README

Fetch PHP is a modern HTTP client library for PHP that brings JavaScript's fetch API experience to PHP. Built on top of Guzzle, Fetch PHP allows you to write HTTP code with a clean, intuitive JavaScript-like syntax while still maintaining PHP's familiar patterns.

With support for both synchronous and asynchronous requests, a fluent chainable API, and powerful retry mechanics, Fetch PHP streamlines HTTP operations in your PHP applications.

Full documentation can be found here

Key Features

• JavaScript-like Syntax: Write HTTP requests just like you would in JavaScript with the fetch() function and async/await patterns
• Promise-based API: Use familiar .then(), .catch(), and .finally() methods for async operations
• Fluent Interface: Build requests with a clean, chainable API
• Built on Guzzle: Benefit from Guzzle's robust functionality with a more elegant API
• Retry Mechanics: Configurable retry logic with exponential backoff for transient failures
• RFC 7234 HTTP Caching: Full caching support with ETag/Last-Modified revalidation, stale-while-revalidate, and stale-if-error
• Connection Pooling: Reuse TCP connections across requests with global connection pool and DNS caching
• HTTP/2 Support: Native HTTP/2 protocol support for improved performance
• Debug & Profiling: Built-in debugging and performance profiling capabilities
• Type-Safe Enums: Modern PHP 8.3+ enums for HTTP methods, content types, and status codes
• Testing Utilities: Built-in mock responses and request recording for testing
• PHP-style Helper Functions: Includes traditional PHP function helpers (get(), post(), etc.) for those who prefer that style
• PSR Compliant: Implements PSR-7 (HTTP Messages), PSR-18 (HTTP Client), and PSR-3 (Logger) standards

Why Choose Fetch PHP?

Beyond Guzzle

While Guzzle is a powerful HTTP client, Fetch PHP enhances the experience by providing:

• JavaScript-like API: Enjoy the familiar fetch() API and async/await patterns from JavaScript
• Global client management: Configure once, use everywhere with the global client
• Simplified requests: Make common HTTP requests with less code
• Enhanced error handling: Reliable retry mechanics and clear error information
• Type-safe enums: Use enums for HTTP methods, content types, and status codes

Installation

composer require jerome/fetch-php

Requirements: PHP 8.3 or higher

Basic Usage

JavaScript-style API

// Simple GET request
$response = fetch('https://api.example.com/users');
$users = $response->json();

// POST request with JSON body
$response = fetch('https://api.example.com/users', [
    'method' => 'POST',
    'json' => ['name' => 'John Doe', 'email' => 'john@example.com'],
]);

PHP-style Helpers

// GET request with query parameters
$response = get('https://api.example.com/users', ['page' => 1, 'limit' => 10]);

// POST request with JSON data
$response = post('https://api.example.com/users', [
    'name' => 'John Doe',
    'email' => 'john@example.com'
]);

Fluent API

// Chain methods to build your request
$response = fetch_client()
    ->baseUri('https://api.example.com')
    ->withHeaders(['Accept' => 'application/json'])
    ->withToken('your-auth-token')
    ->withQueryParameters(['page' => 1, 'limit' => 10])
    ->get('/users');

Async/Await Pattern

Note: The async functions (async, await, all, race, map, batch, retry) are provided by the jerome/matrix library, which is included as a dependency.

Using Async/Await

// Import async/await functions from Matrix library
use function async;
use function await;

// Wrap your fetch call in an async function
$promise = async(function() {
    return fetch('https://api.example.com/users');
});

// Await the result
$response = await($promise);
$users = $response->json();

echo "Fetched " . count($users) . " users";

Multiple Concurrent Requests with Async/Await

// These async functions are provided by the Matrix library dependency
use function async;
use function await;
use function all;

// Execute an async function
await(async(function() {
    // Create multiple requests
    $results = await(all([
        'users' => async(fn() => fetch('https://api.example.com/users')),
        'posts' => async(fn() => fetch('https://api.example.com/posts')),
        'comments' => async(fn() => fetch('https://api.example.com/comments'))
    ]));

