[Tests] Cover requestState binding and key rotation end to end

tests/Integration/Fixture/request_state.php

@@ -0,0 +1,216 @@
+<?php
+
+/*
+ * This file is part of the official PHP MCP SDK.
+ *
+ * A collaboration between Symfony and the PHP Foundation.
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+/*
+ * Server for the `requestState` tests, over `php -S` or stdio. MCP_REQUEST_STATE_KEYS holds the JSON-encoded key or
+ * key ring, MCP_REQUEST_STATE_BINDER turns on the binder, MCP_REQUEST_STATE_ANONYMOUS drops the authorization,
+ * MCP_REQUEST_STATE_TTL sets the TTL, MCP_REQUEST_STATE_SUBJECT_CLAIM names the claim identifying a user and
+ * MCP_REQUEST_STATE_NO_SHIM turns off the input-required shim, MCP_REQUEST_STATE_SESSIONS keeps sessions in a directory.
+ */
+
+use Http\Discovery\Psr17Factory;
+use Laminas\HttpHandlerRunner\Emitter\SapiEmitter;
+use Mcp\Schema\Content\PromptMessage;
+use Mcp\Schema\Content\TextContent;
+use Mcp\Schema\Elicitation\ElicitationSchema;
+use Mcp\Schema\Elicitation\StringSchemaDefinition;
+use Mcp\Schema\Enum\Role;
+use Mcp\Schema\JsonRpc\Request;
+use Mcp\Schema\JsonRpc\Response;
+use Mcp\Schema\Request\CallToolRequest;
+use Mcp\Schema\Request\ElicitRequest;
+use Mcp\Schema\Result\CallToolResult;
+use Mcp\Schema\Result\InputRequiredResult;
+use Mcp\Server;
+use Mcp\Server\Authorization\AccessToken;
+use Mcp\Server\Handler\Request\RequestHandlerInterface;
+use Mcp\Server\RequestContext;
+use Mcp\Server\Session\FileSessionStore;
+use Mcp\Server\Session\SessionInterface;
+use Mcp\Server\Stateless\InputContext;
+use Mcp\Server\Stateless\OriginatingRequestBinder;
+use Mcp\Server\Stateless\RequestStateCodec;
+use Mcp\Server\Transport\Http\Middleware\AuthorizationMiddleware;
+use Mcp\Server\Transport\Http\Middleware\PassthroughMiddleware;
+use Mcp\Server\Transport\Http\OAuth\AuthorizationResult;
+use Mcp\Server\Transport\Http\OAuth\AuthorizationTokenValidatorInterface;
+use Mcp\Server\Transport\Http\OAuth\ProtectedResourceMetadata;
+use Mcp\Server\Transport\StdioTransport;
+use Mcp\Server\Transport\StreamableHttpTransport;
+
+require_once dirname(__DIR__, 3).'/vendor/autoload.php';
+
+$subject = static fn (RequestContext $context): string => $context->getAccessToken()?->getSubject() ?? 'nobody';
+
+// Two asks, so the second one has to carry the first answer in the state the SDK mints.
+$approver = static function (RequestContext $context): string {
+    $gateway = $context->getClientGateway();
+    $schema = new ElicitationSchema(['v' => new StringSchemaDefinition('Value')], ['v']);
+
+    $approver = $gateway->elicit('Who approves this?', $schema, key: 'approver')->content['v'] ?? '?';
+    $gateway->elicit('One-time code?', $schema, key: 'code');
+
+    return (string) $approver;
+};
+
+$builder = Server::builder()
+    ->setServerInfo('request-state-server', '1.0.0')
+    ->addTool(
+        static fn (RequestContext $context, string $to, int $amount): string => sprintf('%s moved %d to %s, approved by %s', $subject($context), $amount, $to, $approver($context)),
+        name: 'transfer',
+        description: 'Moves money after two asks.',
+    )
+    ->addTool(
+        static fn (RequestContext $context, string $account): string => sprintf('%s closed %s, approved by %s', $subject($context), $account, $approver($context)),
+        name: 'close_account',
+        description: 'Closes an account after the same two asks.',
+    )
+    ->addTool(
+        // Authorizes once and trusts its own signed state on the retry, the reason the state needs integrity at all.
