Proyectos de Subversion Moodle

<?php

namespace Aws;

use Aws\Api\ApiProvider;

use Aws\Api\Service;

use Aws\Api\Validator;

use Aws\Auth\AuthResolver;

use Aws\Auth\AuthSchemeResolver;

use Aws\Auth\AuthSchemeResolverInterface;

use Aws\ClientSideMonitoring\ApiCallAttemptMonitoringMiddleware;

use Aws\ClientSideMonitoring\ApiCallMonitoringMiddleware;

use Aws\ClientSideMonitoring\Configuration;

use Aws\Configuration\ConfigurationResolver;

use Aws\Credentials\CredentialProvider;

use Aws\Credentials\Credentials;

use Aws\Credentials\CredentialsInterface;

use Aws\DefaultsMode\ConfigurationInterface as ConfigModeInterface;

use Aws\DefaultsMode\ConfigurationProvider as ConfigModeProvider;

use Aws\Endpoint\EndpointProvider;

use Aws\Endpoint\PartitionEndpointProvider;

use Aws\Endpoint\UseDualstackEndpoint\Configuration as UseDualStackEndpointConfiguration;

use Aws\Endpoint\UseDualstackEndpoint\ConfigurationInterface as UseDualStackEndpointConfigurationInterface;

use Aws\Endpoint\UseDualstackEndpoint\ConfigurationProvider as UseDualStackConfigProvider;

use Aws\Endpoint\UseFipsEndpoint\Configuration as UseFipsEndpointConfiguration;

use Aws\Endpoint\UseFipsEndpoint\ConfigurationInterface as UseFipsEndpointConfigurationInterface;

use Aws\Endpoint\UseFipsEndpoint\ConfigurationProvider as UseFipsConfigProvider;

use Aws\EndpointDiscovery\ConfigurationInterface;

use Aws\EndpointDiscovery\ConfigurationProvider;

use Aws\EndpointV2\EndpointDefinitionProvider;

use Aws\Exception\AwsException;

use Aws\Exception\InvalidRegionException;

use Aws\Retry\ConfigurationInterface as RetryConfigInterface;

use Aws\Retry\ConfigurationProvider as RetryConfigProvider;

use Aws\Signature\SignatureProvider;

use Aws\Token\Token;

use Aws\Token\TokenInterface;

use Aws\Token\TokenProvider;

use GuzzleHttp\Promise\PromiseInterface;

use InvalidArgumentException as IAE;

use Psr\Http\Message\RequestInterface;

/**

 * @internal Resolves a hash of client arguments to construct a client.

 */

class ClientResolver

{

    /** @var array */

    private $argDefinitions;

    /**

     * When using this option as default please make sure that, your config

     * has at least one data type defined in `valid` otherwise it will be

     * defaulted to `string`. Also, the default value will be the falsy value

     * based on the resolved data type. For example, the default for `string`

     * will be `''` and for bool will be `false`.

     *

     * @var string

     */

    const DEFAULT_FROM_ENV_INI = [

        __CLASS__,

        '_resolve_from_env_ini'

    ];

    /** @var array Map of types to a corresponding function */

    private static $typeMap = [

        'resource' => 'is_resource',

        'callable' => 'is_callable',

        'int'      => 'is_int',

        'bool'     => 'is_bool',

        'boolean'  => 'is_bool',

        'string'   => 'is_string',

        'object'   => 'is_object',

        'array'    => 'is_array',

    ];

    private static $defaultArgs = [

        'service' => [

            'type'     => 'value',

            'valid'    => ['string'],

            'doc'      => 'Name of the service to utilize. This value will be supplied by default when using one of the SDK clients (e.g., Aws\\S3\\S3Client).',

            'required' => true,

            'internal' => true

        ],

        'exception_class' => [

            'type'     => 'value',

            'valid'    => ['string'],

            'doc'      => 'Exception class to create when an error occurs.',

            'default'  => AwsException::class,

            'internal' => true

        ],

        'scheme' => [

            'type'     => 'value',

            'valid'    => ['string'],

            'default'  => 'https',

            'doc'      => 'URI scheme to use when connecting connect. The SDK will utilize "https" endpoints (i.e., utilize SSL/TLS connections) by default. You can attempt to connect to a service over an unencrypted "http" endpoint by setting ``scheme`` to "http".',

        ],

        'disable_host_prefix_injection' => [

            'type'      => 'value',

            'valid'     => ['bool'],

            'doc'       => 'Set to true to disable host prefix injection logic for services that use it. This disables the entire prefix injection, including the portions supplied by user-defined parameters. Setting this flag will have no effect on services that do not use host prefix injection.',

            'default'   => false,

        ],

        'ignore_configured_endpoint_urls' => [

            'type'      => 'value',

            'valid'     => ['bool'],

            'doc'       => 'Set to true to disable endpoint urls configured using `AWS_ENDPOINT_URL` and `endpoint_url` shared config option.',

