PHP Type Formatter

Minimalistic, lightweight library for converting PHP data types to readable strings. Great for type-safe outputs, exception messages, transparency during debugging, and similar things. Also helps avoiding innate problems such as printing recursive objects and large arrays.

Requirements

"php": ">=7.2",
"ext-mbstring": ">=7.2",
"doctrine/collections": "^1"

For more information, see the composer.json file.

License & Disclaimer

See LICENSE file. Basically: Use this library at your own risk.

Installation

Via Composer (https://packagist.org/packages/kafoso/type-formatter):

composer install kafoso/type-formatter

Via GitHub:

git clone [email protected]:kafoso/type-formatter.git

Fundamentals

Type conversions to string

The data types are converted as illustrated in the table below.

Type	Conversion logic	Example(s)	Note
Null	As is.	null
Booleans	As is.	true false
Float numbers	As is.	3.14	Standard float-to-string conversion rounding will occur, as produced by strval(3.14).
Integers	As is.	42
Strings	As is or as a sample (substring).	"foo" "bar ..." (sample)	If you wish to control how strings are presented or apply conditions, you may do so by providing an instance of \Kafoso\TypeFormatter\Type\StringFormatterInterface. More on this interface and implementation further down.
Arrays	As is or as a sample.	[0 => "foo"] [0 => "bar" ... and 9 more elements]	Sub-arrays By default, no sub-arrays are displayed; i.e. the depth is zero. However, a custom depth may be specified. Sub-arrays with depth 0 (zero) may appear as such: [0 => (array(1)) [...]] Sub-arrays with depth 1 may appear as such: [0 => (array(1)) ["foo"]] Sampling and sample size By default, a maximum of 3 elements are displayed, before the " ... and X more elements" message is displayed. This number is also customizible. Custom array-to-string conversion If you wish to customize how arrays are being converted to a string, you may do so by providing an instance of \Kafoso\TypeFormatter\Type\ArrayFormatterInterface. More on this interface and implementation further down.
Objects	Class namespace with leading backslash.	\stdClass \class@anonymous/foo/bar/baz.php0x11038bd57	Objects are rather complex types. As such, something sensible besides its class name cannot be reliably displayed. Not even using __toString or similar methods. Custom object-to-string conversion If you wish to customize how objects are being converted to a string, you may do so by providing an instance of \Kafoso\TypeFormatter\Type\ObjectFormatterInterface. More on this interface and implementation further down. This is especially useful for displaying relevant information in classes such as IDs in Doctrine ORM entities.
Resource	A text and the resource's ID.	#Resource id #2	Resources can be many different things. A file pointer, database connection, image canvas, etc. As such, only the bare minimum of information is displayed. Custom resource-to-string conversion If you wish to customize how resources are being converted to a string, you may do so by providing an instance of \Kafoso\TypeFormatter\Type\ResourceFormatterInterface. More on this interface and implementation further down.

Output examples

Echo

<?php
use Kafoso\TypeFormatter\TypeFormatter;

$typeFormatter = TypeFormatter::create();

echo sprintf(
    "%s %s %s %s",
    $typeFormatter->cast(null),
    $typeFormatter->cast(true),
    $typeFormatter->cast("foo"),
    $typeFormatter->cast(new \stdClass)
);

/**
 * Will output:
 * null true "foo" \stdClass
 */

Exception

<?php
use Kafoso\TypeFormatter\TypeFormatter;

/**
 * @param string|int $value
 * @throws \InvalidArgumentException
 */
function foo($value){
    if (false == is_string($value) && false == is_int($value)) {
        throw new \InvalidArgumentException(sprintf(
            "Expects argument \$value to be a string or an integer. Found: %s",
            TypeFormatter::create()->typeCast($value)
        ));
    }
};

foo(["bar"]);

/**
 * Exception message will read:
 * Expects argument $value to be a string or an integer. Found: (array(1)) [(int) 0 => (string(3)) "bar"]
 */

Usage

\Kafoso\TypeFormatter\TypeFormatter is immutable. As such, it may only be configured upon construction.

