get_resource_type - PHP code example

PHP Function Get_Resource_Type

Article about php function get_resource_type

The get_resource_type() function is an inbuilt PHP function used to return the type of resource. The function takes a single parameter, which is the evaluated resource handle. The function returns a string if the passed resource is of type resource else it will return “Unknown”. This function is used by many internal functions like fopen.

Resource is a special data type in PHP which acts as a reference to external source of data such as stream, file or database. PHP’s Zend engine uses reference counting system so that once the resource variable loses its reference, memory associated with it will be automatically destroyed by garbage collector. Various PHP functions create resources which can be opened or closed by the user.

The get_resource_type() function provides a simple, sane and safe way to retrieve the resource ID of a variable. It essentially does an int cast of the resource variable to make it easier for the programmer to identify the handle type. This function is available since PHP 8. It can also be polyfilled in older versions of PHP. It’s a very useful function which can be used to ensure that the correct type of resource is being used in a context and also to avoid errors caused by working with mixed data types. This function is very useful for developers and can be a time saver for them.

get_resource_type example

function is_gd_image( $image ) {
    if ( $image instanceof GdImage
        || is_resource( $image ) && 'gd' === get_resource_type( $image )
    ) {
        return true;
    }

    return false;
}

/** * Creates a new GD image resource with transparency support. * * @todo Deprecate if possible. * * @since 2.9.0 * * @param int $width Image width in pixels. * @param int $height Image height in pixels. * @return resource|GdImage|false The GD image resource or GdImage instance on success. * False on failure. */

    public static function dump(mixed $value, int $flags = 0): string
    {
        switch (true) {
            case \is_resource($value):
                if (Yaml::DUMP_EXCEPTION_ON_INVALID_TYPE & $flags) {
                    throw new DumpException(sprintf('Unable to dump PHP resources in a YAML file ("%s").', get_resource_type($value)));
                }

                return self::dumpNull($flags);
            case $value instanceof \DateTimeInterface:
                return $value->format(match (true) {
                    !$length = \strlen(rtrim($value->format('u'), '0')) => 'c',
                    $length < 4 => 'Y-m-d\TH:i:s.vP',
                    default => 'Y-m-d\TH:i:s.uP',
                });
            case $value instanceof \UnitEnum:
                return sprintf('!php/const %s::%s', $value::class, $value->name);

$result[$key] = ['array', $this->flattenArgs($value, $level + 1, $count)];
                }
            } elseif (null === $value) {
                $result[$key] = ['null', null];
            } elseif (\is_bool($value)) {
                $result[$key] = ['boolean', $value];
            } elseif (\is_int($value)) {
                $result[$key] = ['integer', $value];
            } elseif (\is_float($value)) {
                $result[$key] = ['float', $value];
            } elseif (\is_resource($value)) {
                $result[$key] = ['resource', get_resource_type($value)];
            } else {
                $result[$key] = ['string', (string) $value];
            }
        }

        return $result;
    }

    private function getClassNameFromIncomplete(\__PHP_Incomplete_Class $value): string
    {
        $array = new \ArrayObject($value);

    public function setStreamContext($context)
    {
        if (is_resource($context) && get_resource_type($context) == 'stream-context') {
            $this->_context = $context;

        } elseif (is_array($context)) {
            $this->_context = stream_context_create($context);

        } else {
            // Invalid parameter             throw new Zend_Http_Client_Adapter_Exception(
                "Expecting either a stream context resource or array, got " . gettype($context)
            );
        }

// remote files not supported             if (preg_match('#^(ht|f)tps?://#', $filename)) {
                throw new getid3_exception('Remote files are not supported - please copy the file locally first');
            }