            'fn'        => [__CLASS__, '_apply_ignore_configured_endpoint_urls'],

            'default'   => self::DEFAULT_FROM_ENV_INI,

        ],

        'endpoint' => [

            'type'  => 'value',

            'valid' => ['string'],

            'doc'   => 'The full URI of the webservice. This is only required when connecting to a custom endpoint (e.g., a local version of S3).',

            'fn'    => [__CLASS__, '_apply_endpoint'],

            'default'   => [__CLASS__, '_default_endpoint']

        ],

        'region' => [

            'type'     => 'value',

            'valid'    => ['string'],

            'doc'      => 'Region to connect to. See http://docs.aws.amazon.com/general/latest/gr/rande.html for a list of available regions.',

            'fn'       => [__CLASS__, '_apply_region'],

            'default'  => self::DEFAULT_FROM_ENV_INI

        ],

        'version' => [

            'type'     => 'value',

            'valid'    => ['string'],

            'doc'      => 'The version of the webservice to utilize (e.g., 2006-03-01).',

            'default' => 'latest',

        ],

        'signature_provider' => [

            'type'    => 'value',

            'valid'   => ['callable'],

            'doc'     => 'A callable that accepts a signature version name (e.g., "v4"), a service name, and region, and  returns a SignatureInterface object or null. This provider is used to create signers utilized by the client. See Aws\\Signature\\SignatureProvider for a list of built-in providers',

            'default' => [__CLASS__, '_default_signature_provider'],

        ],

        'api_provider' => [

            'type'     => 'value',

            'valid'    => ['callable'],

            'doc'      => 'An optional PHP callable that accepts a type, service, and version argument, and returns an array of corresponding configuration data. The type value can be one of api, waiter, or paginator.',

            'fn'       => [__CLASS__, '_apply_api_provider'],

            'default'  => [ApiProvider::class, 'defaultProvider'],

        ],

        'configuration_mode' => [

            'type'    => 'value',

            'valid'   => [ConfigModeInterface::class, CacheInterface::class, 'string', 'closure'],

            'doc'     => "Sets the default configuration mode. Otherwise provide an instance of Aws\DefaultsMode\ConfigurationInterface, an instance of  Aws\CacheInterface, or a string containing a valid mode",

            'fn'      => [__CLASS__, '_apply_defaults'],

            'default' => [ConfigModeProvider::class, 'defaultProvider']

        ],

        'use_fips_endpoint' => [

            'type'      => 'value',

            'valid'     => ['bool', UseFipsEndpointConfiguration::class, CacheInterface::class, 'callable'],

            'doc'       => 'Set to true to enable the use of FIPS pseudo regions',

            'fn'        => [__CLASS__, '_apply_use_fips_endpoint'],

            'default'   => [__CLASS__, '_default_use_fips_endpoint'],

        ],

        'use_dual_stack_endpoint' => [

            'type'      => 'value',

            'valid'     => ['bool', UseDualStackEndpointConfiguration::class, CacheInterface::class, 'callable'],

            'doc'       => 'Set to true to enable the use of dual-stack endpoints',

            'fn'        => [__CLASS__, '_apply_use_dual_stack_endpoint'],

            'default'   => [__CLASS__, '_default_use_dual_stack_endpoint'],

        ],

        'endpoint_provider' => [

            'type'     => 'value',

            'valid'    => ['callable', EndpointV2\EndpointProviderV2::class],

            'fn'       => [__CLASS__, '_apply_endpoint_provider'],

            'doc'      => 'An optional PHP callable that accepts a hash of options including a "service" and "region" key and returns NULL or a hash of endpoint data, of which the "endpoint" key is required. See Aws\\Endpoint\\EndpointProvider for a list of built-in providers.',

            'default'  => [__CLASS__, '_default_endpoint_provider'],

        ],

        'serializer' => [

            'default'   => [__CLASS__, '_default_serializer'],

            'fn'        => [__CLASS__, '_apply_serializer'],

            'internal'  => true,

            'type'      => 'value',

            'valid'     => ['callable'],

        ],

        'signature_version' => [

            'type'    => 'config',

            'valid'   => ['string'],

            'doc'     => 'A string representing a custom signature version to use with a service (e.g., v4). Note that per/operation signature version MAY override this requested signature version.',

            'default' => [__CLASS__, '_default_signature_version'],

        ],

        'signing_name' => [

            'type'    => 'config',

            'valid'   => ['string'],

            'doc'     => 'A string representing a custom service name to be used when calculating a request signature.',

            'default' => [__CLASS__, '_default_signing_name'],

        ],

        'signing_region' => [

            'type'    => 'config',

            'valid'   => ['string'],

            'doc'     => 'A string representing a custom region name to be used when calculating a request signature.',

            'default' => [__CLASS__, '_default_signing_region'],

        ],

        'profile' => [

            'type'  => 'config',

            'valid' => ['string'],

            'doc'   => 'Allows you to specify which profile to use when credentials are created from the AWS credentials file in your HOME directory. This setting overrides the AWS_PROFILE environment variable. Note: Specifying "profile" will cause the "credentials" and "use_aws_shared_config_files" keys to be ignored.',