The standard formatter

By default, Kafoso\TypeFormatter\TypeFormatter::create() returns a new instance every time. If you wish to re-use the same instance over and over, you have two options.

Option 1: Store it in a variable and use that. As such:

<?php
use Kafoso\TypeFormatter\TypeFormatter;

$typeFormatter = TypeFormatter::create();

Option 2: Use a dependency container; see below.

Dependency container (default & variations)

For ease-of-use, you may store formatters statically in Kafoso\TypeFormatter\TypeFormatter.

You may specify 2 types of dependencies.

Default:

<?php
use Kafoso\TypeFormatter\TypeFormatter;

$typeFormatter = TypeFormatter::getDefault();
$typeFormatter = $typeFormatter->withArrayDepthMaximum(2);
TypeFormatter::setDefault($typeFormatter);

Variations:

<?php
use Kafoso\TypeFormatter\TypeFormatter;

$typeFormatter = TypeFormatter::create();
$typeFormatter = $typeFormatter->withArrayDepthMaximum(3);
TypeFormatter::setVariation("variation1", $typeFormatter);
$typeFormatter = TypeFormatter::getVariation("variation1");

Use a real Dependency Injection Container

Alternatively, use an actual Dependency Injection Container (DIC) such as Pimple. However, this means you will have to pass around the dependencies everywhere you need them, which - from a SOLID perspective - is nice, but not always very practical.

A custom basic formatter

You may customize the formatter to your specific needs, e.g. changing string sample size, array depth, or providing custom array and/or object formatters. Afterwards, you may store it as the default or a variation for later re-use.

<?php
use Kafoso\TypeFormatter\Encoding;
use Kafoso\TypeFormatter\TypeFormatter;

$customTypeFormatter = TypeFormatter::create();
$customTypeFormatter = $customTypeFormatter->withArrayDepthMaximum(2);
$customTypeFormatter = $customTypeFormatter->withArraySampleSize(3);
$customTypeFormatter = $customTypeFormatter->withStringSampleSize(4);
$customTypeFormatter = $customTypeFormatter->withStringQuotingCharacter("`");

Type specific formatters

The following type specific formatters exists, which may help providing additional information. Especially useful for printing relevant information relating to an object.

These formatters are injected into the desired instance of \Kafoso\TypeFormatter\TypeFormatter using the with* methods. Do however notice, that \Kafoso\TypeFormatter\TypeFormatter is immutable.

Data type	\Kafoso\TypeFormatter\TypeFormatter method	Interface	Note
array	withCustomArrayFormatterCollection	\Kafoso\TypeFormatter\Type\ArrayFormatterInterface	See usage example in Custom array formatter further down.
object	withCustomObjectFormatterCollection	\Kafoso\TypeFormatter\Type\ObjectFormatterInterface	See usage example in Custom object formatter further down. Notice: This library ships with a series of ready-to-use object formatters. These may be found under \Kafoso\TypeFormatter\Type\Objects. Details below.
resource	withCustomResourceFormatterCollection	\Kafoso\TypeFormatter\Type\ResourceFormatterInterface	See usage example in Custom resource formatter further down.
string	withCustomStringFormatterCollection	\Kafoso\TypeFormatter\Type\StringFormatterInterface	See usage example in Custom string formatter further down.

Multiple custom formatters can be provided, such that they each handle only specific cases. Order is significant.

Ultimately, all custom formatters fall back to their respective standard formatters.

Included object formatters

The following object formatters are readily available. You may use them as-is or extend them, providing your own custom logic. Everything is very Open-closed Principle.

