Proyectos de Subversion Moodle

<?php

namespace Aws\Retry;

use Aws\AbstractConfigurationProvider;

use Aws\CacheInterface;

use Aws\ConfigurationProviderInterface;

use Aws\Retry\Exception\ConfigurationException;

use GuzzleHttp\Promise;

use GuzzleHttp\Promise\PromiseInterface;

/**

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

 * fulfilled with a {@see \Aws\Retry\ConfigurationInterface}

 * or rejected with an {@see \Aws\Retry\Exception\ConfigurationException}.

 *

 * <code>

 * use Aws\Sts\RegionalEndpoints\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\Retry\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 DEFAULT_MAX_ATTEMPTS = 3;

    const DEFAULT_MODE = 'legacy';

    const ENV_MAX_ATTEMPTS = 'AWS_MAX_ATTEMPTS';

    const ENV_MODE = 'AWS_RETRY_MODE';

    const ENV_PROFILE = 'AWS_PROFILE';

    const INI_MAX_ATTEMPTS = 'max_attempts';

    const INI_MODE = 'retry_mode';

    public static $cacheKey = 'aws_retries_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 = [])

    {

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

        if (

            !isset($config['use_aws_shared_config_files'])

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

        ) {

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

        }

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

        $memo = self::memoize(

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

        );

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

            && $config['retries'] instanceof CacheInterface

        ) {

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

        }

        return $memo;

    }

    /**

     * Provider that creates config from environment variables.

     *

     * @return callable

     */

    public static function env()

    {

        return function () {

            // Use config from environment variables, if available

            $mode = getenv(self::ENV_MODE);

            $maxAttempts = getenv(self::ENV_MAX_ATTEMPTS)

                ? getenv(self::ENV_MAX_ATTEMPTS)

                : self::DEFAULT_MAX_ATTEMPTS;

            if (!empty($mode)) {

                return Promise\Create::promiseFor(

                    new Configuration($mode, $maxAttempts)

                );

            }

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

                . ' in ' . self::ENV_MODE);

        };

    }

    /**

     * Fallback config options when other sources are not set.

     *

     * @return callable

     */

    public static function fallback()

    {

        return function () {

            return Promise\Create::promiseFor(

                new Configuration(self::DEFAULT_MODE, self::DEFAULT_MAX_ATTEMPTS)

            );

        };

    }

    /**

     * 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(

        $profile = null,

        $filename = null

    ) {

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

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

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

            if (!@is_readable($filename)) {

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

            }

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

            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_MODE])) {

                return self::reject("Required retry config values

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

            }

            $maxAttempts = isset($data[$profile][self::INI_MAX_ATTEMPTS])

                ? $data[$profile][self::INI_MAX_ATTEMPTS]

                : self::DEFAULT_MAX_ATTEMPTS;

            return Promise\Create::promiseFor(

                new Configuration(

                    $data[$profile][self::INI_MODE],

                    $maxAttempts

                )

            );

        };

    }

    /**

     * Unwraps a configuration object in whatever valid form it is in,

     * always returning a ConfigurationInterface object.

     *

     * @param  mixed $config

     * @return ConfigurationInterface

     * @throws \InvalidArgumentException

     */

    public static function unwrap($config)

    {

        if (is_callable($config)) {

            $config = $config();

        }

        if ($config instanceof PromiseInterface) {

            $config = $config->wait();

        }

        if ($config instanceof ConfigurationInterface) {

            return $config;

        }

        // An integer value for this config indicates the legacy 'retries'

        // config option, which is incremented to translate to max attempts

        if (is_int($config)) {

            return new Configuration('legacy', $config + 1);

        }

        if (is_array($config) && isset($config['mode'])) {

            $maxAttempts = isset($config['max_attempts'])

                ? $config['max_attempts']

                : self::DEFAULT_MAX_ATTEMPTS;

            return new Configuration($config['mode'], $maxAttempts);

        }

        throw new \InvalidArgumentException('Not a valid retry configuration'

            . ' argument.');

    }

}