            'fn'    => [__CLASS__, '_apply_profile'],

        ],

        'credentials' => [

            'type'    => 'value',

            'valid'   => [CredentialsInterface::class, CacheInterface::class, 'array', 'bool', 'callable'],

            'doc'     => 'Specifies the credentials used to sign requests. Provide an Aws\Credentials\CredentialsInterface object, an associative array of "key", "secret", and an optional "token" key, `false` to use null credentials, or a callable credentials provider used to create credentials or return null. See Aws\\Credentials\\CredentialProvider for a list of built-in credentials providers. If no credentials are provided, the SDK will attempt to load them from the environment.',

            'fn'      => [__CLASS__, '_apply_credentials'],

            'default' => [__CLASS__, '_default_credential_provider'],

        ],

        'token' => [

            'type'    => 'value',

            'valid'   => [TokenInterface::class, CacheInterface::class, 'array', 'bool', 'callable'],

            'doc'     => 'Specifies the token used to authorize requests. Provide an Aws\Token\TokenInterface object, an associative array of "token", and an optional "expiration" key, `false` to use a null token, or a callable token provider used to fetch a token or return null. See Aws\\Token\\TokenProvider for a list of built-in credentials providers. If no token is provided, the SDK will attempt to load one from the environment.',

            'fn'      => [__CLASS__, '_apply_token'],

            'default' => [__CLASS__, '_default_token_provider'],

        ],

        'auth_scheme_resolver' => [

            'type'    => 'value',

            'valid'   => [AuthSchemeResolverInterface::class],

            'doc'     => 'An instance of Aws\Auth\AuthSchemeResolverInterface which selects a modeled auth scheme and returns a signature version',

            'default' => [__CLASS__, '_default_auth_scheme_resolver'],

        ],

        'endpoint_discovery' => [

            'type'     => 'value',

            'valid'    => [ConfigurationInterface::class, CacheInterface::class, 'array', 'callable'],

            'doc'      => 'Specifies settings for endpoint discovery. Provide an instance of Aws\EndpointDiscovery\ConfigurationInterface, an instance Aws\CacheInterface, a callable that provides a promise for a Configuration object, or an associative array with the following keys: enabled: (bool) Set to true to enable endpoint discovery, false to explicitly disable it. Defaults to false; cache_limit: (int) The maximum number of keys in the endpoints cache. Defaults to 1000.',

            'fn'       => [__CLASS__, '_apply_endpoint_discovery'],

            'default'  => [__CLASS__, '_default_endpoint_discovery_provider']

        ],

        'stats' => [

            'type'  => 'value',

            'valid' => ['bool', 'array'],

            'default' => false,

            'doc'   => 'Set to true to gather transfer statistics on requests sent. Alternatively, you can provide an associative array with the following keys: retries: (bool) Set to false to disable reporting on retries attempted; http: (bool) Set to true to enable collecting statistics from lower level HTTP adapters (e.g., values returned in GuzzleHttp\TransferStats). HTTP handlers must support an http_stats_receiver option for this to have an effect; timer: (bool) Set to true to enable a command timer that reports the total wall clock time spent on an operation in seconds.',

            'fn'    => [__CLASS__, '_apply_stats'],

        ],

        'retries' => [

            'type'    => 'value',

            'valid'   => ['int', RetryConfigInterface::class, CacheInterface::class, 'callable', 'array'],

            'doc'     => "Configures the retry mode and maximum number of allowed retries for a client (pass 0 to disable retries). Provide an integer for 'legacy' mode with the specified number of retries. Otherwise provide an instance of Aws\Retry\ConfigurationInterface, an instance of  Aws\CacheInterface, a callable function, or an array with the following keys: mode: (string) Set to 'legacy', 'standard' (uses retry quota management), or 'adapative' (an experimental mode that adds client-side rate limiting to standard mode); max_attempts: (int) The maximum number of attempts for a given request. ",

            'fn'      => [__CLASS__, '_apply_retries'],

            'default' => [RetryConfigProvider::class, 'defaultProvider']

        ],

        'validate' => [

            'type'    => 'value',

            'valid'   => ['bool', 'array'],

            'default' => true,

            'doc'     => 'Set to false to disable client-side parameter validation. Set to true to utilize default validation constraints. Set to an associative array of validation options to enable specific validation constraints.',

            'fn'      => [__CLASS__, '_apply_validate'],

        ],

        'debug' => [

            'type'  => 'value',

            'valid' => ['bool', 'array'],

            'doc'   => 'Set to true to display debug information when sending requests. Alternatively, you can provide an associative array with the following keys: logfn: (callable) Function that is invoked with log messages; stream_size: (int) When the size of a stream is greater than this number, the stream data will not be logged (set to "0" to not log any stream data); scrub_auth: (bool) Set to false to disable the scrubbing of auth data from the logged messages; http: (bool) Set to false to disable the "debug" feature of lower level HTTP adapters (e.g., verbose curl output).',