    // Process the results
    $users = $results['users']->json();
    $posts = $results['posts']->json();
    $comments = $results['comments']->json();

    echo "Fetched " . count($users) . " users, " .
         count($posts) . " posts, and " .
         count($comments) . " comments";
}));

Sequential Requests with Async/Await

use function async;
use function await;

await(async(function() {
    // First request: get auth token
    $authResponse = await(async(fn() =>
        fetch('https://api.example.com/auth/login', [
            'method' => 'POST',
            'json' => [
                'username' => 'user',
                'password' => 'pass'
            ]
        ])
    ));

    $token = $authResponse->json()['token'];

    // Second request: use token to get user data
    $userResponse = await(async(fn() =>
        fetch('https://api.example.com/me', [
            'token' => $token
        ])
    ));

    return $userResponse->json();
}));

Error Handling with Async/Await

use function async;
use function await;

try {
    $data = await(async(function() {
        $response = await(async(fn() =>
            fetch('https://api.example.com/users/999')
        ));

        if ($response->isNotFound()) {
            throw new \Exception("User not found");
        }

        return $response->json();
    }));

    // Process the data

} catch (\Exception $e) {
    echo "Error: " . $e->getMessage();
}

Traditional Promise-based Pattern

// Set up an async request
// Get the handler for async operations
$handler = fetch_client()->getHandler();
$handler->async();

// Make the async request
$promise = $handler->get('https://api.example.com/users');

// Handle the result with callbacks
$promise->then(
    function ($response) {
        // Process successful response
        $users = $response->json();
        foreach ($users as $user) {
            echo $user['name'] . PHP_EOL;
        }
    },
    function ($exception) {
        // Handle errors
        echo "Error: " . $exception->getMessage();
    }
);

Advanced Async Usage

Concurrent Requests with Promise Utilities

use function race;

// Create promises for redundant endpoints
$promises = [
    async(fn() => fetch('https://api1.example.com/data')),
    async(fn() => fetch('https://api2.example.com/data')),
    async(fn() => fetch('https://api3.example.com/data'))
];

// Get the result from whichever completes first
$response = await(race($promises));
$data = $response->json();
echo "Got data from the fastest source";

Controlled Concurrency with Map

use function map;

// List of user IDs to fetch
$userIds = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];

// Process at most 3 requests at a time
$responses = await(map($userIds, function($id) {
    return async(function() use ($id) {
        return fetch("https://api.example.com/users/{$id}");
    });
}, 3));

// Process the responses
foreach ($responses as $index => $response) {
    $user = $response->json();
    echo "Processed user {$user['name']}\n";
}

Batch Processing

use function batch;

// Array of items to process
$items = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];

// Process in batches of 3 with max 2 concurrent batches
$results = await(batch(
    $items,
    function($batch) {
        // Process a batch
        return async(function() use ($batch) {
            $batchResults = [];
            foreach ($batch as $id) {
                $response = await(async(fn() =>
                    fetch("https://api.example.com/users/{$id}")
                ));
                $batchResults[] = $response->json();
            }
            return $batchResults;
        });
    },
    3, // batch size
    2  // concurrency
));

With Retries

use function retry;

// Retry a flaky request up to 3 times with exponential backoff
$data = await(retry(
    function() {
        return async(function() {
            return fetch('https://api.example.com/unstable-endpoint');
        });
    },
    3, // max attempts
    function($attempt) {
        // Exponential backoff strategy
        return min(pow(2, $attempt) * 100, 1000);
    }
));

Advanced Configuration

Automatic Retries

Fetch PHP automatically retries transient failures with exponential backoff.

• Default: No retries enabled (set maxRetries to null by default)
• Default delay: 100ms base with exponential backoff (when retries configured)
• Retry triggers:
  • Network/connect errors (e.g., ConnectException)
  • HTTP status codes: 408, 429, 500, 502, 503, 504, 507, 509, 520-523, 525, 527, 530 (customizable)

Configure per-request:

$response = fetch_client()
    ->retry(3, 200)                // 3 retries, 200ms base delay
    ->retryStatusCodes([429, 503]) // optional: customize which statuses retry
    ->retryExceptions([ConnectException::class]) // optional: customize exception types
    ->get('https://api.example.com/unstable');

Notes:

• HTTP error statuses do not throw; you receive the response. Retries happen internally when configured.
• Network failures are retried and, if all attempts fail, throw a Fetch\Exceptions\RequestException.

