Save DataTable metadata in records if added during archiving. (#14671)3.12.0-b1

* Save DataTable metadata in records if added during archiving.

* Use descriptive and rare string row label.

2 files changed, 70 insertions, 1 deletions

diff --git a/core/DataTable.php b/core/DataTable.php
index 727cc5dd01..356ce86f69 100644
--- a/core/DataTable.php
+++ b/core/DataTable.php
@@ -200,9 +200,17 @@ class DataTable implements DataTableInterface, \IteratorAggregate, \ArrayAccess
     /** The ID of the Summary Row. */
     const ID_SUMMARY_ROW = -1;
 
+    /**
+     * The ID of the special metadata row. This row only exists in the serialized row data and stores the datatable metadata.
+     *
+     * This allows us to save datatable metadata in archive data.
+     */
+    const ID_ARCHIVED_METADATA_ROW = -3;
+
     /** The original label of the Summary Row. */
     const LABEL_SUMMARY_ROW = -1;
     const LABEL_TOTALS_ROW = -2;
+    const LABEL_ARCHIVED_METADATA_ROW = '__datatable_metadata__';
 
     /**
      * Name for metadata that contains extra {@link Piwik\Plugin\ProcessedMetric}s for a DataTable.
@@ -1291,6 +1299,15 @@ class DataTable implements DataTableInterface, \IteratorAggregate, \ArrayAccess
             $subtableId = 0;
             throw new Exception("Maximum recursion level of " . self::$maximumDepthLevelAllowed . " reached. Maybe you have set a DataTable\Row with an associated DataTable belonging already to one of its parent tables?");
         }
+
+        // gather metadata before filters are called, so their metadata is not stored in serialized form
+        $metadata = $this->getAllTableMetadata();
+        foreach ($metadata as $key => $value) {
+            if (!is_scalar($value) && !is_string($value)) {
+                unset($metadata[$key]);
+            }
+        }
+
         if (!is_null($maximumRowsInDataTable)) {
             $this->filter('Truncate',
                 array($maximumRowsInDataTable - 1,
@@ -1341,6 +1358,16 @@ class DataTable implements DataTableInterface, \IteratorAggregate, \ArrayAccess
             $rows[self::ID_SUMMARY_ROW] = $this->summaryRow->export();
         }
 
+        if (!empty($metadata)) {
+            $metadataRow = new Row();
+            $metadataRow->setColumns($metadata);
+
+            // set the label so the row will be indexed correctly internally
+            $metadataRow->setColumn('label', self::LABEL_ARCHIVED_METADATA_ROW);
+
+            $rows[self::ID_ARCHIVED_METADATA_ROW] = $metadataRow->export();
+        }
+
         $aSerializedDataTable[$forcedId] = serialize($rows);
         unset($rows);
 
@@ -1402,6 +1429,13 @@ class DataTable implements DataTableInterface, \IteratorAggregate, \ArrayAccess
             unset($rows[self::ID_SUMMARY_ROW]);
         }
 
+        if (array_key_exists(self::ID_ARCHIVED_METADATA_ROW, $rows)) {
+            $metadata = $rows[self::ID_ARCHIVED_METADATA_ROW][Row::COLUMNS];
+            unset($metadata['label']);
+            $this->setAllTableMetadata($metadata);
+            unset($rows[self::ID_ARCHIVED_METADATA_ROW]);
+        }
+
         foreach ($rows as $id => $row) {
             if (isset($row->c)) {
                 $this->addRow(new Row($row->c)); // Pre Piwik 2.13
diff --git a/tests/PHPUnit/Unit/DataTableTest.php b/tests/PHPUnit/Unit/DataTableTest.php
index 424fce0186..fbc1f5adee 100644
--- a/tests/PHPUnit/Unit/DataTableTest.php
+++ b/tests/PHPUnit/Unit/DataTableTest.php
@@ -12,6 +12,7 @@ use Piwik\Common;
 use Piwik\DataTable\Manager;
 use Piwik\DataTable\Row;
 use Piwik\DataTable;
+use Piwik\Date;
 use Piwik\Timer;
 use Symfony\Component\VarDumper\Cloner\Data;
 
@@ -672,7 +673,9 @@ class DataTableTest extends \PHPUnit_Framework_TestCase
 
                 $subtableId = $row[Row::DATATABLE_ASSOCIATED];
 
-                if ($row[Row::COLUMNS]['label'] === DataTable::LABEL_SUMMARY_ROW) {
+                if ($row[Row::COLUMNS]['label'] === DataTable::LABEL_SUMMARY_ROW
+                    || $row[Row::COLUMNS]['label'] === DataTable::LABEL_ARCHIVED_METADATA_ROW
+                ) {
                     $this->assertNull($subtableId);
                 } else {
 
@@ -713,6 +716,38 @@ class DataTableTest extends \PHPUnit_Framework_TestCase
         ), $tables);
     }
 
+    public function test_serializationOfDataTableMetadata()
+    {
+        $table = new DataTable();
+        $table->addRow(new Row([
+            Row::COLUMNS => ['label' => 'abc', 'nb_visits' => 5],
+        ]));
+        $table->setAllTableMetadata([
+            'str' => 'str value',
+            'int' => 5,
+            'float' => 3.65,
+            'bool' => true,
+            'object' => Date::today(),
+        ]);
+
+        $serialized = $table->getSerialized();
+
+        $newTable = DataTable::fromSerializedArray(reset($serialized));
+
+        $this->assertEquals([
+            new Row([
+                Row::COLUMNS => ['label' => 'abc', 'nb_visits' => 5],
+            ]),
+        ], $newTable->getRows());
+
+        $this->assertEquals([
+            'str' => 'str value',
+            'int' => 5,
+            'float' => 3.65,
+            'bool' => true,
+        ], $newTable->getAllTableMetadata());
+    }
+
     private function addManyRows(DataTable $table, $numRows)
     {
         for ($i = 0; $i < $numRows; $i++) {