            'fn'    => [__CLASS__, '_apply_debug'],

        ],

        'disable_request_compression' => [

            'type'      => 'value',

            'valid'     => ['bool', 'callable'],

            'doc'       => 'Set to true to disable request compression for supported operations',

            'fn'        => [__CLASS__, '_apply_disable_request_compression'],

            'default'   => self::DEFAULT_FROM_ENV_INI,

        ],

        'request_min_compression_size_bytes' => [

            'type'      => 'value',

            'valid'     => ['int', 'callable'],

            'doc'       => 'Set to a value between between 0 and 10485760 bytes, inclusive. This value will be ignored if `disable_request_compression` is set to `true`',

            'fn'        => [__CLASS__, '_apply_min_compression_size'],

            'default'   => [__CLASS__, '_default_min_compression_size'],

        ],

        'csm' => [

            'type'     => 'value',

            'valid'    => [\Aws\ClientSideMonitoring\ConfigurationInterface::class, 'callable', 'array', 'bool'],

            'doc'      => 'CSM options for the client. Provides a callable wrapping a promise, a boolean "false", an instance of ConfigurationInterface, or an associative array of "enabled", "host", "port", and "client_id".',

            'fn'       => [__CLASS__, '_apply_csm'],

            'default'  => [\Aws\ClientSideMonitoring\ConfigurationProvider::class, 'defaultProvider']

        ],

        'http' => [

            'type'    => 'value',

            'valid'   => ['array'],

            'default' => [],

            'doc'     => 'Set to an array of SDK request options to apply to each request (e.g., proxy, verify, etc.).',

        ],

        'http_handler' => [

            'type'    => 'value',

            'valid'   => ['callable'],

            'doc'     => 'An HTTP handler is a function that accepts a PSR-7 request object and returns a promise that is fulfilled with a PSR-7 response object or rejected with an array of exception data. NOTE: This option supersedes any provided "handler" option.',

            'fn'      => [__CLASS__, '_apply_http_handler']

        ],

        'handler' => [

            'type'     => 'value',

            'valid'    => ['callable'],

            'doc'      => 'A handler that accepts a command object, request object and returns a promise that is fulfilled with an Aws\ResultInterface object or rejected with an Aws\Exception\AwsException. A handler does not accept a next handler as it is terminal and expected to fulfill a command. If no handler is provided, a default Guzzle handler will be utilized.',

            'fn'       => [__CLASS__, '_apply_handler'],

            'default'  => [__CLASS__, '_default_handler']

        ],

        'app_id' => [

            'type' => 'value',

            'valid' => ['string'],

            'doc' => 'app_id(AppId) is an optional application specific identifier that can be set.

             When set it will be appended to the User-Agent header of every request in the form of App/{AppId}.

             This value is also sourced from environment variable AWS_SDK_UA_APP_ID or the shared config profile attribute sdk_ua_app_id.',

            'fn' => [__CLASS__, '_apply_app_id'],

            'default' => [__CLASS__, '_default_app_id']

        ],

        'ua_append' => [

            'type'     => 'value',

            'valid'    => ['string', 'array'],

            'doc'      => 'Provide a string or array of strings to send in the User-Agent header.',

            'fn'       => [__CLASS__, '_apply_user_agent'],

            'default'  => [],

        ],

        'idempotency_auto_fill' => [

            'type'      => 'value',

            'valid'     => ['bool', 'callable'],

            'doc'       => 'Set to false to disable SDK to populate parameters that enabled \'idempotencyToken\' trait with a random UUID v4 value on your behalf. Using default value \'true\' still allows parameter value to be overwritten when provided. Note: auto-fill only works when cryptographically secure random bytes generator functions(random_bytes, openssl_random_pseudo_bytes or mcrypt_create_iv) can be found. You may also provide a callable source of random bytes.',

            'default'   => true,

            'fn'        => [__CLASS__, '_apply_idempotency_auto_fill']

        ],

        'use_aws_shared_config_files' => [

            'type'      => 'value',

            'valid'     => ['bool'],

            'doc'       => 'Set to false to disable checking for shared aws config files usually located in \'~/.aws/config\' and \'~/.aws/credentials\'.  This will be ignored if you set the \'profile\' setting.',

            'default'   => true,

        ],

        'suppress_php_deprecation_warning' => [

            'type'      => 'value',

            'valid'     => ['bool'],

            'doc' => 'Set to true to suppress PHP runtime deprecation warnings. The current deprecation campaign is PHP versions 8.0.x and below, taking effect on 1/13/2025.',

            'default' => false,

            'fn' => [__CLASS__, '_apply_suppress_php_deprecation_warning']

        ],

        'account_id_endpoint_mode' => [

            'type'      => 'value',

            'valid'     => ['string'],

            'doc'       => 'Decides whether account_id must a be a required resolved credentials property. If this configuration is set to disabled, then account_id is not required. If set to preferred a warning will be logged when account_id is not resolved, and when set to required an exception will be thrown if account_id is not resolved.',