Namespace: \Kafoso\TypeFormatter\Type\Objects

Class name	Description	Output example(s)
DateTimeInterfaceFormatter	Formats \DateTimeInterface objects, appending ISO 8601 time in parenthesis.	\DateTimeImmutable ("2019-01-01T00:00:00+00:00")
DirectoryFormatter	Formats \Directory objects, as produced by dir(__DIR__).	\Directory ($path = "/foo.php")
DoctrineEntityFormatter	Formats Doctrine ORM entities using the provided \Doctrine\ORM\EntityManager.	\User {$id = 1} \Message {$uuid = "ad39f689-1070-41cd-9e0f-17112abdfc85"}
PublicVariableFormatter	Formats any object which has publicly accessible variables.	\stdClass {$foo = "bar"}
TextuallyIdentifiableInterfaceFormatter	Formats objects, which implement the interface \Kafoso\TypeFormatter\Contract\TextuallyIdentifiableInterface.	\MyUserClass (USER.ID = 22)
ThrowableFormatter	Formats instances of \Throwable. Notice: The output is greatly simplified compared to properly dumping a \Throwable with stack trace and everything else.	\RuntimeException {$code = 0, $file = "/foo.php", $line = 22, $message = "bar", $previous = null}

Custom array formatter

<?php
use Kafoso\TypeFormatter\Abstraction\Type\AbstractFormatter;
use Kafoso\TypeFormatter\Collection\Type\ArrayFormatterCollection;
use Kafoso\TypeFormatter\Encoding;
use Kafoso\TypeFormatter\Type\ArrayFormatterInterface;
use Kafoso\TypeFormatter\TypeFormatter;

$customTypeFormatter = TypeFormatter::create();
$customTypeFormatter = $customTypeFormatter->withCustomArrayFormatterCollection(new ArrayFormatterCollection([
    new class extends AbstractFormatter implements ArrayFormatterInterface
    {
        /**
         * @inheritDoc
         */
        public function format(array $array): ?string
        {
            if (1 == count($array)) {
                return print_r($array, true);
            }
            if (2 == count($array)) {
                return "I am an array!";
            }
            if (3 === count($array)) {
                $array[0] = "SURPRISE!";
                // Override and use DefaultArrayFormatter for rendering output
                return $this->getTypeFormatter()->getDefaultArrayFormatter()->format($array);
            }
            return null; // Pass on to next formatter or lastly DefaultArrayFormatter
        }
    }
]));

echo $customTypeFormatter->cast(["foo"]) . PHP_EOL;

/**
 * Will output:
 * Array
 * (
 *     [0] => foo
 * )
 */

echo $customTypeFormatter->cast(["foo", "bar"]) . PHP_EOL;

/**
 * Will output:
 * I am an array!
 */

echo $customTypeFormatter->cast(["foo", "bar", "baz"]) . PHP_EOL;

/**
 * Will output:
 * [0 => "SURPRISE!", 1 => "bar", 2 => "baz"]
 */

echo $customTypeFormatter->cast(["foo", "bar", "baz", "bim"]) . PHP_EOL;

/**
 * Will output:
 * [0 => "foo", 1 => "bar", 2 => "baz", ... and 1 more element] (sample)
 */

echo $customTypeFormatter->typeCast(["foo", "bar", "baz", "bim"]) . PHP_EOL;

/**
 * Will output:
 * (array(4)) [(int) 0 => (string(3)) "foo", (int) 1 => (string(3)) "bar", (int) 2 => (string(3)) "baz", ... and 1 more element] (sample)
 */

Custom object formatter

In this example, \DateTimeInterface, \Throwable, and the Doctrine ORM EntityManager is utilized to supply good real-world use cases.

<?php
use Doctrine\Common\Persistence\Proxy;
use Doctrine\ORM\EntityManager;
use Doctrine\ORM\Mapping\ClassMetadataFactory;
use Kafoso\TypeFormatter\Abstraction\Type\AbstractFormatter;
use Kafoso\TypeFormatter\Collection\Type\ObjectFormatterCollection;
use Kafoso\TypeFormatter\Encoding;
use Kafoso\TypeFormatter\Type\DefaultObjectFormatter;
use Kafoso\TypeFormatter\Type\ObjectFormatterInterface;
use Kafoso\TypeFormatter\TypeFormatter;
use PHPUnit\Framework\MockObject\Generator;
use PHPUnit\Framework\TestCase;