            $filename = str_replace('/', DIRECTORY_SEPARATOR, $filename);
            //$filename = preg_replace('#(?<!gs:)('.preg_quote(DIRECTORY_SEPARATOR).'{2,})#', DIRECTORY_SEPARATOR, $filename);
            // open local file             //if (is_readable($filename) && is_file($filename) && ($this->fp = fopen($filename, 'rb'))) { // see https://www.getid3.org/phpBB3/viewtopic.php?t=1720             if (($fp != null) && ((get_resource_type($fp) == 'file') || (get_resource_type($fp) == 'stream'))) {
                $this->fp = $fp;
            } elseif ((is_readable($filename) || file_exists($filename)) && is_file($filename) && ($this->fp = fopen($filename, 'rb'))) {
                // great             } else {
                $errormessagelist = array();
                if (!is_readable($filename)) {
                    $errormessagelist[] = '!is_readable';
                }
                if (!is_file($filename)) {
                    $errormessagelist[] = '!is_file';
                }

foreach ($var as $k => $v) {
                [$value, $e, $r] = $this->sanitizeParam($v, null);
                $explainable = $explainable && $e;
                $runnable = $runnable && $r;
                $a[$k] = $value;
            }

            return [$a, $explainable, $runnable];
        }

        if (\is_resource($var)) {
            return [sprintf('/* Resource(%s) */', get_resource_type($var)), false, false];
        }

        return [$var, true, true];
    }

    private function executionTimePercentage(float $executionTimeMS, float $totalExecutionTimeMS): float
    {
        if (!$totalExecutionTimeMS) {
            return 0;
        }

$this->dumpLine($cursor->depth, true);
    }

    /** * Returns true if the stream supports colorization. * * Reference: Composer\XdebugHandler\Process::supportsColor * https://github.com/composer/xdebug-handler */
    private function hasColorSupport(mixed $stream): bool
    {
        if (!\is_resource($stream) || 'stream' !== get_resource_type($stream)) {
            return false;
        }

        // Follow https://no-color.org/         if (isset($_SERVER['NO_COLOR']) || false !== getenv('NO_COLOR')) {
            return false;
        }

        if ('Hyper' === getenv('TERM_PROGRAM')) {
            return true;
        }

switch (true) {
                    case is_object($value):
                        return sprintf('Object(%s)', get_class($value));

                    case is_array($value):
                        return $value !== [] ? '[...]' : '[]';

                    case $value === null:
                        return 'null';

                    case is_resource($value):
                        return sprintf('resource (%s)', get_resource_type($value));

                    default:
                        return var_export($value, true);
                }
            }, $frame['args']));

            $backtraces[] = sprintf(
                '%s %s: %s%s%s(%s)',
                $idx,
                clean_path($frame['file']),
                $frame['class'],

else {
                            $stub = $objRefs[$h];
                            ++$stub->refCount;
                            $a = null;
                        }
                        break;

                    default: // resource                         if (empty($resRefs[$h = (int) $v])) {
                            $stub = new Stub();
                            $stub->type = Stub::TYPE_RESOURCE;
                            if ('Unknown' === $stub->class = @get_resource_type($v)) {
                                $stub->class = 'Closed';
                            }
                            $stub->value = $v;
                            $stub->handle = $h;
                            $a = $this->castResource($stub, 0 < $i);
                            $stub->value = null;
                            if (0 <= $maxItems && $maxItems <= $pos && $minimumDepthReached) {
                                $stub->cut = \count($a);
                                $a = null;
                            }
                        }

return $normalized;
        }

        if (\is_object($data)) {
            if (!$this->normalizers) {
                throw new LogicException('You must register at least one normalizer to be able to normalize objects.');
            }

            throw new NotNormalizableValueException(sprintf('Could not normalize object of type "%s", no supporting normalizer found.', get_debug_type($data)));
        }

        throw new NotNormalizableValueException('An unexpected value could not be normalized: '.(!\is_resource($data) ? var_export($data, true) : sprintf('"%s" resource', get_resource_type($data))));
    }