            'default'  => [__CLASS__, '_default_account_id_endpoint_mode'],

            'fn'       => [__CLASS__, '_apply_account_id_endpoint_mode']

        ],

        'sigv4a_signing_region_set' => [

            'type' => 'value',

            'valid' => ['string', 'array'],

            'doc' => 'A comma-delimited list of supported regions sent in sigv4a requests.',

            'fn' => [__CLASS__, '_apply_sigv4a_signing_region_set'],

            'default' => self::DEFAULT_FROM_ENV_INI

        ]

    ];

    /**

     * Gets an array of default client arguments, each argument containing a

     * hash of the following:

     *

     * - type: (string, required) option type described as follows:

     *   - value: The default option type.

     *   - config: The provided value is made available in the client's

     *     getConfig() method.

     * - valid: (array, required) Valid PHP types or class names. Note: null

     *   is not an allowed type.

     * - required: (bool, callable) Whether or not the argument is required.

     *   Provide a function that accepts an array of arguments and returns a

     *   string to provide a custom error message.

     * - default: (mixed) The default value of the argument if not provided. If

     *   a function is provided, then it will be invoked to provide a default

     *   value. The function is provided the array of options and is expected

     *   to return the default value of the option. The default value can be a

     *   closure and can not be a callable string that is not  part of the

     *   defaultArgs array.

     * - doc: (string) The argument documentation string.

     * - fn: (callable) Function used to apply the argument. The function

     *   accepts the provided value, array of arguments by reference, and an

     *   event emitter.

     *

     * Note: Order is honored and important when applying arguments.

     *

     * @return array

     */

    public static function getDefaultArguments()

    {

        return self::$defaultArgs;

    }

    /**

     * @param array $argDefinitions Client arguments.

     */

    public function __construct(array $argDefinitions)

    {

        $this->argDefinitions = $argDefinitions;

    }

    /**

     * Resolves client configuration options and attached event listeners.

     * Check for missing keys in passed arguments

     *

     * @param array       $args Provided constructor arguments.

     * @param HandlerList $list Handler list to augment.

     *

     * @return array Returns the array of provided options.

     * @throws \InvalidArgumentException

     * @see Aws\AwsClient::__construct for a list of available options.

     */

    public function resolve(array $args, HandlerList $list)

    {

        $args['config'] = [];

        foreach ($this->argDefinitions as $key => $a) {

            // Add defaults, validate required values, and skip if not set.

            if (!isset($args[$key])) {

                if (isset($a['default'])) {

                    // Merge defaults in when not present.

                    if (is_callable($a['default'])

                        && (

                            is_array($a['default'])

                            || $a['default'] instanceof \Closure

                        )

                    ) {

                        if ($a['default'] === self::DEFAULT_FROM_ENV_INI) {

                            $args[$key] = $a['default'](

                                $key,

                                $a['valid'][0] ?? 'string',

                                $args

                            );

                        } else {

                            $args[$key] = $a['default']($args);

                        }

                    } else {

                        $args[$key] = $a['default'];

                    }

                } elseif (empty($a['required'])) {

                    continue;

                } else {

                    $this->throwRequired($args);

                }

            }

            // Validate the types against the provided value.

            foreach ($a['valid'] as $check) {

                if (isset(self::$typeMap[$check])) {

                    $fn = self::$typeMap[$check];

                    if ($fn($args[$key])) {

                        goto is_valid;

                    }

                } elseif ($args[$key] instanceof $check) {

                    goto is_valid;

                }

            }

            $this->invalidType($key, $args[$key]);

            // Apply the value

            is_valid:

            if (isset($a['fn'])) {

                $a['fn']($args[$key], $args, $list);

            }

            if ($a['type'] === 'config') {

                $args['config'][$key] = $args[$key];

            }

        }

        $this->_apply_client_context_params($args);

        return $args;

    }

    /**

     * Creates a verbose error message for an invalid argument.

     *

     * @param string $name        Name of the argument that is missing.

     * @param array  $args        Provided arguments

     * @param bool   $useRequired Set to true to show the required fn text if

     *                            available instead of the documentation.

     * @return string

     */

    private function getArgMessage($name, $args = [], $useRequired = false)

    {

        $arg = $this->argDefinitions[$name];

        $msg = '';

        $modifiers = [];

        if (isset($arg['valid'])) {

            $modifiers[] = implode('|', $arg['valid']);

        }

        if (isset($arg['choice'])) {

            $modifiers[] = 'One of ' . implode(', ', $arg['choice']);

        }

        if ($modifiers) {

            $msg .= '(' . implode('; ', $modifiers) . ')';

        }

        $msg = wordwrap("{$name}: {$msg}", 75, "\n  ");

        if ($useRequired && is_callable($arg['required'])) {

            $msg .= "\n\n  ";

            $msg .= str_replace("\n", "\n  ", call_user_func($arg['required'], $args));

        } elseif (isset($arg['doc'])) {

            $msg .= wordwrap("\n\n  {$arg['doc']}", 75, "\n  ");

        }

        return $msg;

    }

    /**

     * Throw when an invalid type is encountered.

