Complex classes like Schema often do a lot of different things. To break such a class down, we need to identify a cohesive component within that class. A common approach to find such a component is to look for fields/methods that share the same prefixes, or suffixes. You can also have a look at the cohesion graph to spot any un-connected, or weakly-connected components.
Once you have determined the fields that belong together, you can apply the Extract Class refactoring. If the component makes sense as a sub-class, Extract Subclass is also a candidate, and is often faster.
While breaking up the class, it is a good idea to analyze how other classes use Schema, and based on these observations, apply Extract Interface, too.
| 1 | <?php | ||
| 13 | class Schema implements \JsonSerializable { | ||
| 14 | /** | ||
| 15 | * Trigger a notice when extraneous properties are encountered during validation. | ||
| 16 | */ | ||
| 17 | const VALIDATE_EXTRA_PROPERTY_NOTICE = 0x1; | ||
| 18 | |||
| 19 | /** | ||
| 20 | * Throw a ValidationException when extraneous properties are encountered during validation. | ||
| 21 | */ | ||
| 22 | const VALIDATE_EXTRA_PROPERTY_EXCEPTION = 0x2; | ||
| 23 | |||
| 24 | /** | ||
| 25 | * @var array All the known types. | ||
| 26 | * | ||
| 27 | * If this is ever given some sort of public access then remove the static. | ||
| 28 | */ | ||
| 29 | private static $types = [ | ||
| 30 | 'array' => ['a'], | ||
| 31 | 'object' => ['o'], | ||
| 32 | 'integer' => ['i', 'int'], | ||
| 33 | 'string' => ['s', 'str'], | ||
| 34 | 'number' => ['f', 'float'], | ||
| 35 | 'boolean' => ['b', 'bool'], | ||
| 36 | 'timestamp' => ['ts'], | ||
| 37 | 'datetime' => ['dt'], | ||
| 38 | 'null' => ['n'] | ||
| 39 | ]; | ||
| 40 | |||
| 41 | private $schema = []; | ||
| 42 | |||
| 43 | /** | ||
| 44 | * @var int A bitwise combination of the various **Schema::FLAG_*** constants. | ||
| 45 | */ | ||
| 46 | private $flags = 0; | ||
| 47 | |||
| 48 | /** | ||
| 49 | * @var array An array of callbacks that will custom validate the schema. | ||
| 50 | */ | ||
| 51 | private $validators = []; | ||
| 52 | |||
| 53 | /** | ||
| 54 | * @var string|Validation The name of the class or an instance that will be cloned. | ||
| 55 | */ | ||
| 56 | private $validationClass = Validation::class; | ||
| 57 | |||
| 58 | |||
| 59 | /// Methods /// | ||
| 60 | |||
| 61 | /** | ||
| 62 |      * Initialize an instance of a new {@link Schema} class. | ||
| 63 | * | ||
| 64 | * @param array $schema The array schema to validate against. | ||
| 65 | */ | ||
| 66 | 142 |     public function __construct($schema = []) { | |
| 69 | |||
| 70 | /** | ||
| 71 | * Grab the schema's current description. | ||
| 72 | * | ||
| 73 | * @return string | ||
| 74 | */ | ||
| 75 | 1 |     public function getDescription() { | |
| 78 | |||
| 79 | /** | ||
| 80 | * Set the description for the schema. | ||
| 81 | * | ||
| 82 | * @param string $description The new description. | ||
| 83 | * @throws \InvalidArgumentException Throws an exception when the provided description is not a string. | ||
| 84 | * @return Schema | ||
| 85 | */ | ||
| 86 | 2 |     public function setDescription($description) { | |
| 95 | |||
| 96 | /** | ||
| 97 | * Return the validation flags. | ||
| 98 | * | ||
| 99 | * @return int Returns a bitwise combination of flags. | ||
| 100 | */ | ||
| 101 | 1 |     public function getFlags() { | |
| 104 | |||
| 105 | /** | ||
| 106 | * Set the validation flags. | ||
| 107 | * | ||
| 108 | * @param int $flags One or more of the **Schema::FLAG_*** constants. | ||
| 109 | * @return Schema Returns the current instance for fluent calls. | ||
| 110 | */ | ||
| 111 | 8 |     public function setFlags($flags) { | |
| 119 | |||
| 120 | /** | ||
| 121 | * Whether or not the schema has a flag (or combination of flags). | ||
| 122 | * | ||
| 123 | * @param int $flag One or more of the **Schema::VALIDATE_*** constants. | ||
| 124 | * @return bool Returns **true** if all of the flags are set or **false** otherwise. | ||
| 125 | */ | ||
| 126 | 8 |     public function hasFlag($flag) { | |
| 129 | |||
| 130 | /** | ||
| 131 | * Set a flag. | ||
| 132 | * | ||
| 133 | * @param int $flag One or more of the **Schema::VALIDATE_*** constants. | ||
