.getHash());
+      tarStreamBuilder.addBlobEntry(
+          layer.getBlob(), size, "blobs/sha256/" + digest.getHash(), creationTime);
       manifest.addLayer(size, digest);
     }
 
@@ -99,21 +102,26 @@ private void ociWriteTo(OutputStream out) throws IOException {
     manifest.setContainerConfiguration(configDescriptor.getSize(), configDescriptor.getDigest());
     tarStreamBuilder.addByteEntry(
         JsonTemplateMapper.toByteArray(containerConfiguration),
-        "blobs/sha256/" + configDescriptor.getDigest().getHash());
+        "blobs/sha256/" + configDescriptor.getDigest().getHash(),
+        creationTime);
 
     // Adds the manifest to the tarball
     BlobDescriptor manifestDescriptor = Digests.computeDigest(manifest);
     tarStreamBuilder.addByteEntry(
         JsonTemplateMapper.toByteArray(manifest),
-        "blobs/sha256/" + manifestDescriptor.getDigest().getHash());
+        "blobs/sha256/" + manifestDescriptor.getDigest().getHash(),
+        creationTime);
 
     // Adds the oci-layout and index.json
     tarStreamBuilder.addByteEntry(
-        "{\"imageLayoutVersion\": \"1.0.0\"}".getBytes(StandardCharsets.UTF_8), "oci-layout");
+        "{\"imageLayoutVersion\": \"1.0.0\"}".getBytes(StandardCharsets.UTF_8),
+        "oci-layout",
+        creationTime);
     OciIndexTemplate index = new OciIndexTemplate();
     // TODO: figure out how to tag with allTargetImageTags
     index.addManifest(manifestDescriptor, imageReference.toStringWithQualifier());
-    tarStreamBuilder.addByteEntry(JsonTemplateMapper.toByteArray(index), "index.json");
+    tarStreamBuilder.addByteEntry(
+        JsonTemplateMapper.toByteArray(index), "index.json", creationTime);
 
     tarStreamBuilder.writeAsTarArchiveTo(out);
   }
@@ -127,7 +135,7 @@ private void dockerWriteTo(OutputStream out) throws IOException {
       String layerName = layer.getBlobDescriptor().getDigest().getHash() + LAYER_FILE_EXTENSION;
 
       tarStreamBuilder.addBlobEntry(
-          layer.getBlob(), layer.getBlobDescriptor().getSize(), layerName);
+          layer.getBlob(), layer.getBlobDescriptor().getSize(), layerName, creationTime);
       manifestTemplate.addLayerFile(layerName);
     }
 
@@ -136,15 +144,17 @@ private void dockerWriteTo(OutputStream out) throws IOException {
         new ImageToJsonTranslator(image).getContainerConfiguration();
     tarStreamBuilder.addByteEntry(
         JsonTemplateMapper.toByteArray(containerConfiguration),
-        CONTAINER_CONFIGURATION_JSON_FILE_NAME);
+        CONTAINER_CONFIGURATION_JSON_FILE_NAME,
+        creationTime);
 
     // Adds the manifest to tarball.
     for (String tag : allTargetImageTags) {
       manifestTemplate.addRepoTag(imageReference.withQualifier(tag).toStringWithQualifier());
     }
     tarStreamBuilder.addByteEntry(
         JsonTemplateMapper.toByteArray(Collections.singletonList(manifestTemplate)),
-        MANIFEST_JSON_FILE_NAME);
+        MANIFEST_JSON_FILE_NAME,
+        creationTime);
 
     tarStreamBuilder.writeAsTarArchiveTo(out);
   }

jib-core/src/main/java/com/google/cloud/tools/jib/tar/TarStreamBuilder.java

@@ -21,6 +21,7 @@
 import java.io.IOException;
 import java.io.OutputStream;
 import java.nio.charset.StandardCharsets;
+import java.time.Instant;
 import java.util.LinkedHashMap;
 import java.util.Map;
 import org.apache.commons.compress.archivers.tar.TarArchiveEntry;
@@ -71,10 +72,12 @@ public void addTarArchiveEntry(TarArchiveEntry entry) {
    *
    * @param contents the bytes to add to the tarball
    * @param name the name of the entry (i.e. filename)
+   * @param modTime the time the entry is created
    */
-  public void addByteEntry(byte[] contents, String name) {
+  public void addByteEntry(byte[] contents, String name, Instant modTime) {
     TarArchiveEntry entry = new TarArchiveEntry(name);
     entry.setSize(contents.length);
+    entry.setModTime(modTime.getEpochSecond());
     archiveMap.put(entry, Blobs.from(outputStream -> outputStream.write(contents)));
   }
 
