installer.php

<?php
/**
 * This file is part of the teamneusta/hosts project.
 * Copyright (c) 2017 neusta GmbH | Ein team neusta Unternehmen
 * For the full copyright and license information, please view the LICENSE file that was distributed with this source code.
 * @license http://www.opensource.org/licenses/mit-license.html  MIT License
 *
 */

/**
 * originally authored by Kevin Herrera<kevin@herrera.io>
 */
namespace

{
    use Herrera\Version\Comparator;
    use Herrera\Version\Dumper;
    use Herrera\Version\Parser;

    $n = PHP_EOL;

    set_error_handler(
        function($code, $message) use ($n) {
            if ($code & error_reporting()) {
                echo "$n{$n}Error: $message$n$n";
                exit(1);
            }
        }
    );

    echo "Host Installer$n";
    echo "=============$n$n";

    echo "Environment Check$n";
    echo "-----------------$n$n";

    echo "\"-\" indicates success.$n";
    echo "\"*\" indicates error.$n$n";

    // check version
    check(
        'You have a supported version of PHP (>= 7.0.0).',
        'You need PHP 7.0.0 or greater.',
        function() {
            return version_compare(PHP_VERSION, '7.0.0', '>=');
        }
    );

    // check phar extension
    check(
        'You have the "phar" extension installed.',
        'You need to have the "phar" extension installed.',
        function() {
            return extension_loaded('phar');
        }
    );

    // check phar extension version
    check(
        'You have a supported version of the "phar" extension.',
        'You need a newer version of the "phar" extension (>=2.0).',
        function() {
            $phar = new ReflectionExtension('phar');

            return version_compare($phar->getVersion(), '2.0', '>=');
        }
    );

    // check openssl extension
    check(
        'You have the "openssl" extension installed.',
        'Notice: The "openssl" extension will be needed to sign with private keys.',
        function() {
            return extension_loaded('openssl');
        },
        false
    );

    // check detect unicode setting
    check(
        'The "detect_unicode" setting is off.',
        'The "detect_unicode" setting needs to be off.',
        function() {
            return (ini_get_bool('detect_unicode') === false);
        }
    );

    // check suhosin setting
    if (extension_loaded('suhosin')) {
        check(
            'The "phar" stream wrapper is allowed by suhosin.',
            'The "phar" stream wrapper is blocked by suhosin.',
            function() {
                $white = ini_get('suhosin.executor.include.whitelist');
                $black = ini_get('suhosin.executor.include.blacklist');

                if ((false === stripos($white, 'phar'))
                    || (false !== stripos($black, 'phar'))) {
                    return false;
                }

                return true;
            }
        );
    }

    // check allow url open setting
    check(
        'The "allow_url_fopen" setting is on.',
        'The "allow_url_fopen" setting needs to be on.',
        function() {
            return ini_get_bool('allow_url_fopen');
        }
    );

    echo "{$n}Everything seems good!$n$n";

    // Retrieve manifest
    echo " - Downloading manifest...$n";

    $manifest = file_get_contents('http://teamneusta.github.io/php-cli-hosts/manifest.json');

    echo " - Reading manifest...$n";

    $manifest = json_decode($manifest);
    $current = null;

    foreach ($manifest as $item) {
        $item->version = Parser::toVersion($item->version);

        if ($current
            && (Comparator::isGreaterThan($item->version, $current->version))) {
            $current = $item;
        }
    }

    if (!$item) {
        echo " x No application download was found.$n";
    }

    echo " - Downloading Host v", Dumper::toString($item->version), "...$n";

    file_put_contents($item->name, file_get_contents($item->url));

    echo " - Checking file checksum...$n";

    if ($item->sha1 !== sha1_file($item->name)) {
        unlink($item->name);

        echo " x The download was corrupted.$n";
    }

    echo " - Checking if valid Phar...$n";

    try {
        new Phar($item->name);
    } catch (Exception $e) {
        echo " x The Phar is not valid.\n\n";

        throw $e;
    }

    echo " - Making Host executable...$n";

    if (@chmod($item->name, 0755) === false) {
        throw new \RuntimeException('Permissions on ' . $item->name . ' could not be changed.');
    }

    echo "{$n}Host installed!$n";

