⚙️ Ruleset Engine

The Ruleset Engine is a straightforward filtering strategy that interprets filters as flat rule arrays. It's especially suitable for simple request formats, where each filter targets a specific field using one or more operators.

This engine is ideal for APIs and frontends that send clean key-value pairs or use operator-based nesting.

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✅ When to Use

• When handling simple query structures like:

  GET /posts?filter[status]=pending&filter[name][like]=kettasoft
  

• When you prefer clear mapping of field-operator-value.
• When you want to use default operators for common fields without specifying one explicitly.

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🧩 How It Works

The engine accepts a request array structured as:

🔹 Format 1: Default operator (e.g. eq)

/posts?filter[status]=pending

This will be interpreted as:

['status' => ['eq' => 'pending']]

The default operator (eq) is configurable through the engine's options or Filterable settings.

🔹 Format 2: Custom operator

/posts?filter[name][like]=kettasoft

This will be interpreted as:

['name' => ['like' => 'kettasoft']]

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🛠 Operator Resolution

If an operator is not explicitly provided in the request, the default operator will be used.
This default can be set via the engine configuration.

'default_operator' => '='

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🧱 Supported Operators

Operator	SQL Equivalent	Example
eq	=	filter[status]=published
neq	!=	filter[status][neq]=draft
gt	>	filter[views][gt]=100
gte	>=	filter[created_at][gte]=2024-01-01
lt	<	filter[views][lt]=100
lte	<=	filter[views][lte]=50
like	LIKE	filter[title][like]=%laravel%
in	IN	filter[id][in][]=1&filter[id][in][]=2
between	BETWEEN	filter[price][between][]=100&filter[price][between][]=200

Operators are customizable and extendable. You may add your own by overriding the engine's resolver.

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🧪 Example Filter Class

use Kettasoft\Filterable\Filterable;

class PostFilter extends Filterable
{
    protected $allowdFields = ['status', 'title', 'published_at'];

    protected $allowdOperators = ['eq', 'like', 'gte']; // Allowed operators
}

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🔐 Security & Strict Mode

You can enforce strict filtering by enabling strict mode, which validates:

• That each filter field is allowed.
• That each operator is supported.
• That no unexpected or malicious keys are applied.

If any validation fails, an exception will be thrown instead of silently ignoring the input.

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🌿 Best Practices

• Always define allowed fields and allowed operators in your filter class.
• Use request validation or sanitizers to clean filter input before applying to query.
• Avoid exposing sensitive fields via filters unless explicitly allowed.