@@ -85,10 +88,12 @@ public void addByteEntry(byte[] contents, String name) {
    * @param blob the {@link Blob} to add to the tarball
    * @param size the size (in bytes) of {@code blob}
    * @param name the name of the entry (i.e. filename)
+   * @param modTime the time the entry is created
    */
-  public void addBlobEntry(Blob blob, long size, String name) {
+  public void addBlobEntry(Blob blob, long size, String name, Instant modTime) {
     TarArchiveEntry entry = new TarArchiveEntry(name);
     entry.setSize(size);
+    entry.setModTime(modTime.getEpochSecond());
     archiveMap.put(entry, blob);
   }
 }

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

@@ -29,6 +29,7 @@
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.Paths;
+import java.time.Instant;
 import java.util.zip.GZIPInputStream;
 import java.util.zip.GZIPOutputStream;
 import org.apache.commons.compress.archivers.tar.TarArchiveEntry;
@@ -46,6 +47,7 @@ public class TarStreamBuilderTest {
   private byte[] fileAContents;
   private byte[] fileBContents;
   private TarStreamBuilder testTarStreamBuilder = new TarStreamBuilder();
+  private final Instant creationTime = Instant.EPOCH;
 
   @Before
   public void setup() throws URISyntaxException, IOException {
@@ -96,10 +98,11 @@ public void testToBlob_stringsAndTarArchiveEntriesWithCompression() throws IOExc
 
   @Test
   public void testToBlob_multiByte() throws IOException {
-    testTarStreamBuilder.addByteEntry("日本語".getBytes(StandardCharsets.UTF_8), "test");
-    testTarStreamBuilder.addByteEntry("asdf".getBytes(StandardCharsets.UTF_8), "crepecake");
+    testTarStreamBuilder.addByteEntry("日本語".getBytes(StandardCharsets.UTF_8), "test", creationTime);
+    testTarStreamBuilder.addByteEntry(
+        "asdf".getBytes(StandardCharsets.UTF_8), "crepecake", creationTime);
     testTarStreamBuilder.addBlobEntry(
-        Blobs.from("jib"), "jib".getBytes(StandardCharsets.UTF_8).length, "jib");
+        Blobs.from("jib"), "jib".getBytes(StandardCharsets.UTF_8).length, "jib", creationTime);
 
     // Writes the BLOB and captures the output.
     ByteArrayOutputStream tarByteOutputStream = new ByteArrayOutputStream();
@@ -148,25 +151,27 @@ private void setUpWithTarEntries() {
   /** Creates a TarStreamBuilder using Strings. */
   private void setUpWithStrings() {
     // Prepares a test TarStreamBuilder.
-    testTarStreamBuilder.addByteEntry(fileAContents, "some/path/to/resourceFileA");
-    testTarStreamBuilder.addByteEntry(fileBContents, "crepecake");
+    testTarStreamBuilder.addByteEntry(fileAContents, "some/path/to/resourceFileA", creationTime);
+    testTarStreamBuilder.addByteEntry(fileBContents, "crepecake", creationTime);
     testTarStreamBuilder.addTarArchiveEntry(
         new TarArchiveEntry(directoryA.toFile(), "some/path/to"));
     testTarStreamBuilder.addByteEntry(
         fileAContents,
-        "some/really/long/path/that/exceeds/100/characters/abcdefghijklmnopqrstuvwxyz0123456789012345678901234567890");
+        "some/really/long/path/that/exceeds/100/characters/abcdefghijklmnopqrstuvwxyz0123456789012345678901234567890",
+        creationTime);
   }
 
   /** Creates a TarStreamBuilder using Strings and TarArchiveEntries. */
   private void setUpWithStringsAndTarEntries() {
     // Prepares a test TarStreamBuilder.
-    testTarStreamBuilder.addByteEntry(fileAContents, "some/path/to/resourceFileA");
+    testTarStreamBuilder.addByteEntry(fileAContents, "some/path/to/resourceFileA", creationTime);
     testTarStreamBuilder.addTarArchiveEntry(new TarArchiveEntry(fileB.toFile(), "crepecake"));
     testTarStreamBuilder.addTarArchiveEntry(
         new TarArchiveEntry(directoryA.toFile(), "some/path/to"));
     testTarStreamBuilder.addByteEntry(
         fileAContents,
-        "some/really/long/path/that/exceeds/100/characters/abcdefghijklmnopqrstuvwxyz0123456789012345678901234567890");
+        "some/really/long/path/that/exceeds/100/characters/abcdefghijklmnopqrstuvwxyz0123456789012345678901234567890",
+        creationTime);
   }
 
   /** Creates a compressed blob from the TarStreamBuilder and verifies it. */