Personal Data Export

Nene\Func\PersonalDataExport is a GDPR Article 20-style personal data portability helper. It aggregates user data from multiple registered provider closures and assembles it into a portable JSON structure.

When to use

Use PersonalDataExport when you need to:

• Respond to user data portability requests (GDPR Article 20, CCPA)
• Build a "Download your data" feature
• Aggregate data spread across multiple tables into one JSON file
• Test data exports without coupling the aggregator to specific database schemas

API

use Nene\Func\PersonalDataExport;

Method	Description
register(string $section, callable $provider): static	Register a provider for a section. Returns $this for fluent chaining.
export(int\|string $userId): array	Run all providers and return the aggregated array.
exportJson(int\|string $userId, int $flags = …): string	Run all providers and return a JSON string.
sections(): array	Return registered section names in registration order (for tests).

Registering providers

Register one provider per logical data category at bootstrap or in a service initializer:

$export = new PersonalDataExport();

$export
    ->register('profile', function (int|string $userId) use ($pdo): array {
        $stmt = $pdo->prepare(
            'SELECT name, email, created_at FROM users WHERE id = ?'
        );
        $stmt->execute([$userId]);
        return $stmt->fetch(\PDO::FETCH_ASSOC) ?: [];
    })
    ->register('orders', function (int|string $userId) use ($pdo): array {
        $stmt = $pdo->prepare(
            'SELECT id, total, status, created_at FROM orders WHERE user_id = ?'
        );
        $stmt->execute([$userId]);
        return $stmt->fetchAll(\PDO::FETCH_ASSOC);
    })
    ->register('activity', function (int|string $userId) use ($pdo): array {
        $stmt = $pdo->prepare(
            'SELECT event, occurred_at FROM activity_log WHERE user_id = ? ORDER BY occurred_at DESC'
        );
        $stmt->execute([$userId]);
        return $stmt->fetchAll(\PDO::FETCH_ASSOC);
    });

• Providers fire in registration order.
• Registering the same section name twice overwrites the previous provider.
• The provider's return value can be any array shape — a flat record, a list of rows, or a nested structure.

Generating the export

// Structured array
$result = $export->export($userId);
// $result['exportedAt'] — ISO 8601 timestamp
// $result['userId']     — the requested user ID
// $result['data']       — section → data map

// JSON for download
$json = $export->exportJson($userId);
header('Content-Type: application/json');
header('Content-Disposition: attachment; filename="my-data.json"');
echo $json;

Output structure

{
  "exportedAt": "2026-05-27T12:00:00+00:00",
  "userId": 42,
  "data": {
    "profile": {
      "name": "Taro Yamada",
      "email": "taro@example.com",
      "created_at": "2024-01-15 09:23:00"
    },
    "orders": [
      { "id": 1, "total": 1500, "status": "completed" }
    ],
    "activity": [
      { "event": "login", "occurred_at": "2026-05-27 10:00:00" }
    ]
  }
}

Custom JSON flags

exportJson() defaults to JSON_PRETTY_PRINT | JSON_UNESCAPED_UNICODE. Pass custom flags for compact output or different encoding:

// Compact JSON
$json = $export->exportJson($userId, 0);

// Compact + Unicode-safe
$json = $export->exportJson($userId, JSON_UNESCAPED_UNICODE);

JSON_THROW_ON_ERROR is always added internally — encoding errors throw \JsonException.

Provider signature

Every provider receives one argument: the user ID passed to export() or exportJson().

$provider = function (int|string $userId): array {
    // fetch and return data for this user
    return [];
};

The user ID type is int|string to support both integer primary keys and UUID string identifiers.

Empty sections

A provider may return []. The section key is still included in the export with an empty array value. This makes the output schema predictable regardless of whether the user has data in that category.

Testing

Because providers are plain callables, no real database is needed in tests:

$export = new PersonalDataExport();

$export->register('profile', function (int|string $userId): array {
    return ['name' => 'Test User', 'userId' => $userId];
});

$result = $export->export(42);

self::assertSame(42, $result['userId']);
self::assertSame('Test User', $result['data']['profile']['name']);

Use sections() to assert provider registration without triggering data fetching:

self::assertSame(['profile', 'orders'], $export->sections());

Related

• Nene\Func\I18n — for localising the export filename or section labels.
• Nene\Func\EventDispatcher — emit a user.data-exported event after a successful export for audit logging.