synopsis

PHP library to generate a language-agnostic description of PHP objects or values

Purpose

This library can be used to generate language-agnostic descriptions of PHP variables or objects that can then be sent over a transport to another system, e.g. for debugging, monitoring and inspection purposes.

It generates a standardised representation that can easily be formatted in different ways.

E.g. possible use-cases are

• sending data together with log messages to a logging service
• sending debug data to a debugging/inspection tool
• pretty-formatting exceptions including their traces and the arguments in the calls of those traces
• output data on different channels (e.g. terminal, web, etc.) via standardised formatters

Setup (via Composer)

Simply import the library in composer

composer require theiconic/synopsis

Basic Usage

You will need to start off by instantiating the factory

$factory = new TheIconic\Synopsis\Factory();

Now you can synopsise any value

class MyClass
{
    public $myProp = 1;
}

$myObject = new MyClass();
$myArray = [
    'string' => 'Hello World!',
    'integer' => 1,
    'boolean' = true,
];

$objectSynopsis = $factory->synopsize($myObject);
$arraySynopsis = $factory->synopsize($myArray);

Each call to synopsize() generates an AbstractSynopsis instance which describes the passed value.

Now use one of the formatters to format that data in a way that you can send over a transport or use by other components.

$formatter = new TheIconic\Synopsis\Formatter\ArrayFormatter();
$formatter->format($objectSynopsis);
/*
 * [
 *     'type' => 'MyClass',
 *     'length' => 1,
 *     'value' => ''
 *     'children' => [
 *         'myProp' => [
 *             'type' => 'integer',
 *             'length' => 1,
 *             'value' => 1,
 *         ]
 *     ]
 * ]
 */
 
$formatter->format($arraySynopsis);
/*
 * [
 *     'type' => 'array',
 *     'length' => 3,
 *     'value' => ''
 *     'children' => [
 *         'string' => [
 *             'type' => 'string',
 *             'length' => 12,
 *             'value' => 'Hello World!',
 *         ]
 *         'integer' => [
 *             'type' => 'integer',
 *             'length' => 1,
 *             'value' => 1,
 *         ],
 *         'string' => [
 *             'type' => 'boolean',
 *             'length' => 4,
 *             'value' => 'true',
 *         ]
 *     ]
 * ]
 */

Object Synopsis

When synopsising objects, the factory checks if a custom Synopsis class is registered for the type of the object (i.e. it's class name). If so, then the special Synopsis type is used to synopsise the object and the result entirely depends on its implementation.

Custom object types can be registered via

$factory->addObjectType(MyClass::$class, MyClassSynopsis::class);

If no custom type is registered, default object synopsis is used.

A custom IteratorSynopsis type is registered for objects that implement Iterator or IteratorAggregate interfaces.

Default Object Synopsis

The default ObjectSynopsis implementation will inspect the object for any public properties. Each of those properties will be treated as the objects children and synopsised recursively.

The length will be the number of public properties found.

The objects class name will be used as the type.

To determine the value, the implementation will check for the presence and accessibility of any of the following methods in this order

• __toSynopsisValue
• __toString
• getId
• getName

The first method found will be executed and it's return value will be cast to string and used as the objects value.

Default Iterator Synopsis

The default IteratorSynopsis implementation will iterate through the object, synopsise any of the iteration values and add them as children.

Resource Synopsis

When synopsising PHP resource pointers, the factory checks if a custom Synopsis class is registered for the type of resource (determined via get_resource_type()). If so, that type will be used.

By default, custom resource types are registered for some filetypes and streams and they will use stream_get_meta_data() to determine the resource uri and use it as the value.

Custom resource types can be registered via

$factory->addResourceType(MyClass::$class, MyClassSynopsis::class);

Exception Synopsis

Exceptions and their traces are synopsised in a special way adding additional properties to the synopsis objects.

These can be utilised in special Exception formatters.

ExceptionSynopsis

• type: the exception type
• value: the exception message
• length: the length of the stack trace
• line: the line
• file: the file
• children: the synopsised stack trace

TraceSynopsis

• type: a string representation of the full call
• value: a string representation of the file and line
• length: the number of call parameters
• line: the line
• file: the file
• class: the class name
• function: the function/method name
• children: the synopsised call parameters (if any)

Overriding default Synopsis implementations

To override the behaviour for any of the types, simply implement your own Synopsis class (inheriting from AbstractSynopsis) and register it with the factory via e.g.

$factory->addType('string', MyStringSynopsis::class);

License

THE ICONIC Synopsis library for PHP is released under the MIT License.