GeezerVison

PHP Rule Engine

Install

composer install nicoswd/php-rule-parser

Usage Examples

$variables = [
    'cart_total'     => 120,
    'user_tier'      => 'gold',
    'is_blacklisted' => false,
];

$rule = new Rule('
    cart_total >= 50 && 
    user_tier in ["gold", "platinum"] &&
    !is_blacklisted
', $variables);

var_dump($rule->isTrue()); // bool(true) — eligible for discount

$variables = [
    'role'         => 'editor',
    'is_suspended' => false,
];

$rule = new Rule('role in ["admin", "editor"] && !is_suspended', $variables);
var_dump($rule->isTrue()); // bool(true) — access granted

$variables = [
    'base_price' => 29.99,
    'tax_rate'   => 21,
    'quantity'   => 3,
];

$rule = new Rule('(base_price + (base_price * tax_rate / 100)) * quantity', $variables);
var_dump($rule->result()); // float(108.8571...) — total with tax

$variables = [
    'age'     => 25,
    'country' => 'US',
];

$rule = new Rule('age >= 18 && country in ["US", "CA", "UK"]', $variables);
var_dump($rule->isTrue()); // bool(true) — valid registration

$variables = [
    'plan'                 => 'pro',
    'last_login'           => 3,
    'notification_opt_out' => false,
];

$rule = new Rule('
    plan in ["pro", "enterprise"] &&
    last_login < 7 &&
    !notification_opt_out
', $variables);

var_dump($rule->isTrue()); // bool(true) — send notification

$variables = [
    'user_id' => 7,
];

$rule = new Rule('user_id % 10 < 3', $variables);
var_dump($rule->isTrue()); // bool(true) — feature enabled for this user

$variables = [
    'firstName' => 'John',
    'lastName'  => 'Doe',
];

$rule = new Rule('firstName.toUpperCase() + " " + lastName.toUpperCase()', $variables);
var_dump($rule->result()); // string("JOHN DOE")

class Subscription
{
    public function isActive(): bool
    {
        return true;
    }

    public function daysUntilExpiry(): int
    {
        return 15;
    }
}

$variables = [
    'subscription' => new Subscription(),
];

$rule = new Rule('subscription.isActive() && subscription.daysUntilExpiry() > 7', $variables);
var_dump($rule->isTrue()); // bool(true) — subscription is active and not expiring soon

$rule = new Rule('2 + 3 * 4 == 14');
var_dump($rule->isTrue()); // bool(true) - multiplication before addition

$rule = new Rule('(2 + 3) * 4 == 20');
var_dump($rule->isTrue()); // bool(true) - parentheses override precedence

$rule = new Rule('-5 * 3 == -15');
var_dump($rule->isTrue()); // bool(true) - unary minus

$rule = new Rule('!false');
var_dump($rule->isTrue()); // bool(true) - logical NOT

$rule = new Rule('!(1 == 2)');
var_dump($rule->isTrue()); // bool(true) - NOT with comparison

Note

For security reasons, PHP's magic methods like __construct and __destruct cannot be called from within rules. However, __call will be invoked automatically if available, unless the called method is defined.

Built-in Methods

Built-in Functions

Supported Operators

Error Handling

$ruleStr = '
    (2 == 2) && (
        1 < 3 && 3 == 2 ( // Missing and/or before parentheses
            1 == 1
        )
    )';

$rule = new Rule($ruleStr);

try {
    $rule->isTrue();
} catch (\Exception $e) {
    echo $e->getMessage();
}

if (!$rule->isValid()) {
    echo $rule->error;
}

Syntax Highlighting

use nicoSWD\Rule\Highlighter\Highlighter;
use nicoSWD\Rule\TokenStream\Token\TokenType;

$ruleStr = '
    // This is true
    2 < 3 && (
        // This is false
        foo in [4, 6, 7] ||
        // True
        [1, 4, 3].join("") === "143"
    ) && (
        // True
        "foo|bar|baz".split("|" /* uh oh */) === ["foo", /* what */ "bar", "baz"] &&
        // True
        bar > 6
    )';

$highlighter = new Highlighter();

// Optional custom styles
$highlighter->setStyle(
    TokenType::VARIABLE,
    'color: #007694; font-weight: 900;'
);

echo $highlighter->highlightString($ruleStr);

Security

Testing

$ composer test

Contributing

To Do

License