octobercms/october · error · SystemException

[{$importFile}] {message}

Error message

[{$importFile}] {message}

What it means

ThemeSeed::importSeedData() runs the instructions in the theme's seeds/data.yaml and wraps any exception thrown during processing in a SystemException whose message is prefixed with the absolute YAML path. The prefix is context, not cause: the real failure (bad instruction, missing import file, model error) is the wrapped exception, available via getPrevious().

Source

Thrown at modules/cms/models/ThemeSeed.php:149

        BlueprintIndexer::instance()->setNotesOutput($this->getNotesOutput())->migrate();
    }

    /**
     * importSeedData
     */
    protected function importSeedData()
    {
        // Importing seed data
        $importFile = $this->themePath . '/seeds/data.yaml';
        if (File::isFile($importFile)) {
            $this->note('Importing Data');
            $instructions = Yaml::parseFile($importFile);

            try {
                $this->processSeedInstructions($instructions);
            }
            catch (Exception $ex) {
                throw new SystemException("[{$importFile}] " . $ex->getMessage(), 0, $ex);
            }
        }
    }

    /**
     * importSeedLang
     */
    protected function importSeedLang()
    {
        // Import language files
        $themeLangPath = $this->themePath . '/seeds/lang';
        $appLangPath = app_path('lang');
        if (File::isDirectory($themeLangPath)) {
            $this->note('Importing Translations');

            if (!File::exists($appLangPath)) {
                File::makeDirectory($appLangPath);
            }

View on GitHub (pinned to b608633a7e)

Solutions

  1. Read the message after the path and inspect $e->getPrevious() - it names the actual failing instruction and reason.
  2. Open the referenced seeds/data.yaml and fix the specific instruction flagged by the inner message (typically missing class/file/attributes, a non-loadable class, or a wrong file path).
  3. Re-run php artisan theme:seed <theme> after the fix; seed steps are idempotent for most importers via matches/attributes.
  4. If the inner error is a model import failure, correct the data file the instruction points at, not data.yaml itself.

Example fix

# before: only the wrapper is shown
# [themes/demo/seeds/data.yaml] Import file 'content/about.htm' does not exist.

// after: log the real cause when catching
catch (\October\Rain\Exception\SystemException $e) {
    $root = $e->getPrevious() ?: $e;
    \Log::error($root->getMessage());
}
# then fix the matching entry inside themes/demo/seeds/data.yaml
Defensive patterns

Strategy: try-catch

Try / catch

try {
    \Artisan::call('theme:seed', ['name' => $themeDir]);
} catch (\October\Rain\Exception\SystemException $e) {
    $root = $e->getPrevious() ?: $e;
    \Log::error('Seed failed: ' . $root->getMessage());
    // the '[path] ' prefix tells you WHICH yaml; the previous exception tells you WHY
}

Prevention

When it happens

Trigger: Running php artisan theme:seed (or theme activation seeding) on a theme whose seeds/data.yaml exists, where any processSeedInstruction() step throws - the catch rethrows as '[path/to/theme/seeds/data.yaml] original message'. Any of the instruction-level failures (missing keys, unknown class, missing file) or model import errors surface this way.

Common situations: Theme authors shipping seed data for the first time; seeding on an environment where a plugin required by an instruction is absent; YAML edits that dropped a required key; the underlying importer hitting validation errors on provided data.

Related errors

AI-assisted analysis of octobercms/october@b608633a7e (2026-08-21). Data as JSON: /api/errors/83ba3c55227485ea. Report an issue: GitHub.