Authentication

// Basic auth
$response = fetch('https://api.example.com/secure', [
    'auth' => ['username', 'password']
]);

// Bearer token
$response = fetch_client()
    ->withToken('your-oauth-token')
    ->get('https://api.example.com/secure');

Proxies

$response = fetch('https://api.example.com', [
    'proxy' => 'http://proxy.example.com:8080'
]);

// Or with fluent API
$response = fetch_client()
    ->withProxy('http://proxy.example.com:8080')
    ->get('https://api.example.com');

Global Client Configuration

// Configure once at application bootstrap
fetch_client([
    'base_uri' => 'https://api.example.com',
    'headers' => [
        'User-Agent' => 'MyApp/1.0',
        'Accept' => 'application/json',
    ],
    'timeout' => 10,
]);

// Use the configured client throughout your application
function getUserData($userId) {
    return fetch_client()->get("/users/{$userId}")->json();
}

function createUser($userData) {
    return fetch_client()->post('/users', $userData)->json();
}

Working with Responses

$response = fetch('https://api.example.com/users/1');

// Check if request was successful
if ($response->successful()) {
    // HTTP status code
    echo $response->getStatusCode(); // 200

    // Response body as JSON (returns array by default)
    $user = $response->json();

    // Response body as object
    $userObject = $response->object();

    // Response body as array
    $userArray = $response->array();

    // Response body as string
    $body = $response->text();

    // Get a specific header
    $contentType = $response->getHeaderLine('Content-Type');

    // Check status code categories
    if ($response->isSuccess()) {
        echo "Request succeeded (2xx)";
    }

    if ($response->isOk()) {
        echo "Request returned 200 OK";
    }

    if ($response->isNotFound()) {
        echo "Resource not found (404)";
    }
}

// ArrayAccess support
$name = $response['name']; // Access JSON response data directly

// Inspect retry-related statuses explicitly if needed
if ($response->getStatusCode() === 429) {
    // Handle rate limit response
}