| 134 | * @param bool $value Either true or false. | ||
| 135 | * @return $this | ||
| 136 | */ | ||
| 137 | 1 |     public function setFlag($flag, $value) { | |
| 145 | |||
| 146 | /** | ||
| 147 | * Merge a schema with this one. | ||
| 148 | * | ||
| 149 | * @param Schema $schema A scheme instance. Its parameters will be merged into the current instance. | ||
| 150 | */ | ||
| 151 | 2 |     public function merge(Schema $schema) { | |
| 175 | |||
| 176 | /** | ||
| 177 | * Returns the internal schema array. | ||
| 178 | * | ||
| 179 | * @return array | ||
| 180 | * @see Schema::jsonSerialize() | ||
| 181 | */ | ||
| 182 | 11 |     public function getSchemaArray() { | |
| 185 | |||
| 186 | /** | ||
| 187 | * Parse a schema in short form into a full schema array. | ||
| 188 | * | ||
| 189 | * @param array $arr The array to parse into a schema. | ||
| 190 | * @return array The full schema array. | ||
| 191 | * @throws \InvalidArgumentException Throws an exception when an item in the schema is invalid. | ||
| 192 | */ | ||
| 193 | 142 |     protected function parse(array $arr) { | |
| 225 | |||
| 226 | /** | ||
| 227 | * Parse a schema node. | ||
| 228 | * | ||
| 229 | * @param array $node The node to parse. | ||
| 230 | * @param mixed $value Additional information from the node. | ||
| 231 | * @return array Returns a JSON schema compatible node. | ||
| 232 | */ | ||
| 233 | 137 |     private function parseNode($node, $value = null) { | |
| 280 | |||
| 281 | /** | ||
| 282 | * Parse the schema for an object's properties. | ||
| 283 | * | ||
| 284 | * @param array $arr An object property schema. | ||
| 285 | * @return array Returns a schema array suitable to be placed in the **properties** key of a schema. | ||
| 286 | */ | ||
| 287 | 87 |     private function parseProperties(array $arr) { | |
| 313 | |||
| 314 | /** | ||
| 315 | * Parse a short parameter string into a full array parameter. | ||
| 316 | * | ||
| 317 | * @param string $key The short parameter string to parse. | ||
| 318 | * @param array $value An array of other information that might help resolve ambiguity. | ||
| 319 | * @return array Returns an array in the form `[string name, array param, bool required]`. | ||
| 320 | * @throws \InvalidArgumentException Throws an exception if the short param is not in the correct format. | ||
| 321 | */ | ||
| 322 | 135 |     public function parseShortParam($key, $value = []) { | |
| 380 | |||
| 381 | /** | ||
| 382 | * Add a custom validator to to validate the schema. | ||
| 383 | * | ||
| 384 | * @param string $fieldname The name of the field to validate, if any. | ||
| 385 | * | ||
| 386 | * If you are adding a validator to a deeply nested field then separate the path with dots. | ||
| 387 | * @param callable $callback The callback to validate with. | ||
| 388 | * @return Schema Returns `$this` for fluent calls. | ||
| 389 | */ | ||
| 390 | 2 |     public function addValidator($fieldname, callable $callback) { | |
| 394 | |||
| 395 | /** | ||
| 396 | * Require one of a given set of fields in the schema. | ||
| 397 | * | ||
| 398 | * @param array $required The field names to require. | ||
| 399 | * @param string $fieldname The name of the field to attach to. | ||
| 400 | * @param int $count The count of required items. | ||
| 401 | * @return Schema Returns `$this` for fluent calls. | ||
| 402 | */ | ||
| 403 | 1 |     public function requireOneOf(array $required, $fieldname = '', $count = 1) { | |
| 452 | |||
| 453 | /** | ||
| 454 | * Validate data against the schema. | ||
| 455 | * | ||
| 456 | * @param mixed $data The data to validate. | ||
| 457 | * @param bool $sparse Whether or not this is a sparse validation. | ||
| 458 | * @return mixed Returns a cleaned version of the data. | ||
| 459 | * @throws ValidationException Throws an exception when the data does not validate against the schema. | ||
| 460 | */ | ||
| 461 | 116 |     public function validate($data, $sparse = false) { | |
| 477 | |||
| 478 | /** | ||
| 479 | * Validate data against the schema and return the result. | ||
| 480 | * | ||
| 481 | * @param mixed $data The data to validate. | ||
| 482 | * @param bool $sparse Whether or not to do a sparse validation. | ||