    /**
     * Checks a condition, outputs a message, and exits if failed.
     *
     * @param string   $success   The success message.
     * @param string   $failure   The failure message.
     * @param callable $condition The condition to check.
     * @param boolean  $exit      Exit on failure?
     */
    function check($success, $failure, $condition, $exit = true)
    {
        global $n;

        if ($condition()) {
            echo ' - ', $success, $n;
        } else {
            echo ' * ', $failure, $n;

            if ($exit) {
                exit(1);
            }
        }
    }

    /**
     * @param string $varname
     *
     * @return bool
     */
    function ini_get_bool($varname) {
        return \filter_var(\ini_get($varname), FILTER_VALIDATE_BOOLEAN);
    }
}

namespace Herrera\Version\Exception

{
    use Exception;

    /**
     * Throw if an invalid version string representation is used.
     *
     * @author Kevin Herrera <kevin@herrera.io>
     */
    class InvalidStringRepresentationException extends VersionException
    {
        /**
         * The invalid string representation.
         *
         * @var string
         */
        private $version;

        /**
         * Sets the invalid string representation.
         *
         * @param string $version The string representation.
         */
        public function __construct($version)
        {
            parent::__construct(
                sprintf(
                    'The version string representation "%s" is invalid.',
                    $version
                )
            );

            $this->version = $version;
        }

        /**
         * Returns the invalid string representation.
         *
         * @return string The invalid string representation.
         */
        public function getVersion()
        {
            return $this->version;
        }
    }

    /**
     * The base library exception class.
     *
     * @author Kevin Herrera <kevin@herrera.io>
     */
    class VersionException extends Exception
    {
    }
}

namespace Herrera\Version

{
    use Herrera\Version\Exception\InvalidStringRepresentationException;

    /**
     * Compares two Version instances.
     *
     * @author Kevin Herrera <kevin@herrera.io>
     */
    class Comparator
    {
        /**
         * The version is equal to another.
         */
        const EQUAL_TO = 0;

        /**
         * The version is greater than another.
         */
        const GREATER_THAN = 1;

        /**
         * The version is less than another.
         */
        const LESS_THAN = -1;

        /**
         * Compares one version with another.
         *
         * @param Version $left The left version to compare.
         * @param Version $right The right version to compare.
         *
         * @return integer Returns Comparator::EQUAL_TO if the two versions are
         * equal. If the left version is less than the right
         * version, Comparator::LESS_THAN is returned. If the left
         * version is greater than the right version,
         * Comparator::GREATER_THAN is returned.
         */
        public static function compareTo(Version $left, Version $right)
        {
            switch (true) {
                case ($left->getMajor() < $right->getMajor()):
                    return self::LESS_THAN;
                case ($left->getMajor() > $right->getMajor()):
                    return self::GREATER_THAN;
                case ($left->getMinor() > $right->getMinor()):
                    return self::GREATER_THAN;
                case ($left->getMinor() < $right->getMinor()):
                    return self::LESS_THAN;
                case ($left->getPatch() > $right->getPatch()):
                    return self::GREATER_THAN;
                case ($left->getPatch() < $right->getPatch()):
                    return self::LESS_THAN;
                // @codeCoverageIgnoreStart
            }
            // @codeCoverageIgnoreEnd

            return self::compareIdentifiers(
                $left->getPreRelease(),
                $right->getPreRelease()
            );
        }

        /**
         * Checks if the left version is equal to the right.
         *
         * @param Version $left The left version to compare.
         * @param Version $right The right version to compare.
         *
         * @return boolean TRUE if the left version is equal to the right, FALSE
         * if not.
         */
        public static function isEqualTo(Version $left, Version $right)
        {
            return (self::EQUAL_TO === self::compareTo($left, $right));
        }

        /**
         * Checks if the left version is greater than the right.
         *
         * @param Version $left The left version to compare.
         * @param Version $right The right version to compare.
         *
         * @return boolean TRUE if the left version is greater than the right,
         * FALSE if not.
         */
        public static function isGreaterThan(Version $left, Version $right)
        {
            return (self::GREATER_THAN === self::compareTo($left, $right));
        }

        /**
         * Checks if the left version is less than the right.
         *
         * @param Version $left The left version to compare.
         * @param Version $right The right version to compare.
         *
         * @return boolean TRUE if the left version is less than the right,
         * FALSE if not.
         */
        public static function isLessThan(Version $left, Version $right)
        {
            return (self::LESS_THAN === self::compareTo($left, $right));
        }

