added configureReproducible( int sourceDateEpoch ) API

Author: hboutemy

src/main/java/org/codehaus/plexus/archiver/AbstractArchiver.java

@@ -22,6 +22,7 @@
 import java.lang.reflect.UndeclaredThrowableException;
 import java.nio.charset.Charset;
 import java.util.ArrayList;
+import java.util.Calendar;
 import java.util.Comparator;
 import java.util.Date;
 import java.util.HashMap;
@@ -1257,4 +1258,31 @@ public String getOverrideGroupName()
     {
         return overrideGroupName;
     }
+
+    @Override
+    public void configureReproducible( int sourceDateEpoch )
+    {
+        // 1. force last modified date
+        setLastModifiedDate( convertSourceDateEpochToDate( sourceDateEpoch ) );
+
+        // 2. sort filenames in each directory when scanning filesystem
+        setFilenameComparator( new Comparator<String>()
+        {
+            @Override
+            public int compare( String s1, String s2 )
+            {
+                return s1.compareTo( s2 );
+            }
+        } );
+
+        // 3. ignore file/directory mode from filesystem, since they may vary based on local user umask
+        // notice: this overrides execute bit on Unix (that is already ignored on Windows)
+        setFileMode( Archiver.DEFAULT_FILE_MODE );
+        setDirectoryMode( Archiver.DEFAULT_DIR_MODE );
+    }
+
+    protected Date convertSourceDateEpochToDate( int sourceDateEpoch )
+    {
+        return new Date( sourceDateEpoch * 1000L );
+    }
 }

src/main/java/org/codehaus/plexus/archiver/Archiver.java

@@ -415,11 +415,15 @@ ResourceIterator getResources()
     Date getLastModifiedDate();
 
     /**
+     * Set filename comparator, used to sort file entries when scanning directories since File.list() does not
+     * guarantee any order.
+     *
      * @since 4.2.0
      */
     void setFilenameComparator( Comparator<String> filenameComparator );
 
     /**
+<<<<<<< reproducible
      * @since 4.2.0
      */
     void setOverrideUid( int uid );
@@ -458,4 +462,17 @@ ResourceIterator getResources()
      * @since 4.2.0
      */
     String getOverrideGroupName();
+
+    /**
+     * Configure the archiver to get reproducible archives (see <a href="https://reproducible-builds.org/>Reproducible
+     * Builds</a>). This will require reproducible archive entries order, defined entries timestamp and reproducible
+     * entries Unix mode.
+     * 
+     * @param sourceDateEpoch Value like SOURCE_DATE_EPOCH as
+     *            <a href="https://reproducible-builds.org/specs/source-date-epoch/">defined in Reproducible Builds</a>:
+     *            a UNIX timestamp, defined as the number of seconds, excluding leap seconds, since 01 Jan 1970 00:00:00
+     *            UTC.
+     * @since 4.2.0
+     */
+    void configureReproducible( int sourceDateEpoch );
 }

src/main/java/org/codehaus/plexus/archiver/diags/DelgatingArchiver.java

@@ -398,4 +398,11 @@ public String getOverrideGroupName()
     {
         return target.getOverrideGroupName();
     }
+
+    @Override
+    public void configureReproducible( int sourceDateEpoch )
+    {
+        target.configureReproducible( sourceDateEpoch );
+    }
+
 }

src/main/java/org/codehaus/plexus/archiver/diags/NoOpArchiver.java

@@ -414,4 +414,10 @@ public String getOverrideGroupName()
         return null;
     }
 
+    @Override
+    public void configureReproducible( int sourceDateEpoch )
+    {
+
+    }
+
 }

src/main/java/org/codehaus/plexus/archiver/diags/TrackingArchiver.java

@@ -468,4 +468,9 @@ public String getOverrideGroupName()
     {
         return null;
     }
+
+    @Override
+    public void configureReproducible( int sourceDateEpoch )
+    {
+    }
 }

src/main/java/org/codehaus/plexus/archiver/zip/AbstractZipArchiver.java

@@ -24,6 +24,8 @@
 import java.io.OutputStream;
 import java.nio.ByteBuffer;
 import java.nio.charset.Charset;
+import java.util.Calendar;
+import java.util.Date;
 import java.util.Hashtable;
 import java.util.Stack;
 import java.util.concurrent.ExecutionException;
@@ -833,4 +835,13 @@ protected String getArchiveType()
         return archiveType;
     }
 
+    @Override
+    protected Date convertSourceDateEpochToDate( int sourceDateEpoch )
+    {
+        // timestamp of zip entries at zip storage level ignores timezone: see https://github.com/Stuk/jszip/issues/369
+        Calendar cal = Calendar.getInstance();
+        long zipTime = 1000L * sourceDateEpoch - ( cal.get( Calendar.ZONE_OFFSET ) + cal.get( Calendar.DST_OFFSET ) );
+        return new Date( zipTime );
+    }
+
 }