phacility/phabricator · error · Exception

Trying to construct a dataset of type "%s", but this type is

Error message

Trying to construct a dataset of type "%s", but this type is unknown. Supported types are: %s.

What it means

PhabricatorChartDataset::newFromDictionary() rebuilds a chart dataset from a stored dictionary. After a PhutilTypeSpec::checkMap confirming 'type' is a string, it looks the type up in the registry built from PhabricatorChartDataset subclasses; an unregistered type raises this Exception, listing all supported type keys.

Source

Thrown at src/applications/fact/chart/PhabricatorChartDataset.php:43

    return id(new PhutilClassMapQuery())
      ->setAncestorClass(__CLASS__)
      ->setUniqueMethod('getDatasetTypeKey')
      ->execute();
  }

  final public static function newFromDictionary(array $map) {
    PhutilTypeSpec::checkMap(
      $map,
      array(
        'type' => 'string',
        'functions' => 'list<wild>',
      ));

    $types = self::getAllDatasetTypes();

    $dataset_type = $map['type'];
    if (!isset($types[$dataset_type])) {
      throw new Exception(
        pht(
          'Trying to construct a dataset of type "%s", but this type is '.
          'unknown. Supported types are: %s.',
          $dataset_type,
          implode(', ', array_keys($types))));
    }

    $dataset = id(clone $types[$dataset_type]);

    $functions = array();
    foreach ($map['functions'] as $map) {
      $functions[] = PhabricatorChartFunction::newFromDictionary($map);
    }
    $dataset->setFunctions($functions);

    return $dataset;
  }

View on GitHub (pinned to 5720a38cfe)

Solutions

1. Read the message: it enumerates every supported dataset type — pick one of those exact keys.
2. If the dictionary comes from a stored chart, rebuild/re-save the chart in the UI so it stores a current type.
3. If custom code builds the dictionary, dump PhabricatorChartDataset::getAllDatasetTypes() and align the key.
4. After a custom class rename, update or migrate stored chart data referencing the old key.

Example fix

// before
$dataset = PhabricatorChartDataset::newFromDictionary(array(
  'type' => 'my-dataset', // not registered -> Exception
  'functions' => $functions,
));

// after
$types = PhabricatorChartDataset::getAllDatasetTypes();
$type = isset($types['my-dataset']) ? 'my-dataset' : 'fact-count-dataset';
$dataset = PhabricatorChartDataset::newFromDictionary(array(
  'type' => $type,
  'functions' => $functions,
));

$types = PhabricatorChartDataset::getAllDatasetTypes();
if (!isset($types[$map['type']])) {
  // reject or substitute before calling newFromDictionary()
  throw new Exception('Unsupported dataset type: '.$map['type']);
}

When it happens

Trigger: Calling PhabricatorChartDataset::newFromDictionary(array('type' => ..., 'functions' => ...)) with a 'type' that is not a key of getAllDatasetTypes(). Typical with hand-built chart specifications, or rendering a stored chart whose dataset type class was removed or renamed between versions.

Common situations: Upgrading Phabricator and loading old chart data whose dataset class no longer exists; custom chart code constructing dictionaries with a guessed type name; copy-pasting a chart spec from documentation of a different version.

Related errors

• Attempting to build function "%s" from dictionary, but that
• Value for "fact-key" argument must be a string, got %s.
• Fact key "%s" is not a known fact key.
• Value for "function" argument must be a function definition,
• Value for "function" argument must be a natural list, not a

AI-assisted analysis of phacility/phabricator@5720a38cfe (2026-08-21). Data as JSON: /api/errors/791a8aed1c3ef007. Report an issue: GitHub.