| 483 | * @return bool Returns true if the data is valid. False otherwise. | ||
| 484 | */ | ||
| 485 | 33 |     public function isValid($data, $sparse = false) { | |
| 493 | |||
| 494 | /** | ||
| 495 | * Validate a field. | ||
| 496 | * | ||
| 497 | * @param mixed $value The value to validate. | ||
| 498 | * @param ValidationField $field A validation object to add errors to. | ||
| 499 | * @param bool $sparse Whether or not this is a sparse validation. | ||
| 500 | * @return mixed|Invalid Returns a clean version of the value with all extra fields stripped out or invalid if the value | ||
| 501 | * is completely invalid. | ||
| 502 | */ | ||
| 503 | 116 |     protected function validateField($value, ValidationField $field, $sparse = false) { | |
| 561 | |||
| 562 | /** | ||
| 563 | * Validate an array. | ||
| 564 | * | ||
| 565 | * @param mixed $value The value to validate. | ||
| 566 | * @param ValidationField $field The validation results to add. | ||
| 567 | * @param bool $sparse Whether or not this is a sparse validation. | ||
| 568 | * @return array|Invalid Returns an array or invalid if validation fails. | ||
| 569 | */ | ||
| 570 | 12 |     protected function validateArray($value, ValidationField $field, $sparse = false) { | |
| 600 | |||
| 601 | /** | ||
| 602 | * Validate a boolean value. | ||
| 603 | * | ||
| 604 | * @param mixed $value The value to validate. | ||
| 605 | * @param ValidationField $field The validation results to add. | ||
| 606 | * @return bool|Invalid Returns the cleaned value or invalid if validation fails. | ||
| 607 | */ | ||
| 608 | 21 |     protected function validateBoolean($value, ValidationField $field) { | |
| 609 | 21 | $value = $value === null ? $value : filter_var($value, FILTER_VALIDATE_BOOLEAN, FILTER_NULL_ON_FAILURE); | |
| 610 | 21 |         if ($value === null) { | |
| 611 | 5 |             $field->addTypeError('boolean'); | |
| 612 | 5 | return Invalid::value(); | |
| 613 | } | ||
| 614 | 17 | return $value; | |
| 615 | } | ||
| 616 | |||
| 617 | /** | ||
| 618 | * Validate a date time. | ||
| 619 | * | ||
| 620 | * @param mixed $value The value to validate. | ||
| 621 | * @param ValidationField $field The validation results to add. | ||
| 622 | * @return \DateTimeInterface|Invalid Returns the cleaned value or **null** if it isn't valid. | ||
| 623 | */ | ||
| 624 | 13 |     protected function validateDatetime($value, ValidationField $field) { | |
| 649 | |||
| 650 | /** | ||
| 651 | * Validate a float. | ||
| 652 | * | ||
| 653 | * @param mixed $value The value to validate. | ||
| 654 | * @param ValidationField $field The validation results to add. | ||
| 655 | * @return float|Invalid Returns a number or **null** if validation fails. | ||
| 656 | */ | ||
| 657 | 9 |     protected function validateNumber($value, ValidationField $field) { | |
| 665 | |||
| 666 | /** | ||
| 667 | * Validate and integer. | ||
| 668 | * | ||
| 669 | * @param mixed $value The value to validate. | ||
| 670 | * @param ValidationField $field The validation results to add. | ||
| 671 | * @return int|Invalid Returns the cleaned value or **null** if validation fails. | ||
| 672 | */ | ||
| 673 | 22 |     protected function validateInteger($value, ValidationField $field) { | |
| 682 | |||
| 683 | /** | ||
| 684 | * Validate an object. | ||
| 685 | * | ||
| 686 | * @param mixed $value The value to validate. | ||
| 687 | * @param ValidationField $field The validation results to add. | ||
| 688 | * @param bool $sparse Whether or not this is a sparse validation. | ||
| 689 | * @return object|Invalid Returns a clean object or **null** if validation fails. | ||
| 690 | */ | ||
| 691 | 76 |     protected function validateObject($value, ValidationField $field, $sparse = false) { | |
| 701 | |||
| 702 | /** | ||
| 703 | * Validate data against the schema and return the result. | ||
| 704 | * | ||
| 705 | * @param array $data The data to validate. | ||
| 706 | * @param ValidationField $field This argument will be filled with the validation result. | ||
| 707 | * @param bool $sparse Whether or not this is a sparse validation. | ||
| 708 | * @return array|Invalid Returns a clean array with only the appropriate properties and the data coerced to proper types. | ||