$generator = new Generator;
$entityManager = $generator->getMock(EntityManager::class, [], [], '', false);
$metadataFactory = $generator->getMock(ClassMetadataFactory::class, [], [], '', false);
$metadataFactory
    ->expects(TestCase::any())
    ->method('isTransient')
    ->withConsecutive(TestCase::equalTo('User'), TestCase::equalTo('stdClass'))
    ->willReturnOnConsecutiveCalls(TestCase::returnValue(false), TestCase::returnValue(true));
$entityManager
    ->expects(TestCase::any())
    ->method('getMetadataFactory')
    ->will(TestCase::returnValue($metadataFactory));

$customTypeFormatter = TypeFormatter::create();
$customTypeFormatter = $customTypeFormatter->withCustomObjectFormatterCollection(new ObjectFormatterCollection([
    new class ($entityManager) extends AbstractFormatter implements ObjectFormatterInterface
    {
        /**
         * @inheritDoc
         */
        public function format($object): ?string
        {
            if (false == is_object($object)) {
                return null; // Pass on to next formatter or lastly DefaultObjectFormatter
            }
            if ($object instanceof \DateTimeInterface) {
                return sprintf(
                    "\\%s (%s)",
                    DefaultObjectFormatter::getClassName($object),
                    $object->format("c")
                );
            }
            return null; // Pass on to next formatter or lastly DefaultObjectFormatter
        }
    },
    new class extends AbstractFormatter implements ObjectFormatterInterface
    {
        /**
         * @inheritDoc
         */
        public function format($object): ?string
        {
            if (false == is_object($object)) {
                return null; // Pass on to next formatter or lastly DefaultObjectFormatter
            }
            if ($object instanceof \Throwable) {
                return sprintf(
                    "\\%s {\$code = %s, \$file = %s, \$line = %s, \$message = %s}",
                    DefaultObjectFormatter::getClassName($object),
                    $this->getTypeFormatter()->cast($object->getCode()),
                    $this->getTypeFormatter()->cast($object->getFile(), false),
                    $this->getTypeFormatter()->cast($object->getLine()),
                    $this->getTypeFormatter()->cast($object->getMessage())
                );
            }
            return null; // Pass on to next formatter or lastly DefaultObjectFormatter
        }
    },
    new class ($entityManager) extends AbstractFormatter implements ObjectFormatterInterface
    {
        /**
         * @var EntityManager
         */
        private $entityManager;

        public function __construct(EntityManager $entityManager)
        {
            $this->entityManager = $entityManager;
        }

        /**
         * @inheritDoc
         */
        public function format($object): ?string
        {
            if (false == is_object($object)) {
                return null; // Pass on to next formatter or lastly DefaultObjectFormatter
            }
            $className = ($object instanceof Proxy) ? get_parent_class($object) : DefaultObjectFormatter::getClassName($object);
            $isEntity = (false == $this->entityManager->getMetadataFactory()->isTransient($className));
            $id = null;
            if ($isEntity && method_exists($object, 'getId')) {
                // You may of course implement logic, which can extract and present any @ORM\Id columns, even composite IDs.
                $id = $object->getId();
            }
            if (is_int($id)) {
                return sprintf(
                    "\\%s {\$id = %d}",
                    $className,
                    $id
                );
            }
            return null; // Pass on to next formatter or lastly DefaultObjectFormatter
        }
    },
]));

echo $customTypeFormatter->cast(new \stdClass) . PHP_EOL;

/**
 * Will output (standard TypeFormatter object-to-string output):
 * \stdClass
 */

echo $customTypeFormatter->cast(new \DateTimeImmutable("2019-01-01T00:00:00+00:00")) . PHP_EOL;

/**
 * Will output:
 * \DateTimeImmutable ("2019-01-01T00:00:00+00:00")
 */

class User
{
    /**
     * @ORM\Id
     * @ORM\Column(type="integer")
     */
    private $id = null;

    public function getId(): ?int
    {
        return $this->id;
    }
}
$doctrineEntity = new \User;

