Insisting on correct data makes every chunk of code a little happier.

By relying on json-schema, Insistence is a powerful utility to apply complex yet flexible constraints on handled data. Insistence uses the popular justinrainbow/json-schema as foundation.

In addition to the generic constraints specified by JSON-schema, there is two PHP specific constrains that can be used.

The following internalTypes is available, their usage should be obvious for a PHP programmer.

• boolean
• integer
• float
• string
• array
• object
• resource
• null
• numeric
• callable
• scalar

Some types support subtyping as well. One or more subtypes may be added after the main type.

• array-access — Accepts ArrayAccess as well as standard arrays
• array-indexed — Requires that the array only uses sequential, integer keys starting with 0
• array-associative — Requires that the array only uses strings for keys

The internalType constraint accepts either a string, or an array of strings where at least one must match to succeed the constraint.

Examples;

$insistence = new Insistence(['internalType' => 'string']);
$insistence = new Insistence(['internalType' => 'array-associative']);
$insistence = new Insistence(['internalType' => 'array-access-indexed']);
$insistence = new Insistence(['internalType' => ['object', 'null']]);

The instanceOf constraint accepts either a string, or an array of strings where at least one must match to succeed the constraint.

It may only be used on data of PHP type "object".

$insistence = new Insistence(['internalType' => 'float', 'min' => 1.0, 'max' => 9.9]);
$insistence->insist(4.45); // Will pass
$insistence->insist(123.45); // Will fail, higher then max 9.9
$insistence->insist("Hello"); // Will fail, not a float

The trait serves as a convenience wrapper to use Insistence in any class.

class MyClass
{
    use \Phrity\Util\InsistenceTrait;

    public function myMethod($some_data)
    {
        // Will fail if not a string with at least 8 characters
        $this->insist(['type' => 'string', 'minlength' => 8], $some_data);

        $some_result = some_method(20);
        // Will fail if result is not an object or null
        $this->insist(['internalType' => ['object', 'null']], $some_result);
    }
}