DotEnv.php

DotEnv.php

<?php

/**
 * Environment-specific configuration. This class was extracted directly from the CodeIgniter 4
 * framework and upgraded to use features from PHP >=8.0.0
 * 
 *
 * @link https://github.com/codeigniter4/CodeIgniter4/blob/develop/system/Config/DotEnv.php
 */
class DotEnv
{
    /**
     * The directory where the .env file can be located.
     *
     * @var string
     */
    protected string $path;

    //--------------------------------------------------------------------

    /**
     * Builds the path to our file.
     *
     * @param string $path
     * @param string $file
     */
    public function __construct(string $path, string $file = '.env')
    {
        $this->path = rtrim($path, DIRECTORY_SEPARATOR) . DIRECTORY_SEPARATOR . $file;
    }

    //--------------------------------------------------------------------

    /**
     * The main entry point, will load the .env file and process it
     * so that we end up with all settings in the PHP environment vars
     * (i.e. getenv(), $_ENV, and $_SERVER)
     *
     * @return boolean
     */
    public function load(): bool
    {
        // We don't want to enforce the presence of a .env file,
        // they should be optional.
        if ( ! is_file($this->path) ) {
            return false;
        }

        // Ensure file is readable
        if ( ! is_readable($this->path) ) {
            throw new \InvalidArgumentException("The .env file is not readable: {$this->path}");
        }

        $lines = file($this->path, FILE_IGNORE_NEW_LINES | FILE_SKIP_EMPTY_LINES);

        foreach ( $lines as $line ) {
            // Is it a comment?
            if ( str_starts_with(trim($line), '#') ) {
                continue;
            }

            // If there is an equal sign, then we know we
            // are assigning a variable.
            if ( str_contains($line, '=') ) {
                $this->setVariable($line);
            }
        }

        return true; // for success
    }

    //--------------------------------------------------------------------

    /**
     * Sets the variable into the environment. Will parse the string
     * first to look for {name}={value} pattern, ensure that nested
     * variables are handled, and strip it of single and double quotes.
     *
     * @param string $name
     * @param string $value
     */
    protected function setVariable(string $name, string $value = ''): void
    {
        [$name, $value] = $this->normaliseVariable($name, $value);

        if ( ! getenv($name, true) ) {
            putenv("$name=$value");
        }
        if ( empty($_ENV[ $name ]) ) {
            $_ENV[ $name ] = $value;
        }
        if ( empty($_SERVER[ $name ]) ) {
            $_SERVER[ $name ] = $value;
        }
    }

    //--------------------------------------------------------------------

    /**
     * Parses for assignment, cleans the $name and $value, and ensures
     * that nested variables are handled.
     *
     * @param string $name
     * @param string $value
     *
     * @return array
     */
    public function normaliseVariable(string $name, string $value = ''): array
    {
        // Split our compound string into it's parts.
        if ( str_contains($name, '=') ) {
            [$name, $value] = explode('=', $name, 2);
        }

        $name = trim($name);
        $value = trim($value);

        // Sanitize the name
        $name = str_replace(['export', '\'', '"'], '', $name);

        // Sanitize the value
        $value = $this->sanitizeValue($value);

        $value = $this->resolveNestedVariables($value);

        return [
            $name,
            $value,
        ];
    }

    //--------------------------------------------------------------------

    /**
     * Strips quotes from the environment variable value.
     *
     * This was borrowed from the excellent phpdotenv with very few changes.
     * https://github.com/vlucas/phpdotenv
     *
     * @param string $value
     *
     * @return string
     * @throws \InvalidArgumentException
     */
    protected function sanitizeValue(string $value): string
    {
        if ( ! $value ) {
            return $value;
        }

        // Does it begin with a quote?
        if ( strpbrk($value[ 0 ], '"\'') !== false ) {
            // value starts with a quote
            $quote = $value[ 0 ];
            $regexPattern = sprintf(
                '/^
                %1$s          # match a quote at the start of the value
                (             # capturing sub-pattern used
                              (?:          # we do not need to capture this
                               [^%1$s\\\\] # any character other than a quote or backslash
                               |\\\\\\\\   # or two backslashes together
                               |\\\\%1$s   # or an escaped quote e.g \"
                              )*           # as many characters that match the previous rules
                )             # end of the capturing sub-pattern
                %1$s          # and the closing quote
                .*$           # and discard any string after the closing quote
                /mx', $quote
            );
            $value = preg_replace($regexPattern, '$1', $value);
            $value = str_replace(["\\$quote", '\\\\'], [$quote, '\\'], $value);
        } else {
            $parts = explode(' #', $value, 2);

            $value = trim($parts[ 0 ]);

            // Unquoted values cannot contain whitespace
            if ( preg_match('/\s+/', $value) > 0 ) {
                throw new \InvalidArgumentException('.env values containing spaces must be surrounded by quotes.');
            }
        }

        return $value;
    }

    //--------------------------------------------------------------------

    /**
     *  Resolve the nested variables.
     *
     * Look for ${varname} patterns in the variable value and replace with an existing
     * environment variable.
     *
     * This was borrowed from the excellent phpdotenv with very few changes.
     * https://github.com/vlucas/phpdotenv
     *
     * @param $value
     *
     * @return string
     */
    protected function resolveNestedVariables(string $value): string
    {
        if ( str_contains($value, '$') ) {
            $loader = $this;

            $value = preg_replace_callback(
                '/\${([a-zA-Z0-9_]+)}/',
                static function ($matchedPatterns) use ($loader) {
                    $nestedVariable = $loader->getVariable($matchedPatterns[ 1 ]);

                    if ( is_null($nestedVariable) ) {
                        return $matchedPatterns[ 0 ];
                    }

                    return $nestedVariable;
                },
                $value
            );
        }

        return $value;
    }

    //--------------------------------------------------------------------

    /**
     * Search the different places for environment variables and return first value found.
     *
     * This was borrowed from the excellent phpdotenv with very few changes.
     * https://github.com/vlucas/phpdotenv
     *
     * @param string $name
     *
     * @return string|null
     */
    protected function getVariable(string $name): ?string
    {
        switch ( true ) {
            case array_key_exists($name, $_ENV):
                return $_ENV[ $name ];
            case array_key_exists($name, $_SERVER):
                return $_SERVER[ $name ];
            default:
                $value = getenv($name);

                // switch getenv default to null
                return $value === false ? null : $value;
        }
    }

    //--------------------------------------------------------------------
}

env.example

#--------------------------------------------------------------------
# Example Environment Configuration file
#
# This file can be used as a starting point for your own
# custom .env files, and contains most of the possible settings
# available in a default install.
#
# By default, all of the settings are commented out. If you want
# to override the setting, you must un-comment it by removing the '#'
# at the beginning of the line.
#--------------------------------------------------------------------


#--------------------------------------------------------------------
# APP CONFIG
#--------------------------------------------------------------------

# config.baseURL = 'http://change.me'

#--------------------------------------------------------------------
# DATABASE
#--------------------------------------------------------------------

# database.hostname = localhost
# database.database = database
# database.username = username
# database.password = password