     *

     * @param string $name     Name of the value being validated.

     * @param mixed  $provided The provided value.

     * @throws \InvalidArgumentException

     */

    private function invalidType($name, $provided)

    {

        $expected = implode('|', $this->argDefinitions[$name]['valid']);

        $msg = "Invalid configuration value "

            . "provided for \"{$name}\". Expected {$expected}, but got "

            . describe_type($provided) . "\n\n"

            . $this->getArgMessage($name);

        throw new IAE($msg);

    }

    /**

     * Throws an exception for missing required arguments.

     *

     * @param array $args Passed in arguments.

     * @throws \InvalidArgumentException

     */

    private function throwRequired(array $args)

    {

        $missing = [];

        foreach ($this->argDefinitions as $k => $a) {

            if (empty($a['required'])

                || isset($a['default'])

                || isset($args[$k])

            ) {

                continue;

            }

            $missing[] = $this->getArgMessage($k, $args, true);

        }

        $msg = "Missing required client configuration options: \n\n";

        $msg .= implode("\n\n", $missing);

        throw new IAE($msg);

    }

    public static function _apply_retries($value, array &$args, HandlerList $list)

    {

        // A value of 0 for the config option disables retries

        if ($value) {

            $config = RetryConfigProvider::unwrap($value);

            if ($config->getMode() === 'legacy') {

                // # of retries is 1 less than # of attempts

                $decider = RetryMiddleware::createDefaultDecider(

                    $config->getMaxAttempts() - 1

                );

                $list->appendSign(

                    Middleware::retry($decider, null, $args['stats']['retries']),

                    'retry'

                );

            } else {

                $list->appendSign(

                    RetryMiddlewareV2::wrap(

                        $config,

                        ['collect_stats' => $args['stats']['retries']]

                    ),

                    'retry'

                );

            }

        }

    }

    public static function _apply_defaults($value, array &$args, HandlerList $list)

    {

        $config = ConfigModeProvider::unwrap($value);

        if ($config->getMode() !== 'legacy') {

            if (!isset($args['retries']) && !is_null($config->getRetryMode())) {

                $args['retries'] = ['mode' => $config->getRetryMode()];

            }

            if (

                !isset($args['sts_regional_endpoints'])

                && !is_null($config->getStsRegionalEndpoints())

            ) {

                $args['sts_regional_endpoints'] = ['mode' => $config->getStsRegionalEndpoints()];

            }

            if (

                !isset($args['s3_us_east_1_regional_endpoint'])

                && !is_null($config->getS3UsEast1RegionalEndpoints())

            ) {

                $args['s3_us_east_1_regional_endpoint'] = ['mode' => $config->getS3UsEast1RegionalEndpoints()];

            }

            if (!isset($args['http'])) {

                $args['http'] = [];

            }

            if (

                !isset($args['http']['connect_timeout'])

                && !is_null($config->getConnectTimeoutInMillis())

            ) {

                $args['http']['connect_timeout'] = $config->getConnectTimeoutInMillis() / 1000;

            }

            if (

                !isset($args['http']['timeout'])

                && !is_null($config->getHttpRequestTimeoutInMillis())

            ) {

                $args['http']['timeout'] = $config->getHttpRequestTimeoutInMillis() / 1000;

            }

        }

    }

    public static function _apply_disable_request_compression($value, array &$args) {

        if (is_callable($value)) {

            $value = $value();

        }

        if (!is_bool($value)) {

            throw new IAE(

                "Invalid configuration value provided for 'disable_request_compression'."

                . " value must be a bool."

            );

        }

        $args['config']['disable_request_compression'] = $value;

    }

    public static function _apply_min_compression_size($value, array &$args) {

        if (is_callable($value)) {

            $value = $value();

        }

        if (!is_int($value)

            || (is_int($value)

                && ($value < 0 || $value > 10485760))

        ) {

            throw new IAE(" Invalid configuration value provided for 'min_compression_size_bytes'."

                . " value must be an integer between 0 and 10485760, inclusive.");

        }

        $args['config']['request_min_compression_size_bytes'] = $value;

    }

    public static function _default_min_compression_size(array &$args) {

        return ConfigurationResolver::resolve(

            'request_min_compression_size_bytes',

            10240,

            'int',

            $args

        );

    }

    public static function _apply_credentials($value, array &$args)

    {

        if (is_callable($value)) {

            return;

        }

        if ($value instanceof CredentialsInterface) {

            $args['credentials'] = CredentialProvider::fromCredentials($value);

        } elseif (is_array($value)

            && isset($value['key'])

            && isset($value['secret'])

        ) {

            $args['credentials'] = CredentialProvider::fromCredentials(

                new Credentials(

                    $value['key'],

                    $value['secret'],

                    $value['token'] ?? null,

                    $value['expires'] ?? null,

                    $value['accountId'] ?? null

                )

