README

A straightforward, type-safe HTTP response builder for PHP. Build and send HTTP responses with proper headers, cache control, content types, and status codes. Designed to minimize footguns, maximize productivity, and provide useful hinting and IntelliSense features in your IDE.

Features:

• Type-safe response building with fluent interfaces
• First-class cache control headers
• Automatic content type detection and charset handling
• Range request support for efficient streaming
• Built-in content types: strings, JSON, files, callbacks, and empty responses
• Requires PHP 8.4+

Installation

composer require joby/smol-response

Quick Start

use Joby\Smol\Response\Response;

// Simple text response
$response = new Response(200, 'Hello World');

// JSON response
$response = Response::json(['status' => 'ok', 'data' => $results]);

// File download
$response = Response::file('/path/to/file.pdf');

// Redirect
$response = Response::redirect('https://example.com', permanent: true);

// Render the response
$renderer = new \Joby\Smol\Response\Renderer();
$renderer->render($response);

Core Components

Response (Response)

The main response builder. Create responses with various content types and configurations.

Factory Methods:

• json($data, $status = 200) - Create JSON response
• file($path, $status = 200) - Create file response
• redirect($url, $permanent = false, $preserve_method = false) - Create redirect response

Fluent Methods:

$response = (new Response(201, 'Created'))
    ->cachePublicContent()
    ->setStatus(200);

Status (Status)

Type-safe HTTP status codes with standard reason phrases:

$status = new Status(404);
echo $status->code;           // 404
echo $status->reason_phrase;  // "Not Found"

Cache Control (CacheControl)

First-class cache control with support for modern caching strategies:

Presets:

• publicContent($max_age = 300, $max_stale_age = 86400) - Public HTML pages
• publicMedia($max_age = 31536000, $max_stale_age = 31536000) - Public static assets
• privateContent($max_age = 300, $max_stale_age = 600) - Private HTML pages
• privateMedia($max_age = 31536000, $max_stale_age = 31536000) - Private static assets
• neverCached() - No caching (CSRF forms, CAPTCHAs)

$response->cache = CacheControl::publicMedia();
// Renders: public, max-age=31536000, s-maxage=31536000, 
//          stale-while-revalidate=31536000, stale-if-error=31536000

$response->cachePublicContent(); // Fluent helper method

Headers (Headers)

Normalized header collection with automatic header name formatting:

$response->headers['content-type'] = 'application/json';
$response->headers['X-Custom-Header'] = 'value';

// Headers are automatically normalized to proper case
foreach ($response->headers as $name => $value) {
    echo "$name: $value\n";
    // Content-Type: application/json
    // X-Custom-Header: value
}

Content Types

All content types implement ContentInterface with automatic metadata handling.

StringContent

For text and HTML content:

$content = new StringContent('<h1>Hello World</h1>');
$content->setFilename('page.html');
$response->content = $content;

CallbackContent

For dynamic content generation with callbacks:

// Simple callback
$content = new CallbackContent(function() {
    echo renderTemplate('page.html', ['title' => 'Welcome']);
});

// With external data
$data = fetchDataFromDatabase();
$content = new CallbackContent(function() use ($data) {
    foreach ($data as $item) {
        echo "<li>{$item->name}</li>";
    }
});

// Supports any callable type
$content = new CallbackContent([$templateEngine, 'render']);
$content->setFilename('output.html');
$response->content = $content;

JsonContent

For JSON responses:

$content = new JsonContent(['status' => 'ok', 'items' => $items]);
$response->content = $content;

FileContent

For serving files with automatic MIME detection:

$content = new FileContent('/path/to/file.pdf');
$response->content = $content;

EmptyContent

For responses with no body:

$response = new Response(204, new EmptyContent());

Advanced Features

Range Requests

Efficiently serve partial content for video streaming and resumable downloads:

// Content automatically supports range requests
$content = new FileContent('/path/to/video.mp4');

// Apply a range manually
$ranged = new AppliedRangeContent($content, 0, 1024);
$response->content = $ranged;

// Renderer automatically sets 206 status and Content-Range header

Custom Content Types

Create your own content types by implementing ContentInterface or extending AbstractContent:

class TemplateContent extends AbstractContent
{
    public function __construct(private string $template, private array $data) {
        $this->filename = 'page.html';
    }
    
    public function render(): void {
        echo $this->engine->render($this->template, $this->data);
    }
    
    public function size(): int|null {
        return null; // Unknown until rendered
    }
}

Response Rendering

The Renderer handles all HTTP output:

$renderer = new Renderer();
$renderer->render($response);

// Or test header generation without sending
$headers = $renderer->buildHeaders($response);

Automatic Header Generation:

• Content-Type with charset for text content
• Content-Length for known-size content
• Content-Disposition with filename for downloads
• ETag from content hashes
• Last-Modified from file modification times
• Accept-Ranges for range-capable content
• Content-Range for partial content responses

Fluent Response Building

Chain methods for readable response construction:

$response = Response::json($data)
    ->setStatus(201)
    ->cachePublicContent();

$response->headers['Location'] = '/api/resource/123';

Content Metadata

All content types provide rich metadata:

echo $content->filename();       // 'document.pdf'
echo $content->mime();           // 'application/pdf'
echo $content->contentType();    // 'application/pdf'
echo $content->size();           // File size in bytes
echo $content->etag();           // MD5 hash for caching
echo $content->lastModified();   // DateTime of last modification

Use Cases

Static File Router

Build a simple static file server with aggressive caching:

$path = '/var/www/public' . $_SERVER['REQUEST_URI'];

if (file_exists($path)) {
    $response = Response::file($path)->cachePublicMedia();
    (new Renderer())->render($response);
}

API Responses

Consistent JSON API responses:

function apiSuccess($data, $code = 200) {
    return Response::json(['success' => true, 'data' => $data], $code)
        ->cacheNever();
}

function apiError($message, $code = 400) {
    return Response::json(['success' => false, 'error' => $message], $code)
        ->cacheNever();
}

Content Transformations

Transform content before serving:

$djot = file_get_contents('content.djot');
$html = renderDjotToHtml($djot);

$response = (new Response(200, $html))
    ->cachePublicContent();

$response->headers['Content-Type'] = 'text/html; charset=UTF-8';

Dynamic Content Generation

Use callbacks for complex rendering logic:

// Template rendering with caching
$response = new Response(200, new CallbackContent(function() use ($templateEngine, $data) {
    echo $templateEngine->render('dashboard.html', $data);
}));
$response->cachePublicContent();

// Streaming output
$response = new Response(200, new CallbackContent(function() {
    foreach (generateLargeDataset() as $chunk) {
        echo json_encode($chunk) . "\n";
    }
}));