// Pretend we fetch it from a database
$reflectionObject = new \ReflectionObject($doctrineEntity);
$reflectionProperty = $reflectionObject->getProperty("id");
$reflectionProperty->setAccessible(true);
$reflectionProperty->setValue($doctrineEntity, 1);

echo $customTypeFormatter->cast($doctrineEntity) . PHP_EOL;

/**
 * Will output:
 * \User {$id = 1}
 */

echo $customTypeFormatter->cast(new \RuntimeException("test", 1)) . PHP_EOL;

/**
 * Will output:
 * \RuntimeException {$code = 1, $file = "<file>", $line = <line>, $message = "test"}
 * , where:
 *    - <file> is the path this this file.
 *    - <line> is the line number at which the \RuntimeException is instantiated.
 */

Custom resource formatter

<?php
use Kafoso\TypeFormatter\Abstraction\Type\AbstractFormatter;
use Kafoso\TypeFormatter\Collection\Type\ResourceFormatterCollection;
use Kafoso\TypeFormatter\Encoding;
use Kafoso\TypeFormatter\Type\ResourceFormatterInterface;
use Kafoso\TypeFormatter\TypeFormatter;

$customTypeFormatter = TypeFormatter::create();
$customTypeFormatter = $customTypeFormatter->withCustomResourceFormatterCollection(new ResourceFormatterCollection([
    new class extends AbstractFormatter implements ResourceFormatterInterface
    {
        /**
         * @inheritDoc
         */
        public function format($resource): ?string
        {
            if (false == is_resource($resource)) {
                return null; // Pass on to next formatter or lastly DefaultResourceFormatter
            }
            if ("stream" === get_resource_type($resource)) {
                return "opendir/fopen/tmpfile/popen/fsockopen/pfsockopen {$resource}";
            }
            return null; // Pass on to next formatter or lastly DefaultResourceFormatter
        }
    },
    new class extends AbstractFormatter implements ResourceFormatterInterface
    {
        /**
         * @inheritDoc
         */
        public function format($resource): ?string
        {
            if (false == is_resource($resource)) {
                return null; // Pass on to next formatter or lastly DefaultResourceFormatter
            }
            if ("xml" === get_resource_type($resource)) {
                return "XML {$resource}";
            }
            return null; // Pass on to next formatter or lastly DefaultResourceFormatter
        }
    },
]));

echo $customTypeFormatter->cast(fopen(__FILE__, "r+")) . PHP_EOL;

/**
 * Will output:
 * opendir/fopen/tmpfile/popen/fsockopen/pfsockopen Resource id #<id>
 */

echo $customTypeFormatter->cast(\xml_parser_create("UTF-8")) . PHP_EOL;

/**
 * Will output:
 * XML Resource id #<id>
 */

Custom string formatter

<?php
use Kafoso\TypeFormatter\Abstraction\Type\AbstractFormatter;
use Kafoso\TypeFormatter\Collection\Type\StringFormatterCollection;
use Kafoso\TypeFormatter\Encoding;
use Kafoso\TypeFormatter\Type\StringFormatterInterface;
use Kafoso\TypeFormatter\TypeFormatter;

$customTypeFormatter = TypeFormatter::create();
$customTypeFormatter = $customTypeFormatter->withCustomStringFormatterCollection(new StringFormatterCollection([
    new class extends AbstractFormatter implements StringFormatterInterface
    {
        /**
         * @inheritDoc
         */
        public function format(string $string): ?string
        {
            if ("What do we like?" === $string) {
                return $this->getTypeFormatter()->getDefaultStringFormatter()->format("CAKE!");
            }
            return null; // Pass on to next formatter or lastly DefaultStringFormatter
        }
    },
]));

echo $customTypeFormatter->cast("What do we like?") . PHP_EOL;

/**
 * Will output:
 * "CAKE!"
 */

Tests

Unit tests (tests/tests/Test/Unit) will run on all environments that conform to the basic requirements.

Running tests

For all tests, first follow these steps:

Unit tests will run on most systems.

cd tests
php ../bin/phpunit tests/Test/Unit

Credits

Authors

• Kasper Søfren
  E-mail: [email protected]
  Homepage: https://github.com/kafoso