## Working with Type-Safe Enums

```php
use Fetch\Enum\Method;
use Fetch\Enum\ContentType;
use Fetch\Enum\Status;

// Use enums for HTTP methods
$client = fetch_client();
$response = $client->request(Method::POST, '/users', $userData);

// Check HTTP status with enums
if ($response->statusEnum() === Status::OK) {
    // Process successful response
}

// Or use the isStatus helper
if ($response->isStatus(Status::OK)) {
    // Process successful response
}

// Content type handling
$response = $client->withBody($data, ContentType::JSON)->post('/users');

Error Handling

// Synchronous error handling
try {
    $response = fetch('https://api.example.com/nonexistent');

    if (!$response->successful()) {
        echo "Request failed with status: " . $response->getStatusCode();
    }
} catch (\Throwable $e) {
    echo "Exception: " . $e->getMessage();
}

// Asynchronous error handling
$handler = fetch_client()->getHandler();
$handler->async();

$promise = $handler->get('https://api.example.com/nonexistent')
    ->then(function ($response) {
        if ($response->successful()) {
            return $response->json();
        }
        throw new \Exception("Request failed with status: " . $response->getStatusCode());
    })
    ->catch(function (\Throwable $e) {
        echo "Error: " . $e->getMessage();
    });

Timeouts

Control both total request timeout and connection timeout:

$response = fetch('https://api.example.com/data', [
    'timeout' => 15,          // total request timeout (seconds)
    'connect_timeout' => 5,   // connection timeout (seconds)
]);

If connect_timeout is not provided, it defaults to the timeout value.

Logging and Redaction

When request/response logging is enabled via a logger, sensitive values are redacted:

• Headers: Authorization, X-API-Key, API-Key, X-Auth-Token, Cookie, Set-Cookie
• Options: auth credentials

Logged context includes method, URI, selected options (sanitized), status code, duration, and content length.

Caching (sync-only)

Note: Caching is available for synchronous requests only. Async requests intentionally bypass the cache.

Fetch PHP implements RFC 7234-aware HTTP caching with ETag/Last-Modified revalidation, stale-while-revalidate, and stale-if-error support. The default backend is an in-memory cache (MemoryCache), but you can use FileCache or implement your own backend via CacheInterface.

Cache Behavior

• Cacheable methods by default: GET, HEAD
• Cacheable status codes: 200, 203, 204, 206, 300, 301, 404, 410 (RFC 7234 defaults)
• Cache-Control headers respected: no-store, no-cache, max-age, s-maxage, etc.
• Revalidation: Automatically adds If-None-Match (ETag) and If-Modified-Since (Last-Modified) headers for stale entries
• 304 Not Modified: Merges headers and returns cached body
• Vary headers: Supports cache variance by headers (default: Accept, Accept-Encoding, Accept-Language)

Basic Cache Setup

use Fetch\Cache\MemoryCache;
use Fetch\Cache\FileCache;

$handler = fetch_client()->getHandler();

// Enable cache with in-memory backend (default)
$handler->withCache();

// Or use file-based cache
$handler->withCache(new FileCache('/path/to/cache'));

// Disable cache
$handler->withoutCache();

$response = $handler->get('https://api.example.com/users');

Advanced Cache Configuration

$handler->withCache(null, [
    'ttl' => 3600,                      // Default TTL in seconds (overridden by Cache-Control)
    'respect_headers' => true,           // Respect Cache-Control headers (default: true)
    'is_shared_cache' => false,          // Act as shared cache (respects s-maxage)
    'stale_while_revalidate' => 60,      // Serve stale for 60s while revalidating
    'stale_if_error' => 300,             // Serve stale for 300s if backend fails
    'vary_headers' => ['Accept', 'Accept-Language'], // Headers to vary cache by
    'cache_methods' => ['GET', 'HEAD'],  // Cacheable HTTP methods
    'cache_status_codes' => [200, 301],  // Cacheable status codes
    'force_refresh' => false,            // Bypass cache and force fresh request
]);

Per-Request Cache Control

// Force a fresh request (bypass cache)
$response = $handler->withOptions(['cache' => ['force_refresh' => true]])
    ->get('https://api.example.com/users');

// Custom TTL for specific request
$response = $handler->withOptions(['cache' => ['ttl' => 600]])
    ->get('https://api.example.com/users');

// Custom cache key
$response = $handler->withOptions(['cache' => ['key' => 'custom:users']])
    ->get('https://api.example.com/users');

Connection Pooling & HTTP/2

Connection pooling enables reuse of TCP connections across multiple requests, reducing latency and improving performance. The pool is shared globally across all handler instances, and includes DNS caching for faster lookups.

Enable Connection Pooling

$handler = fetch_client()->getHandler();

// Enable with default settings
$handler->withConnectionPool(true);

// Or configure with custom options
$handler->withConnectionPool([
    'enabled' => true,
    'max_connections' => 50,        // Total connections across all hosts
    'max_per_host' => 10,           // Max connections per host
    'connection_ttl' => 60,         // Connection lifetime in seconds
