OAS Fake PHP

OpenAPI schema-driven fake API server for PHP testing. Define your API contract once, and automatically get a working fake server that generates valid responses, validates requests, and catches schema violations in your tests.

Features

• Automatic fake response generation from OpenAPI schema definitions
• Request/response validation against the OpenAPI schema
• Custom response stubs and callbacks per operation
• Declarative server classes with handler methods mapped by operationId
• Three operating modes: FAKE, RECORD, REPLAY
• PSR-15 middleware support

Requirements

• PHP 8.0+
• ext-curl

Installation

composer require --dev k-kinzal/oas-fake-php

Usage

Basic

Define a server pointing to your OpenAPI schema and start intercepting:

use OasFake\OasFake;
use OasFake\Server;

final class PetStoreServer extends Server
{
    protected static string $SCHEMA = __DIR__ . '/openapi.yaml';
}

// Start intercepting HTTP requests
$server = OasFake::start(PetStoreServer::class);

// All HTTP requests now return responses generated from the schema
$client = new GuzzleHttp\Client(['base_uri' => 'https://petstore.example.com']);
$response = $client->get('/pets/1');

// Stop intercepting
OasFake::stop();

Custom Responses

Override responses for specific operations using the configure callback:

use OasFake\OasFake;
use OasFake\Handler;

$server = OasFake::start(PetStoreServer::class, fn ($s) => $s
    ->withResponse('listPets', 200, [['id' => 1, 'name' => 'Buddy']])
    ->withCallback('createPet', function ($request, $response) {
        $body = json_decode((string) $request->getBody(), true);
        return new \GuzzleHttp\Psr7\Response(201, [], json_encode([
            'id' => 42,
            'name' => $body['name'],
        ]));
    })
    ->withHandler('deletePet', Handler::status(204))
);

Declarative Server

Public methods on a Server subclass are automatically registered as handlers, matched by operationId:

use OasFake\Server;
use GuzzleHttp\Psr7\Response;
use Psr\Http\Message\ResponseInterface;
use Psr\Http\Message\ServerRequestInterface;

final class PetStoreServer extends Server
{
    protected static string $SCHEMA = __DIR__ . '/openapi.yaml';

    public function listPets(ServerRequestInterface $request, ?ResponseInterface $response): ResponseInterface
    {
        return new Response(200, ['Content-Type' => 'application/json'], json_encode([
            ['id' => 1, 'name' => 'Buddy'],
        ]));
    }

    #[\OasFake\Route(method: 'DELETE', path: '/pets/{petId}')]
    public function removePet(ServerRequestInterface $request, ?ResponseInterface $response): ResponseInterface
    {
        return new Response(204);
    }
}

Configuration

use OasFake\OasFake;
use OasFake\Mode;

$server = OasFake::start(PetStoreServer::class, fn ($s) => $s
    ->withMode(Mode::RECORD)  // or ->withMode('record')
    ->withCassettePath('./fixtures/cassettes')
    ->withRequestValidation(false)
    ->withResponseValidation(false)
    ->withFakerOptions(['alwaysFakeOptionals' => true, 'minItems' => 2, 'maxItems' => 5])
    ->withMiddleware(new MyMiddleware())
);

All settings can also be overridden via environment variables:

OAS_FAKE_MODE=record OAS_FAKE_VALIDATE_REQUESTS=false composer test

License

MIT