phacility/phabricator · error · PhutilArgumentUsageException

Output path already exists. Use "--overwrite" to overwrite i

Error message

Output path already exists. Use "--overwrite" to overwrite it.

What it means

The export workflow will not clobber an existing file unless told to. When the destination path exists (Filesystem::pathExists), --output is not stdout, and --overwrite was not passed, this usage exception is thrown. It protects existing data from being replaced by a re-run.

Source

Thrown at src/applications/transactions/bulk/management/PhabricatorBulkManagementExportWorkflow.php:101

          'Use "--output <path>" to specify an output file, or "--output -" '.
          'to print to stdout.'));
    }

    if ($output_path === '-') {
      $is_stdout = true;
    } else {
      $is_stdout = false;
    }

    if ($is_stdout && $is_overwrite) {
      throw new PhutilArgumentUsageException(
        pht(
          'Flag "--overwrite" has no effect when outputting to stdout.'));
    }

    if (!$is_overwrite) {
      if (!$is_stdout && Filesystem::pathExists($output_path)) {
        throw new PhutilArgumentUsageException(
          pht(
            'Output path already exists. Use "--overwrite" to overwrite '.
            'it.'));
      }
    }

    // If we have more than one query, execute the queries to figure out which
    // results they hit, then build a synthetic query for all those results
    // using the IDs.
    if (count($queries) > 1) {
      $saved_query = $this->newUnionQuery($engine, $queries);
    } else {
      $saved_query = head($queries);
    }

    $export_engine = id(new PhabricatorExportEngine())
      ->setViewer($viewer)
      ->setTitle(pht('Export'))

View on GitHub (pinned to 5720a38cfe)

Solutions

1. Add --overwrite to the command if replacing the file is intended.
2. Export to a fresh path, e.g. one containing a timestamp: --output tasks-$(date +%F).csv.
3. Remove or move the existing file before the export runs.

Example fix

# before
bin/bulk export --query all --output /tmp/tasks.csv
# after (if replacing the file is intended)
bin/bulk export --query all --output /tmp/tasks.csv --overwrite

if [[ -e "$DEST" && "$ALLOW_OVERWRITE" != 1 ]]; then
  echo "output already exists: $DEST" >&2; exit 2
fi

When it happens

Trigger: Running an export to a path that already exists from a previous run, without --overwrite. Also triggered when the path exists as a directory, since pathExists matches any filesystem entry.

Common situations: Repeated cron exports writing to a fixed filename; an earlier failed run left a partial file; shared mounts (NFS, docker volumes) where another process created the file.

Related errors

• Use "--output <path>" to specify an output file, or "--outpu
• Flag "--overwrite" has no effect when outputting to stdout.
• Specify one or more queries to export with "--query".
• No search engines match "%s". Available engines which suppor
• Multiple search engines match "%s": %s.

AI-assisted analysis of phacility/phabricator@5720a38cfe (2026-08-21). Data as JSON: /api/errors/95c66d0b189b3df5. Report an issue: GitHub.