            );

        } elseif ($value === false) {

            $args['credentials'] = CredentialProvider::fromCredentials(

                new Credentials('', '')

            );

            $args['config']['signature_version'] = 'anonymous';

            $args['config']['configured_signature_version'] = true;

        } elseif ($value instanceof CacheInterface) {

            $args['credentials'] = CredentialProvider::defaultProvider($args);

        } else {

            throw new IAE('Credentials must be an instance of '

                . "'" . CredentialsInterface::class . ', an associative '

                . 'array that contains "key", "secret", and an optional "token" '

                . 'key-value pairs, a credentials provider function, or false.');

        }

    }

    public static function _default_credential_provider(array $args)

    {

        return CredentialProvider::defaultProvider($args);

    }

    public static function _apply_token($value, array &$args)

    {

        if (is_callable($value)) {

            return;

        }

        if ($value instanceof Token) {

            $args['token'] = TokenProvider::fromToken($value);

        } elseif (is_array($value)

            && isset($value['token'])

        ) {

            $args['token'] = TokenProvider::fromToken(

                new Token(

                    $value['token'],

                    $value['expires'] ?? null

                )

            );

        } elseif ($value instanceof CacheInterface) {

            $args['token'] = TokenProvider::defaultProvider($args);

        } else {

            throw new IAE('Token must be an instance of '

                . TokenInterface::class . ', an associative '

                . 'array that contains "token" and an optional "expires" '

                . 'key-value pairs, a token provider function, or false.');

        }

    }

    public static function _default_token_provider(array $args)

    {

        return TokenProvider::defaultProvider($args);

    }

    public static function _apply_csm($value, array &$args, HandlerList $list)

    {

        if ($value === false) {

            $value = new Configuration(

                false,

                \Aws\ClientSideMonitoring\ConfigurationProvider::DEFAULT_HOST,

                \Aws\ClientSideMonitoring\ConfigurationProvider::DEFAULT_PORT,

                \Aws\ClientSideMonitoring\ConfigurationProvider::DEFAULT_CLIENT_ID

            );

            $args['csm'] = $value;

        }

        $list->appendBuild(

            ApiCallMonitoringMiddleware::wrap(

                $args['credentials'],

                $value,

                $args['region'],

                $args['api']->getServiceId()

            ),

            'ApiCallMonitoringMiddleware'

        );

        $list->appendAttempt(

            ApiCallAttemptMonitoringMiddleware::wrap(

                $args['credentials'],

                $value,

                $args['region'],

                $args['api']->getServiceId()

            ),

            'ApiCallAttemptMonitoringMiddleware'

        );

    }

    public static function _apply_api_provider(callable $value, array &$args)

    {

        $api = new Service(

            ApiProvider::resolve(

                $value,

                'api',

                $args['service'],

                $args['version']

            ),

            $value

        );

        if (

            empty($args['config']['signing_name'])

            && isset($api['metadata']['signingName'])

        ) {

            $args['config']['signing_name'] = $api['metadata']['signingName'];

        }

        $args['api'] = $api;

        $args['parser'] = Service::createParser($api);

        $args['error_parser'] = Service::createErrorParser($api->getProtocol(), $api);

    }

    public static function _apply_endpoint_provider($value, array &$args)

    {

        if (!isset($args['endpoint'])) {

            if ($value instanceof \Aws\EndpointV2\EndpointProviderV2) {

                $options = self::getEndpointProviderOptions($args);

                $value = PartitionEndpointProvider::defaultProvider($options)

                    ->getPartition($args['region'], $args['service']);

            }

            $endpointPrefix = $args['api']['metadata']['endpointPrefix'] ?? $args['service'];

            // Check region is a valid host label when it is being used to

            // generate an endpoint

            if (!self::isValidRegion($args['region'])) {

                throw new InvalidRegionException('Region must be a valid RFC'

                    . ' host label.');

            }

            $serviceEndpoints =

                is_array($value) && isset($value['services'][$args['service']]['endpoints'])

                    ? $value['services'][$args['service']]['endpoints']

                    : null;

            if (isset($serviceEndpoints[$args['region']]['deprecated'])) {

                trigger_error("The service " . $args['service'] . "has "

                    . " deprecated the region " . $args['region'] . ".",

                    E_USER_WARNING

                );

            }

            $args['region'] = \Aws\strip_fips_pseudo_regions($args['region']);

            // Invoke the endpoint provider and throw if it does not resolve.

