EmptyRequirementsList

Description

EmptyRequirementsList is an exception. It is thrown when the list of requirements passed into RequireAllOf or RequireAnyOneOf is an empty list.

Public Interface

EmptyRequirementsList has the following public interface:

// EmptyRequirementsList lives in this namespace
namespace GanbaroDigital\Defensive\V1\Exceptions;

// our base class and interface(s)
use GanbaroDigital\ExceptionHelpers\V1\BaseExceptions\ParameterisedException;
use GanbaroDigital\HttpStatus\Interfaces\HttpRequestErrorException;

// return types from our method(s)
use GanbaroDigital\HttpStatus\StatusValues\RequestError\UnprocessableEntityStatus;

class EmptyRequirementsList
  extends ParameterisedException
  implements DefensiveException, HttpRequestErrorException
{
    // we map onto HTTP 422
    use UnprocessableEntityStatusProvider;

    /**
     * create a new exception from the requirements list that has been
     * rejected
     *
     * @param  mixed $fieldOrVar
     *         the value that you're throwing an exception about
     * @param  string $fieldOrVarName
     *         the name of the value in your code
     * @param  array $extraData
     *         extra data that you want to include in your exception
     * @param  int|null $typeFlags
     *         do we want any extra type information in the final
     *         exception message?
     * @param  array $callStackFilter
     *         are there any namespaces we want to filter out of
     *         the call stack?
     * @return EmptyRequirementsList
     *         an fully-built exception for you to throw
     */
    public static function newFromVar(
        $fieldOrVar,
        $fieldOrVarName,
        array $extraData = [],
        $typeFlags = null,
        array $callStackFilter = []
    );

    /**
     * what was the data that we used to create the printable message?
     *
     * @return array
     */
    public function getMessageData();

    /**
     * what was the format string we used to create the printable message?
     *
     * @return string
     */
    public function getMessageFormat();

    /**
     * which HTTP status code do we map onto?
     *
     * @return UnprocessableEntityStatus
     */
    public function getHttpStatus();
}

How To Use

Creating Exceptions To Throw

Call EmptyRequirementsList::newFromVar() to create a new throwable exception:

// how to import
use GanbaroDigital\Defensive\V1\Exceptions\EmptyRequirementsList;

throw EmptyRequirementsList::newFromVar(null, '$list');

Catching The Exception

EmptyRequirementsList extends or implements a rich set of classes and interfaces. You can use any of these to catch thrown exceptions.

// example 1: we catch only EmptyRequirementsList exceptions
use GanbaroDigital\Defensive\V1\Exceptions\EmptyRequirementsList;

try {
    throw EmptyRequirementsList::newFromVar([], '$list');
}
catch(EmptyRequirementsList $e) {
    // ...
}

// example 2: catch all exceptions thrown by the Defensive Library
use GanbaroDigital\Defensive\V1\Exceptions\EmptyRequirementsList;
use GanbaroDigital\Defensive\V1\Exceptions\DefensiveException;

try {
    throw EmptyRequirementsList::newFromVar([], '$list');
}
catch(DefensiveException $e) {
    // ...
}

// example 3: catch all exceptions where there was a problem with the
// parameter(s) passed into the method
use GanbaroDigital\Defensive\V1\Exceptions\EmptyRequirementsList;
use GanbaroDigital\HttpStatus\Interfaces\HttpRequestErrorException;

try {
    throw EmptyRequirementsList::newFromVar([], '$list');
}
catch(HttpRequestErrorException $e) {
    $httpStatus = $e->getHttpStatus();
    // ...
}

// example 4: catch all exceptions that map onto a HTTP status
use GanbaroDigital\Defensive\V1\Exceptions\EmptyRequirementsList;
use GanbaroDigital\HttpStatus\Interfaces\HttpException;

try {
    throw EmptyRequirementsList::newFromVar([], '$list');
}
catch(HttpException $e) {
    $httpStatus = $e->getHttpStatus();
    // ...
}

// example 5: catch all runtime exceptions
use GanbaroDigital\Defensive\V1\Exceptions\EmptyRequirementsList;
use RuntimeException;

try {
    throw EmptyRequirementsList::newFromVar([], '$list');
}
catch(RuntimeException $e) {
    // ...
}

Class Contract

Here is the contract for this class:

GanbaroDigital\Defensive\V1\Exceptions\EmptyRequirementsList
 [x] Can instantiate
 [x] is DefensiveException
 [x] is RuntimeException
 [x] is HttpRequestErrorException
 [x] maps to HTTP 422 UnprocessableEntity
 [x] Can create from empty requirements list list
 [x] exception states that list must not be empty

Class contracts are built from this class's unit tests.

Notes

None at this time.

See Also

• ParameterisedException class
• mapping exceptions onto HTTP status codes