yiisoft/yii2 · error · InvalidConfigException

The fileinfo PHP extension is not installed.

Error message

The fileinfo PHP extension is not installed.

What it means

Error "The fileinfo PHP extension is not installed." thrown in yiisoft/yii2.

Source

Thrown at framework/helpers/BaseFileHelper.php:167

     * This will be passed as the second parameter to [finfo_open()](https://www.php.net/manual/en/function.finfo-open.php)
     * when the `fileinfo` extension is installed. If the MIME type is being determined based via [[getMimeTypeByExtension()]]
     * and this is null, it will use the file specified by [[mimeMagicFile]].
     * @param bool $checkExtension whether to use the file extension to determine the MIME type in case
     * `finfo_open()` cannot determine it.
     * @return string|null the MIME type (e.g. `text/plain`). Null is returned if the MIME type cannot be determined.
     * @throws InvalidConfigException when the `fileinfo` PHP extension is not installed and `$checkExtension` is `false`.
     */
    public static function getMimeType($file, $magicFile = null, $checkExtension = true)
    {
        if ($magicFile !== null) {
            $magicFile = Yii::getAlias($magicFile);
        }
        if (!extension_loaded('fileinfo')) {
            if ($checkExtension) {
                return static::getMimeTypeByExtension($file, $magicFile);
            }

            throw new InvalidConfigException('The fileinfo PHP extension is not installed.');
        }

        $info = finfo_open(FILEINFO_MIME_TYPE, $magicFile);

        if ($info) {
            $result = finfo_file($info, $file);
            // @link https://wiki.php.net/rfc/deprecations_php_8_5#deprecate_finfo_close
            // @link https://github.com/php/php-src/commit/ccb716dcadf60d989db48e4d2963e14d7dc63df3
            if (PHP_VERSION_ID < 80500) {
                finfo_close($info);
            }

            if ($result !== false) {
                return $result;
            }
        }

        return $checkExtension ? static::getMimeTypeByExtension($file, $magicFile) : null;

View on GitHub (pinned to 66f00d18a2)

When it happens

Trigger: Thrown at framework/helpers/BaseFileHelper.php:167 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of yiisoft/yii2@66f00d18a2 (2026-08-17). Data as JSON: /api/errors/5e49b46252e7a55a. Report an issue: GitHub.