            $result = EndpointProvider::resolve($value, [

                'service' => $endpointPrefix,

                'region'  => $args['region'],

                'scheme'  => $args['scheme'],

                'options' => self::getEndpointProviderOptions($args),

            ]);

            $args['endpoint'] = $result['endpoint'];

            if (empty($args['config']['signature_version'])) {

                if (

                    isset($args['api'])

                    && $args['api']->getSignatureVersion() == 'bearer'

                ) {

                    $args['config']['signature_version'] = 'bearer';

                } elseif (isset($result['signatureVersion'])) {

                    $args['config']['signature_version'] = $result['signatureVersion'];

                }

            }

            if (

                empty($args['config']['signing_region'])

                && isset($result['signingRegion'])

            ) {

                $args['config']['signing_region'] = $result['signingRegion'];

            }

            if (

                empty($args['config']['signing_name'])

                && isset($result['signingName'])

            ) {

                $args['config']['signing_name'] = $result['signingName'];

            }

        }

    }

    public static function _apply_endpoint_discovery($value, array &$args) {

        $args['endpoint_discovery'] = $value;

    }

    public static function _default_endpoint_discovery_provider(array $args)

    {

        return ConfigurationProvider::defaultProvider($args);

    }

    public static function _apply_use_fips_endpoint($value, array &$args) {

        if ($value instanceof CacheInterface) {

            $value = UseFipsConfigProvider::defaultProvider($args);

        }

        if (is_callable($value)) {

            $value = $value();

        }

        if ($value instanceof PromiseInterface) {

            $value = $value->wait();

        }

        if ($value instanceof UseFipsEndpointConfigurationInterface) {

            $args['config']['use_fips_endpoint'] = $value;

        } else {

            // The Configuration class itself will validate other inputs

            $args['config']['use_fips_endpoint'] = new UseFipsEndpointConfiguration($value);

        }

    }

    public static function _default_use_fips_endpoint(array &$args) {

        return UseFipsConfigProvider::defaultProvider($args);

    }

    public static function _apply_use_dual_stack_endpoint($value, array &$args) {

        if ($value instanceof CacheInterface) {

            $value = UseDualStackConfigProvider::defaultProvider($args);

        }

        if (is_callable($value)) {

            $value = $value();

        }

        if ($value instanceof PromiseInterface) {

            $value = $value->wait();

        }

        if ($value instanceof UseDualStackEndpointConfigurationInterface) {

            $args['config']['use_dual_stack_endpoint'] = $value;

        } else {

            // The Configuration class itself will validate other inputs

            $args['config']['use_dual_stack_endpoint'] =

                new UseDualStackEndpointConfiguration($value, $args['region']);

        }

    }

    public static function _default_use_dual_stack_endpoint(array &$args) {

        return UseDualStackConfigProvider::defaultProvider($args);

    }

    public static function _apply_serializer($value, array &$args, HandlerList $list)

    {

        $list->prependBuild(Middleware::requestBuilder($value), 'builder');

    }

    public static function _apply_debug($value, array &$args, HandlerList $list)

    {

        if ($value !== false) {

            $list->interpose(

                new TraceMiddleware(

                    $value === true ? [] : $value,

                    $args['api'])

            );

        }

    }

    public static function _apply_stats($value, array &$args, HandlerList $list)

    {

        // Create an array of stat collectors that are disabled (set to false)

        // by default. If the user has passed in true, enable all stat

        // collectors.

        $defaults = array_fill_keys(

            ['http', 'retries', 'timer'],

            $value === true

        );

        $args['stats'] = is_array($value)

            ? array_replace($defaults, $value)

            : $defaults;

        if ($args['stats']['timer']) {

            $list->prependInit(Middleware::timer(), 'timer');

        }

    }

    public static function _apply_profile($_, array &$args)

    {

        $args['credentials'] = CredentialProvider::ini($args['profile']);

    }

    public static function _apply_validate($value, array &$args, HandlerList $list)

    {

        if ($value === false) {

            return;

        }

        $validator = $value === true

            ? new Validator()

            : new Validator($value);

        $list->appendValidate(

            Middleware::validation($args['api'], $validator),

            'validation'

        );

    }

    public static function _apply_handler($value, array &$args, HandlerList $list)

    {

        $list->setHandler($value);

    }

    public static function _default_handler(array &$args)

    {

        return new WrappedHttpHandler(

            default_http_handler(),

            $args['parser'],

            $args['error_parser'],

            $args['exception_class'],

            $args['stats']['http']

        );

    }

    public static function _apply_http_handler($value, array &$args, HandlerList $list)

    {

        $args['handler'] = new WrappedHttpHandler(

            $value,

            $args['parser'],

            $args['error_parser'],

            $args['exception_class'],

            $args['stats']['http']

        );

    }

    public static function _apply_app_id($value, array &$args)

    {

        // AppId should not be longer than 50 chars

        static $MAX_APP_ID_LENGTH = 50;

        if (strlen($value) > $MAX_APP_ID_LENGTH) {

            trigger_error("The provided or configured value for `AppId`, "

                ."which is an user agent parameter, exceeds the maximum length of "

            ."$MAX_APP_ID_LENGTH characters.", E_USER_WARNING);

        }

        $args['app_id'] = $value;

    }

    public static function _default_app_id(array $args)

    {

        return ConfigurationResolver::resolve(

            'sdk_ua_app_id',

            '',

            'string',