        /**
         * Compares the identifier components of the left and right versions.
         *
         * @param array $left The left identifiers.
         * @param array $right The right identifiers.
         *
         * @return integer Returns Comparator::EQUAL_TO if the two identifiers are
         * equal. If the left identifiers is less than the right
         * identifiers, Comparator::LESS_THAN is returned. If the
         * left identifiers is greater than the right identifiers,
         * Comparator::GREATER_THAN is returned.
         */
        public static function compareIdentifiers(array $left, array $right)
        {
            if (!empty($left) && empty($right)) {
                return self::LESS_THAN;
            } elseif (empty($left) && !empty($right)) {
                return self::GREATER_THAN;
            }

            $l = $left;
            $r = $right;
            $x = self::GREATER_THAN;
            $y = self::LESS_THAN;

            if (count($l) < count($r)) {
                $l = $right;
                $r = $left;
                $x = self::LESS_THAN;
                $y = self::GREATER_THAN;
            }

            foreach (array_keys($l) as $i) {
                if (!isset($r[$i])) {
                    return $x;
                }

                if ($l[$i] === $r[$i]) {
                    continue;
                }

                if (true === ($li = (false != preg_match('/^\d+$/', $l[$i])))) {
                    $l[$i] = intval($l[$i]);
                }

                if (true === ($ri = (false != preg_match('/^\d+$/', $r[$i])))) {
                    $r[$i] = intval($r[$i]);
                }

                if ($li && $ri) {
                    return ($l[$i] > $r[$i]) ? $x : $y;
                } elseif (!$li && $ri) {
                    return $x;
                } elseif ($li && !$ri) {
                    return $y;
                }

                return strcmp($l[$i], $r[$i]);
            }

            return self::EQUAL_TO;
        }
    }

    /**
     * Dumps the Version instance to a variety of formats.
     *
     * @author Kevin Herrera <kevin@herrera.io>
     */
    class Dumper
    {
        /**
         * Returns the components of a Version instance.
         *
         * @param Version $version A version.
         *
         * @return array The components.
         */
        public static function toComponents(Version $version)
        {
            return array(
                Parser::MAJOR => $version->getMajor(),
                Parser::MINOR => $version->getMinor(),
                Parser::PATCH => $version->getPatch(),
                Parser::PRE_RELEASE => $version->getPreRelease(),
                Parser::BUILD => $version->getBuild()
            );
        }

        /**
         * Returns the string representation of a Version instance.
         *
         * @param Version $version A version.
         *
         * @return string The string representation.
         */
        public static function toString(Version $version)
        {
            return sprintf(
                '%d.%d.%d%s%s',
                $version->getMajor(),
                $version->getMinor(),
                $version->getPatch(),
                $version->getPreRelease()
                    ? '-' . join('.', $version->getPreRelease())
                    : '',
                $version->getBuild()
                    ? '+' . join('.', $version->getBuild())
                    : ''
            );
        }
    }

    /**
     * Parses the string representation of a version number.
     *
     * @author Kevin Herrera <kevin@herrera.io>
     */
    class Parser
    {
        /**
         * The build metadata component.
         */
        const BUILD = 'build';

        /**
         * The major version number component.
         */
        const MAJOR = 'major';

        /**
         * The minor version number component.
         */
        const MINOR = 'minor';

        /**
         * The patch version number component.
         */
        const PATCH = 'patch';

        /**
         * The pre-release version number component.
         */
        const PRE_RELEASE = 'pre';

        /**
         * Returns a Version builder for the string representation.
         *
         * @param string $version The string representation.
         *
         * @return Builder A Version builder.
         */
        public static function toBuilder($version)
        {
            return Builder::create()->importComponents(
                self::toComponents($version)
            );
        }

        /**
         * Returns the components of the string representation.
         *
         * @param string $version The string representation.
         *
         * @return array The components of the version.
         *
         * @throws InvalidStringRepresentationException If the string representation
         * is invalid.
         */
        public static function toComponents($version)
        {
            if (!Validator::isVersion($version)) {
                throw new InvalidStringRepresentationException($version);
            }

            if (false !== strpos($version, '+')) {
                list($version, $build) = explode('+', $version);

