Proyectos de Subversion Moodle

<?php

namespace Aws\Endpoint\UseDualstackEndpoint;

use Aws\AbstractConfigurationProvider;

use Aws\CacheInterface;

use Aws\ConfigurationProviderInterface;

use Aws\Endpoint\UseDualstackEndpoint\Exception\ConfigurationException;

use GuzzleHttp\Promise;

/**

 * A configuration provider is a function that returns a promise that is

 * fulfilled with a {@see \Aws\Endpoint\UseDualstackEndpoint\onfigurationInterface}

 * or rejected with an {@see \Aws\Endpoint\UseDualstackEndpoint\ConfigurationException}.

 *

 * <code>

 * use Aws\Endpoint\UseDualstackEndpoint\ConfigurationProvider;

 * $provider = ConfigurationProvider::defaultProvider();

 * // Returns a ConfigurationInterface or throws.

 * $config = $provider()->wait();

 * </code>

 *

 * Configuration providers can be composed to create configuration using

 * conditional logic that can create different configurations in different

 * environments. You can compose multiple providers into a single provider using

 * {@see Aws\Endpoint\UseDualstackEndpoint\ConfigurationProvider::chain}. This function

 * accepts providers as variadic arguments and returns a new function that will

 * invoke each provider until a successful configuration is returned.

 *

 * <code>

 * // First try an INI file at this location.

 * $a = ConfigurationProvider::ini(null, '/path/to/file.ini');

 * // Then try an INI file at this location.

 * $b = ConfigurationProvider::ini(null, '/path/to/other-file.ini');

 * // Then try loading from environment variables.

 * $c = ConfigurationProvider::env();

 * // Combine the three providers together.

 * $composed = ConfigurationProvider::chain($a, $b, $c);

 * // Returns a promise that is fulfilled with a configuration or throws.

 * $promise = $composed();

 * // Wait on the configuration to resolve.

 * $config = $promise->wait();

 * </code>

 */

class ConfigurationProvider extends AbstractConfigurationProvider

    implements ConfigurationProviderInterface

{

    const ENV_USE_DUAL_STACK_ENDPOINT = 'AWS_USE_DUALSTACK_ENDPOINT';

    const INI_USE_DUAL_STACK_ENDPOINT = 'use_dualstack_endpoint';

    public static $cacheKey = 'aws_cached_use_dualstack_endpoint_config';

    protected static $interfaceClass = ConfigurationInterface::class;

    protected static $exceptionClass = ConfigurationException::class;

    /**

     * Create a default config provider that first checks for environment

     * variables, then checks for a specified profile in the environment-defined

     * config file location (env variable is 'AWS_CONFIG_FILE', file location

     * defaults to ~/.aws/config), then checks for the "default" profile in the

     * environment-defined config file location, and failing those uses a default

     * fallback set of configuration options.

     *

     * This provider is automatically wrapped in a memoize function that caches

     * previously provided config options.

     *

     * @param array $config

     *

     * @return callable

     */

    public static function defaultProvider(array $config = [])

    {

        $region = $config['region'];

        $configProviders = [self::env($region)];

        if (

            !isset($config['use_aws_shared_config_files'])

            || $config['use_aws_shared_config_files'] != false

        ) {

            $configProviders[] = self::ini($region);

        }

        $configProviders[] = self::fallback($region);

        $memo = self::memoize(

            call_user_func_array([ConfigurationProvider::class, 'chain'], $configProviders)

        );

        if (isset($config['use_dual_stack_endpoint'])

            && $config['use_dual_stack_endpoint'] instanceof CacheInterface

        ) {

            return self::cache($memo, $config['use_dual_stack_endpoint'], self::$cacheKey);

        }

        return $memo;

    }

    /**

     * Provider that creates config from environment variables.

     *

     * @return callable

     */

    public static function env($region)

    {

        return function () use ($region) {

            // Use config from environment variables, if available

            $useDualstackEndpoint = getenv(self::ENV_USE_DUAL_STACK_ENDPOINT);

            if (!empty($useDualstackEndpoint)) {

                return Promise\Create::promiseFor(

                    new Configuration($useDualstackEndpoint, $region)

                );

            }

            return self::reject('Could not find environment variable config'

                . ' in ' . self::ENV_USE_DUAL_STACK_ENDPOINT);

        };

    }

    /**

     * Config provider that creates config using a config file whose location

     * is specified by an environment variable 'AWS_CONFIG_FILE', defaulting to

     * ~/.aws/config if not specified

     *

     * @param string|null $profile  Profile to use. If not specified will use

     *                              the "default" profile.

     * @param string|null $filename If provided, uses a custom filename rather

     *                              than looking in the default directory.

     *

     * @return callable

     */

    public static function ini($region, $profile = null, $filename = null)

    {

        $filename = $filename ?: (self::getDefaultConfigFilename());

        $profile = $profile ?: (getenv(self::ENV_PROFILE) ?: 'default');

        return function () use ($region, $profile, $filename) {

            if (!@is_readable($filename)) {

                return self::reject("Cannot read configuration from $filename");

            }

            // Use INI_SCANNER_NORMAL instead of INI_SCANNER_TYPED for PHP 5.5 compatibility

            $data = \Aws\parse_ini_file($filename, true, INI_SCANNER_NORMAL);

            if ($data === false) {

                return self::reject("Invalid config file: $filename");

            }

            if (!isset($data[$profile])) {

                return self::reject("'$profile' not found in config file");

            }

            if (!isset($data[$profile][self::INI_USE_DUAL_STACK_ENDPOINT])) {

                return self::reject("Required use dualstack endpoint config values

                    not present in INI profile '{$profile}' ({$filename})");

            }

            // INI_SCANNER_NORMAL parses false-y values as an empty string

            if ($data[$profile][self::INI_USE_DUAL_STACK_ENDPOINT] === "") {

                $data[$profile][self::INI_USE_DUAL_STACK_ENDPOINT] = false;

            }

            return Promise\Create::promiseFor(

                new Configuration($data[$profile][self::INI_USE_DUAL_STACK_ENDPOINT], $region)

            );

        };

    }

    /**

     * Fallback config options when other sources are not set.

     *

     * @return callable

     */

    public static function fallback($region)

    {

        return function () use ($region) {

            return Promise\Create::promiseFor(new Configuration(false, $region));

        };

    }

}