Group Middleware – Implement in stand alone php scripts

Group middleware is a way to bundle multiple middleware under one group name, so you don’t have to manually list every single middleware for every route.

Instead of this:

['checkAge', 'checkRole', 'logRequest']

You can do:

['authGroup']

Where authGroup is mapped to those three middleware.

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🧱 Example in Laravel-style

In Laravel:

Route::middleware(['authGroup'])->group(function () {
    // routes here
});

Where in Kernel.php:

'authGroup' => [
    \App\Http\Middleware\CheckAge::class,
    \App\Http\Middleware\CheckRole::class,
    \App\Http\Middleware\LogRequest::class,
],

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✅ Let’s Implement Group Middleware in Your Custom System

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📁 Step-by-step Structure Recap

We’ll enhance your current setup by adding:

✅ Middleware registry
✅ Group definitions
✅ Logic to resolve group names into middleware arrays

You can check my private git repo here to see working example.

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✅ Step 1: Middleware definitions

$checkAge = function ($request, Closure $next) {
    if ($request['age'] < 18) {
        return "You must be 18+";
    }
    return $next($request);
};

$checkRole = function ($request, Closure $next) {
    if ($request['role'] !== 'admin') {
        return "Access denied. Admins only.";
    }
    return $next($request);
};

$logRequest = function ($request, Closure $next) {
    echo "Logging request...\n";
    return $next($request);
};

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✅ Step 2: Middleware Group Registry

$middlewareGroups = [
    'authGroup' => [
        'checkAge',
        'checkRole',
        'logRequest',
    ],
];

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✅ Step 3: Middleware Lookup Table (by name)

$middlewareMap = [
    'checkAge' => $checkAge,
    'checkRole' => $checkRole,
    'logRequest' => $logRequest,
];

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✅ Step 4: Group Resolver Function

The group resolver builds a final array of middleware functions that will be passed into the pipeline (defined in the manager file).

function resolveMiddlewares(array $middlewares, array $groups, array $map) {
    $resolved = [];

    foreach ($middlewares as $key) {
        if (isset($groups[$key])) {
            foreach ($groups[$key] as $grouped) {
                $resolved[] = $map[$grouped];
            }
        } elseif (isset($map[$key])) {
            $resolved[] = $map[$key];
        }
    }

    return $resolved;
}

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✅ Step 5: Controller

$controller = function ($request) {
    return "Welcome, {$request['user']}!";
};

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✅ Step 6: Pipeline Builder (same as before)

function buildPipeline(array $middlewares, Closure $controller)
{
    return array_reduce(
        array_reverse($middlewares),
        function ($next, $middleware) {
            return function ($request) use ($middleware, $next) {
                return $middleware($request, $next);
            };
        },
        $controller
    );
}

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✅ Step 7: Simulate Router / Request

$request = [
    'user' => 'Dilip',
    'age' => 22,
    'role' => 'admin'
];

// Middleware group to apply
$routeMiddleware = ['authGroup']; // could also be ['checkAge', 'logRequest']

$resolvedMiddleware = resolveMiddlewares($routeMiddleware, $middlewareGroups, $middlewareMap);

$pipeline = buildPipeline($resolvedMiddleware, $controller);
$response = $pipeline($request);

echo $response;

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🧪 Sample Output:

Logging request...
Welcome, Dilip!

(Change role to user, and you’ll see: Access denied. Admins only.)

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✅ Final Summary: Middleware Group in Your Mini PHP App

Concept	Code Element
Middleware	$checkAge, $checkRole, $logRequest
Group definition	$middlewareGroups['authGroup']
Name mapping	$middlewareMap
Resolver function	resolveMiddlewares()
Pipeline executor	buildPipeline()
Entry point	Simulated “route” that applies a group

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🏙️ Middleware Group Analogy in a Multi-Lift Building

🛗 Scenario:

Imagine the Burj Khalifa — it’s a very tall building, so it doesn’t have just one lift.
Instead, it has lift zones, like:

• Lift A: Floors 1–20
• Lift B: Floors 21–50
• Lift C: Floors 51–100

Each lift services a specific group of floors.

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🔁 Mapping to Middleware Groups

Building Concept	Middleware System Equivalent
Multi-floor building	Your application / route system
Lift Zones (A, B, C)	Middleware Groups (web, api, authGroup)
Floor buttons in a lift	Individual middleware in that group
Passenger	The incoming request
Final floor destination	The controller / final response

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✅ Example

Let’s say you’re in Lift B (Floors 21–50). It always goes through:

• Floor 21: checkAge
• Floor 25: checkRole
• Floor 40: logRequest
• Floor 50: Final destination (controller)

This Lift B is your authGroup middleware group in Laravel.

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🧠 Why is this powerful?

Instead of defining all individual floor stops every time, you can just say:

“This route takes Lift B (authGroup)”
Laravel (or your manager) will know:

• Which floor stops (middlewares) to include
• In what order
• And how to pass the request from one to another

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✅ Analogy Summary

In a super-tall building, lifts are grouped to handle certain floor ranges.
Similarly, in your app, middleware groups are bundled sets of middleware to handle related tasks — like auth, logging, throttling, etc.
You assign a route to a group lift, and it stops at the right middleware floors automatically.

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🧾 Real Laravel Mapping

'authGroup' => [
    'checkAge',
    'checkRole',
    'logRequest'
];

Route::middleware(['authGroup'])->get('/dashboard', fn() => 'Dashboard');

👆 Laravel knows:
“This request takes Lift B — so it should stop at those floors before reaching the controller.”

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