| 709 | * or invalid if there are no valid properties. | ||
| 710 | */ | ||
| 711 | 75 |     protected function validateProperties(array $data, ValidationField $field, $sparse = false) { | |
| 763 | |||
| 764 | /** | ||
| 765 | * Validate a string. | ||
| 766 | * | ||
| 767 | * @param mixed $value The value to validate. | ||
| 768 | * @param ValidationField $field The validation results to add. | ||
| 769 | * @return string|Invalid Returns the valid string or **null** if validation fails. | ||
| 770 | */ | ||
| 771 | 51 |     protected function validateString($value, ValidationField $field) { | |
| 860 | |||
| 861 | /** | ||
| 862 | * Validate a unix timestamp. | ||
| 863 | * | ||
| 864 | * @param mixed $value The value to validate. | ||
| 865 | * @param ValidationField $field The field being validated. | ||
| 866 | * @return int|Invalid Returns a valid timestamp or invalid if the value doesn't validate. | ||
| 867 | */ | ||
| 868 | 8 |     protected function validateTimestamp($value, ValidationField $field) { | |
| 879 | |||
| 880 | /** | ||
| 881 | * Validate a null value. | ||
| 882 | * | ||
| 883 | * @param mixed $value The value to validate. | ||
| 884 | * @param ValidationField $field The error collector for the field. | ||
| 885 | * @return null|Invalid Returns **null** or invalid. | ||
| 886 | */ | ||
| 887 |     protected function validateNull($value, ValidationField $field) { | ||
| 894 | |||
| 895 | /** | ||
| 896 | * Validate a value against an enum. | ||
| 897 | * | ||
| 898 | * @param mixed $value The value to test. | ||
| 899 | * @param ValidationField $field The validation object for adding errors. | ||
| 900 | * @return mixed|Invalid Returns the value if it is one of the enumerated values or invalid otherwise. | ||
| 901 | */ | ||
| 902 | 114 |     protected function validateEnum($value, ValidationField $field) { | |
| 921 | |||
| 922 | /** | ||
| 923 | * Call all of the validators attached to a field. | ||
| 924 | * | ||
| 925 | * @param mixed $value The field value being validated. | ||
| 926 | * @param ValidationField $field The validation object to add errors. | ||
| 927 | */ | ||
| 928 | 114 |     protected function callValidators($value, ValidationField $field) { | |
| 948 | |||
| 949 | /** | ||
| 950 | * Specify data which should be serialized to JSON. | ||
| 951 | * | ||
| 952 | * This method specifically returns data compatible with the JSON schema format. | ||
| 953 | * | ||
| 954 | * @return mixed Returns data which can be serialized by **json_encode()**, which is a value of any type other than a resource. | ||
| 955 | * @link http://php.net/manual/en/jsonserializable.jsonserialize.php | ||
| 956 | * @link http://json-schema.org/ | ||
| 957 | */ | ||
| 958 |     public function jsonSerialize() { | ||
| 993 | |||
| 994 | /** | ||
| 995 | * Look up a type based on its alias. | ||
| 996 | * | ||
| 997 | * @param string $alias The type alias or type name to lookup. | ||
| 998 | * @return mixed | ||
| 999 | */ | ||
| 1000 | 132 |     protected function getType($alias) { | |
| 1011 | |||
| 1012 | /** | ||
| 1013 | * Get the class that's used to contain validation information. | ||
| 1014 | * | ||
| 1015 | * @return Validation|string Returns the validation class. | ||
| 1016 | */ | ||
| 1017 | 116 |     public function getValidationClass() { | |
| 1020 | |||
| 1021 | /** | ||
| 1022 | * Set the class that's used to contain validation information. | ||
| 1023 | * | ||
| 1024 | * @param Validation|string $class Either the name of a class or a class that will be cloned. | ||
| 1025 | * @return $this | ||
| 1026 | */ | ||
| 1027 | 1 |     public function setValidationClass($class) { | |
| 1035 | |||
| 1036 | /** | ||
| 1037 | * Create a new validation instance. | ||
| 1038 | * | ||
| 1039 | * @return Validation Returns a validation object. | ||
| 1040 | */ | ||
| 1041 | 116 |     protected function createValidation() { | |
| 1051 | } | ||
| 1052 | 
This check looks for multiple assignments in successive lines of code. It will report an issue if the operators are not in a straight line.
To visualize
will produce issues in the first and second line, while this second example
will produce no issues.