    /** * @throws NotNormalizableValueException */
    public function denormalize(mixed $data, string $type, string $format = null, array $context = []): mixed
    {
        if (isset($context[DenormalizerInterface::COLLECT_DENORMALIZATION_ERRORS], $context['not_normalizable_value_exceptions'])) {
            throw new LogicException('Passing a value for "not_normalizable_value_exceptions" context key is not allowed.');
        }

        switch (true) {
            case null === $value: return 'null';
            case \is_bool($value): return 'bool';
            case \is_string($value): return 'string';
            case \is_array($value): return 'array';
            case \is_int($value): return 'int';
            case \is_float($value): return 'float';
            case \is_object($value): break;
            case $value instanceof \__PHP_Incomplete_Class: return '__PHP_Incomplete_Class';
            default:
                if (null === $type = @get_resource_type($value)) {
                    return 'unknown';
                }

                if ('Unknown' === $type) {
                    $type = 'closed';
                }

                return "resource ($type)";
        }

        $class = \get_class($value);

    public static function prepare($values, $objectsPool, &$refsPool, &$objectsCount, &$valuesAreStatic)
    {
        $refs = $values;
        foreach ($values as $k => $value) {
            if (\is_resource($value)) {
                throw new NotInstantiableTypeException(get_resource_type($value).' resource');
            }
            $refs[$k] = $objectsPool;

            if ($isRef = !$valueIsStatic = $values[$k] !== $objectsPool) {
                $values[$k] = &$value; // Break hard references to make $values completely                 unset($value);         // independent from the original structure                 $refs[$k] = $value = $values[$k];
                if ($value instanceof Reference && 0 > $value->id) {
                    $valuesAreStatic = false;
                    ++$value->count;
                    continue;
                }

/** * @param resource $stream A stream resource * @param int $verbosity The verbosity level (one of the VERBOSITY constants in OutputInterface) * @param bool|null $decorated Whether to decorate messages (null for auto-guessing) * @param OutputFormatterInterface|null $formatter Output formatter instance (null to use default OutputFormatter) * * @throws InvalidArgumentException When first argument is not a real stream */
    public function __construct($stream, int $verbosity = self::VERBOSITY_NORMAL, bool $decorated = null, OutputFormatterInterface $formatter = null)
    {
        if (!\is_resource($stream) || 'stream' !== get_resource_type($stream)) {
            throw new InvalidArgumentException('The StreamOutput class needs a stream as its first argument.');
        }

        $this->stream = $stream;

        $decorated ??= $this->hasColorSupport();

        parent::__construct($verbosity, $decorated, $formatter);
    }

    /** * Gets the stream attached to this StreamOutput instance. * * @return resource */

// top level data object was normalized into a scalar             if (!$parentNode->parentNode->parentNode) {
                $root = $parentNode->parentNode;
                $root->removeChild($parentNode);

                return $this->appendNode($root, $data, $format, $context, $xmlRootNodeName);
            }

            return $this->appendNode($parentNode, $data, $format, $context, 'data');
        }

        throw new NotEncodableValueException('An unexpected value could not be serialized: '.(!\is_resource($data) ? var_export($data, true) : sprintf('%s resource', get_resource_type($data))));
    }

    /** * Selects the type of node to create and appends it to the parent. */
    private function appendNode(\DOMNode $parentNode, mixed $data, string $format, array $context, string $nodeName, string $key = null): bool
    {
        $dom = $parentNode instanceof \DOMDocument ? $parentNode : $parentNode->ownerDocument;
        $node = $dom->createElement($nodeName);
        if (null !== $key) {
            $node->setAttribute('key', $key);
        }

case 'array':
                $this->type = self::TYPE_ARRAY;
                $this->class = self::ARRAY_ASSOC;
                $this->cut = $this->value = \count($value);
                break;

            case 'resource':
            case 'unknown type':
            case 'resource (closed)':
                $this->type = self::TYPE_RESOURCE;
                $this->handle = (int) $value;
                if ('Unknown' === $this->class = @get_resource_type($value)) {
                    $this->class = 'Closed';
                }
                $this->cut = -1;
                break;

            case 'string':
                $this->type = self::TYPE_STRING;
                $this->class = preg_match('//u', $value) ? self::STRING_UTF8 : self::STRING_BINARY;
                $this->cut = self::STRING_BINARY === $this->class ? \strlen($value) : mb_strlen($value, 'UTF-8');
                $this->value = '';
                break;
        }