                $build = explode('.', $build);
            }

            if (false !== strpos($version, '-')) {
                list($version, $pre) = explode('-', $version);

                $pre = explode('.', $pre);
            }

            list(
                $major,
                $minor,
                $patch
                ) = explode('.', $version);

            return array(
                self::MAJOR => intval($major),
                self::MINOR => intval($minor),
                self::PATCH => intval($patch),
                self::PRE_RELEASE => isset($pre) ? $pre : array(),
                self::BUILD => isset($build) ? $build : array(),
            );
        }

        /**
         * Returns a Version instance for the string representation.
         *
         * @param string $version The string representation.
         *
         * @return Version A Version instance.
         */
        public static function toVersion($version)
        {
            $components = self::toComponents($version);

            return new Version(
                $components['major'],
                $components['minor'],
                $components['patch'],
                $components['pre'],
                $components['build']
            );
        }
    }

    /**
     * Validates version information.
     *
     * @author Kevin Herrera <kevin@herrera.io>
     */
    class Validator
    {
        /**
         * The regular expression for a valid identifier.
         */
        const IDENTIFIER_REGEX = '/^[0-9A-Za-z\-]+$/';

        /**
         * The regular expression for a valid semantic version number.
         */
        const VERSION_REGEX = '/^\d+\.\d+\.\d+(?:-([0-9A-Za-z-]+(?:\.[0-9A-Za-z-]+)*))?(?:\+([0-9A-Za-z-]+(?:\.[0-9A-Za-z-]+)*))?$/';

        /**
         * Checks if a identifier is valid.
         *
         * @param string $identifier A identifier.
         *
         * @return boolean TRUE if the identifier is valid, FALSE If not.
         */
        public static function isIdentifier($identifier)
        {
            return (true == preg_match(self::IDENTIFIER_REGEX, $identifier));
        }

        /**
         * Checks if a number is a valid version number.
         *
         * @param integer $number A number.
         *
         * @return boolean TRUE if the number is valid, FALSE If not.
         */
        public static function isNumber($number)
        {
            return (true == preg_match('/^\d+$/', $number));
        }

        /**
         * Checks if the string representation of a version number is valid.
         *
         * @param string $version The string representation.
         *
         * @return boolean TRUE if the string representation is valid, FALSE if not.
         */
        public static function isVersion($version)
        {
            return (true == preg_match(self::VERSION_REGEX, $version));
        }
    }

    /**
     * Stores and returns the version information.
     *
     * @author Kevin Herrera <kevin@herrera.io>
     */
    class Version
    {
        /**
         * The build metadata identifiers.
         *
         * @var array
         */
        protected $build;

        /**
         * The major version number.
         *
         * @var integer
         */
        protected $major;

        /**
         * The minor version number.
         *
         * @var integer
         */
        protected $minor;

        /**
         * The patch version number.
         *
         * @var integer
         */
        protected $patch;

        /**
         * The pre-release version identifiers.
         *
         * @var array
         */
        protected $preRelease;

        /**
         * Sets the version information.
         *
         * @param integer $major The major version number.
         * @param integer $minor The minor version number.
         * @param integer $patch The patch version number.
         * @param array $pre The pre-release version identifiers.
         * @param array $build The build metadata identifiers.
         */
        public function __construct(
            $major = 0,
            $minor = 0,
            $patch = 0,
            array $pre = array(),
            array $build = array()
        ) {
            $this->build = $build;
            $this->major = $major;
            $this->minor = $minor;
            $this->patch = $patch;
            $this->preRelease = $pre;
        }

        /**
         * Returns the build metadata identifiers.
         *
         * @return array The build metadata identifiers.
         */
        public function getBuild()
        {
            return $this->build;
        }

        /**
         * Returns the major version number.
         *
         * @return integer The major version number.
         */
        public function getMajor()
        {
            return $this->major;
        }

        /**
         * Returns the minor version number.
         *
         * @return integer The minor version number.
         */
        public function getMinor()
        {
            return $this->minor;
        }

        /**
         * Returns the patch version number.
         *
         * @return integer The patch version number.
         */
        public function getPatch()
        {
            return $this->patch;
        }

        /**
         * Returns the pre-release version identifiers.
         *
         * @return array The pre-release version identifiers.
         */
        public function getPreRelease()
        {
            return $this->preRelease;
        }
    }
}