    'idle_timeout' => 30,           // Idle connection timeout in seconds
    'dns_cache_ttl' => 300,         // DNS cache TTL in seconds
]);

Enable HTTP/2

// Enable HTTP/2 (requires curl with HTTP/2 support)
$handler->withHttp2(true);

// Or configure with options
$handler->withHttp2([
    'enabled' => true,
    // Additional HTTP/2 configuration options...
]);

Pool Management

// Get pool statistics
$stats = $handler->getPoolStats();
// Returns: connections_created, connections_reused, total_requests, total_latency_ms

// Close all active connections
$handler->closeAllConnections();

// Reset pool and DNS cache (useful for testing)
$handler->resetPool();

Note: The connection pool is static/global and shared across all handlers. Call resetPool() in your test teardown to ensure isolation between tests.

Debugging & Profiling

Enable debug snapshots and optional profiling:

$handler = fetch_client()->getHandler();

// Enable debug with default options (captures everything)
$handler->withDebug();

// Or enable with specific options
$handler->withDebug([
    'request_headers' => true,
    'request_body' => true,
    'response_headers' => true,
    'response_body' => 1024,  // Truncate response body at 1024 bytes
    'timing' => true,
    'memory' => true,
    'dns_resolution' => true,
]);

// Enable profiling
$handler->withProfiler(new \Fetch\Support\FetchProfiler);

// Set log level (requires PSR-3 logger to be configured)
$handler->withLogLevel('info'); // default: debug

$response = $handler->get('https://api.example.com/users');

// Get debug info from last request
$debug = $handler->getLastDebugInfo();

Testing Support

Fetch PHP includes built-in testing utilities for mocking HTTP responses:

use Fetch\Testing\MockResponse;
use Fetch\Testing\MockResponseSequence;

// Mock a single response
$handler = fetch_client()->getHandler();
$handler->mock(MockResponse::make(['id' => 1, 'name' => 'John'], 200));

$response = $handler->get('https://api.example.com/users/1');
// Returns mocked response without making actual HTTP request

// Mock a sequence of responses
$sequence = new MockResponseSequence([
    MockResponse::make(['id' => 1], 200),
    MockResponse::make(['id' => 2], 200),
    MockResponse::make(null, 404),
]);

$handler->mock($sequence);
// Each subsequent request returns the next response in sequence

Advanced Response Features

Response Status Checks

$response = fetch('https://api.example.com/data');

// Status category checks
$response->isInformational(); // 1xx
$response->isSuccess();       // 2xx
$response->isRedirection();   // 3xx
$response->isClientError();   // 4xx
$response->isServerError();   // 5xx

// Specific status checks
$response->isOk();            // 200
$response->isCreated();       // 201
$response->isNoContent();     // 204
$response->isNotFound();      // 404
$response->isForbidden();     // 403
$response->isUnauthorized();  // 401

// Generic status check
$response->isStatus(Status::CREATED);
$response->isStatus(201);

Response Helpers

// Check if response contains JSON
if ($response->isJson()) {
    $data = $response->json();
}

// Get response as different types with error handling
$data = $response->json(assoc: true, throwOnError: false);
$object = $response->object(throwOnError: false);
$array = $response->array(throwOnError: false);

Connection Pool Management

Clean up connections or reset the pool (useful in tests):

$handler = fetch_client()->getHandler();

// Close all active connections
$handler->closeAllConnections();

// Reset the entire pool and DNS cache (useful in tests)
$handler->resetPool();

// Get pool statistics
$stats = $handler->getPoolStats();
// Returns: connections_created, connections_reused, total_requests, total_latency_ms

Async Notes

• Async requests use the same pipeline (mocking, profiling, logging) but bypass caching by design.
• Matrix helpers (async, await, all, race, map, batch, retry) are re-exported in Fetch\Support\helpers.php.
• Errors are wrapped with method/URL context while preserving the original exception chain.
• Use $handler->async() to enable async mode, or use the Matrix async utilities directly.

License

This project is licensed under the MIT License – see the LICENSE file for full terms.

The MIT License allows you to:

• Use the software for any purpose, including commercial applications
• Modify and distribute the software
• Include it in proprietary software
• Use it without warranty or liability concerns

This permissive license encourages adoption while maintaining attribution requirements.

Contributing

Contributions are welcome! We're currently looking for help with:

• Expanding test coverage
• Improving documentation
• Adding support for additional HTTP features

To contribute:

1. Fork the Project
2. Create your Feature Branch (git checkout -b feature/amazing-feature)
3. Commit your Changes (git commit -m 'Add some amazing-feature')
4. Push to the Branch (git push origin feature/amazing-feature)
5. Open a Pull Request

Acknowledgments

• Thanks to Guzzle HTTP for providing the underlying HTTP client
• Thanks to all contributors who have helped improve this package
• Special thanks to the PHP community for their support and feedback