Render byte arrays in the CLI as a hex dump

presto-cli/src/main/java/com/facebook/presto/cli/AlignedTablePrinter.java

@@ -13,6 +13,8 @@
  */
 package com.facebook.presto.cli;
 
+import com.google.common.base.Function;
+import com.google.common.base.Joiner;
 import com.google.common.base.Splitter;
 import com.google.common.collect.ImmutableList;
 import org.fusesource.jansi.AnsiString;
@@ -25,13 +27,19 @@
 import static com.google.common.base.Preconditions.checkNotNull;
 import static com.google.common.base.Preconditions.checkState;
 import static com.google.common.base.Strings.repeat;
+import static com.google.common.collect.Iterables.partition;
+import static com.google.common.collect.Iterables.transform;
+import static com.google.common.io.BaseEncoding.base16;
 import static java.lang.Math.max;
 import static java.lang.String.format;
 
 public class AlignedTablePrinter
         implements OutputPrinter
 {
     private static final Splitter LINE_SPLITTER = Splitter.on('\n');
+    private static final Splitter HEX_SPLITTER = Splitter.fixedLength(2);
+    private static final Joiner HEX_BYTE_JOINER = Joiner.on(' ');
+    private static final Joiner HEX_LINE_JOINER = Joiner.on('\n');
 
     private final List<String> fieldNames;
     private final Writer writer;
@@ -126,7 +134,45 @@ public void printRows(List<List<?>> rows, boolean complete)
 
     static String formatValue(Object o)
     {
-        return (o == null) ? "NULL" : o.toString();
+        if (o == null) {
+            return "NULL";
+        }
+
+        if (o instanceof byte[]) {
+            return formatHexDump((byte[]) o, 16);
+        }
+
+        return o.toString();
+    }
+
+    private static String formatHexDump(byte[] bytes, int bytesPerLine)
+    {
+        // hex dump: "616263"
+        String hexDump = base16().lowerCase().encode(bytes);
+
+        // hex pairs: ["61", "62", "63"]
+        Iterable<String> hexPairs = HEX_SPLITTER.split(hexDump);
+
+        // hex lines: [["61", "62", "63], [...]]
+        Iterable<List<String>> hexLines = partition(hexPairs, bytesPerLine);
+
+        // lines: ["61 62 63", ...]
+        Iterable<String> lines = transform(hexLines, joinerFunction(HEX_BYTE_JOINER));
+
+        // joined: "61 62 63\n..."
+        return HEX_LINE_JOINER.join(lines);
+    }
+
+    private static Function<Iterable<String>, String> joinerFunction(final Joiner joiner)
+    {
+        return new Function<Iterable<String>, String>()
+        {
+            @Override
+            public String apply(Iterable<String> iterable)
+            {
+                return joiner.join(iterable);
+            }
+        };
     }
 
     private static String center(String s, int maxWidth, int padding)

presto-cli/src/test/java/com/facebook/presto/cli/TestAlignedTablePrinter.java

@@ -19,6 +19,7 @@
 import java.io.StringWriter;
 import java.util.List;
 
+import static java.nio.charset.StandardCharsets.UTF_8;
 import static java.util.Arrays.asList;
 import static org.testng.Assert.assertEquals;
 
@@ -95,6 +96,34 @@ public void testAlignedPrintingNoRows()
         assertEquals(writer.getBuffer().toString(), expected);
     }
 
+    @Test
+    public void testAlignedPrintingHex()
+            throws Exception
+    {
+        StringWriter writer = new StringWriter();
+        List<String> fieldNames = ImmutableList.of("first", "binary", "last");
+        OutputPrinter printer = new AlignedTablePrinter(fieldNames, writer);
+
+        printer.printRows(rows(
+                        row("hello", bytes("hello"), "world"),
+                        row("a", bytes("some long text that is more than 16 bytes"), "b"),
+                        row("cat", bytes(""), "dog")),
+                true);
+        printer.finish();
+
+        String expected = "" +
+                " first |                     binary                      | last  \n" +
+                "-------+-------------------------------------------------+-------\n" +
+                " hello | 68 65 6c 6c 6f                                  | world \n" +
+                " a     | 73 6f 6d 65 20 6c 6f 6e 67 20 74 65 78 74 20 74+| b     \n" +
+                "       | 68 61 74 20 69 73 20 6d 6f 72 65 20 74 68 61 6e+|       \n" +
+                "       | 20 31 36 20 62 79 74 65 73                      |       \n" +
+                " cat   |                                                 | dog   \n" +
+                "(3 rows)\n";
+
+        assertEquals(writer.getBuffer().toString(), expected);
+    }
+
     static List<?> row(Object... values)
     {
         return asList(values);
@@ -104,4 +133,9 @@ static List<List<?>> rows(List<?>... rows)
     {
         return asList(rows);
     }
+
+    static byte[] bytes(String s)
+    {
+        return s.getBytes(UTF_8);
+    }
 }

presto-cli/src/test/java/com/facebook/presto/cli/TestVerticalRecordPrinter.java

@@ -19,6 +19,7 @@
 import java.io.StringWriter;
 import java.util.List;
 
+import static com.facebook.presto.cli.TestAlignedTablePrinter.bytes;
 import static com.facebook.presto.cli.TestAlignedTablePrinter.row;
 import static com.facebook.presto.cli.TestAlignedTablePrinter.rows;
 import static org.testng.Assert.assertEquals;
@@ -133,4 +134,38 @@ public void testVerticalPrintingNoRows()
 
         assertEquals(writer.getBuffer().toString(), "(no rows)\n");
     }
+
+    @Test
+    public void testVerticalPrintingHex()
+            throws Exception
+    {
+        StringWriter writer = new StringWriter();
+        List<String> fieldNames = ImmutableList.of("first", "binary", "last");
+        OutputPrinter printer = new VerticalRecordPrinter(fieldNames, writer);
+
+        printer.printRows(rows(
+                        row("hello", bytes("hello"), "world"),
+                        row("a", bytes("some long text that is more than 16 bytes"), "b"),
+                        row("cat", bytes(""), "dog")),
+                true);
+        printer.finish();
+
+        String expected = "" +
+                "-[ RECORD 1 ]-------------------------------------------\n" +
+                "first  | hello\n" +
+                "binary | 68 65 6c 6c 6f\n" +
+                "last   | world\n" +
+                "-[ RECORD 2 ]-------------------------------------------\n" +
+                "first  | a\n" +
+                "binary | 73 6f 6d 65 20 6c 6f 6e 67 20 74 65 78 74 20 74\n" +
+                "       | 68 61 74 20 69 73 20 6d 6f 72 65 20 74 68 61 6e\n" +
+                "       | 20 31 36 20 62 79 74 65 73\n" +
+                "last   | b\n" +
+                "-[ RECORD 3 ]-------------------------------------------\n" +
+                "first  | cat\n" +
+                "binary | \n" +
+                "last   | dog\n";
+
+        assertEquals(writer.getBuffer().toString(), expected);
+    }
 }

presto-docs/src/main/sphinx/release/release-0.80.rst

@@ -11,3 +11,6 @@ General Changes
 
 * Add property ``task.verbose-stats`` to enable verbose statistics collection for
   tasks. The default is ``false``.
+
+* Format binary data in the CLI as a hex dump.
+