+        static function (RequestContext $context, int $order) use ($subject): CallToolResult|InputRequiredResult {
+            if (true === ($context->getInputContext()?->requestState()['authorized'] ?? null)) {
+                return new CallToolResult([new TextContent(sprintf('%s refunded order %d', $subject($context), $order))]);
+            }
+
+            if (!in_array($subject($context), ['alice', 'nobody'], true)) {
+                return new CallToolResult([new TextContent('Only a manager may refund.')], isError: true);
+            }
+
+            return new InputRequiredResult(
+                ['reason' => new ElicitRequest('Why?', new ElicitationSchema(['v' => new StringSchemaDefinition('Value')], ['v']))],
+                requestState: $context->mintRequestState(['authorized' => true]),
+            );
+        },
+        name: 'refund',
+        description: 'Refunds an order, for managers only.',
+    )
+    ->addTool(
+        // Takes any JSON, so the handler sees the arguments the way the client shaped them.
+        static fn (RequestContext $context, mixed $options): string => sprintf('%s, approved by %s', json_encode($options, depth: 1024), $approver($context)),
+        name: 'inspect',
+        description: 'Echoes what it was given after two asks.',
+    )
+    ->addTool(
+        static function (RequestContext $context, int $amount) use ($approver): string {
+            $context->getClientGateway()->progress(0.5, 1.0);
+
+            return sprintf('reported %d, approved by %s', $amount, $approver($context));
+        },
+        name: 'report',
+        description: 'Reports progress before the two asks, so its rounds answer as a stream.',
+    )
+    ->addRequestHandler(new class implements RequestHandlerInterface {
+        public function supports(Request $request): bool
+        {
+            return $request instanceof CallToolRequest && 'raw' === $request->name;
+        }
+
+        // Skips schema validation, which refuses member names only a handler like this one gets to see.
+        public function handle(Request $request, SessionInterface $session): Response
+        {
+            assert($request instanceof CallToolRequest);
+            $input = $session->get(InputContext::class);
+            $codec = $session->get(RequestStateCodec::class);
+            assert($codec instanceof RequestStateCodec);
+
+            if ($input instanceof InputContext && true === ($input->requestState()['asked'] ?? null)) {
+                return new Response($request->getId(), new CallToolResult([new TextContent((string) json_encode($request->arguments['options'] ?? null))]));
+            }
+
+            $schema = new ElicitationSchema(['v' => new StringSchemaDefinition('Value')], ['v']);
+
+            return new Response($request->getId(), new InputRequiredResult(['v' => new ElicitRequest('Sure?', $schema)], requestState: $codec->mint(['asked' => true])));
+        }
+    })
+    ->addPrompt(
+        static fn (RequestContext $context, string $topic): array => [new PromptMessage(Role::User, new TextContent(sprintf('brief on %s, approved by %s', $topic, $approver($context))))],
+        name: 'brief',
+        description: 'A brief after two asks.',
+    )
+    ->addPrompt(
+        static fn (RequestContext $context, string $topic): array => [new PromptMessage(Role::User, new TextContent(sprintf('leak of %s, approved by %s', $topic, $approver($context))))],
+        name: 'leak',
+        description: 'Another prompt after the same two asks.',
+    )
+    ->addResourceTemplate(
+        static fn (string $id, RequestContext $context): string => sprintf('contents of %s, approved by %s', $id, $approver($context)),
+        'doc://{id}',
+        name: 'doc',
+        mimeType: 'text/plain',
+    )
+    ->addTool(static fn (): string => 'pong', name: 'ping', description: 'Asks nothing.');
+
+$keys = json_decode((string) getenv('MCP_REQUEST_STATE_KEYS'), true, flags: \JSON_THROW_ON_ERROR);
+
+$binder = null;
+
+if ('' !== (string) getenv('MCP_REQUEST_STATE_BINDER')) {
+    $claim = (string) getenv('MCP_REQUEST_STATE_SUBJECT_CLAIM');
+
+    $binder = new OriginatingRequestBinder('' === $claim ? null : static function (AccessToken $token) use ($claim): ?string {
+        $value = $token->getClaim($claim);
+
+        return is_string($value) ? $value : null;
+    });
+}
+
+$builder->setRequestState($keys, (int) (getenv('MCP_REQUEST_STATE_TTL') ?: 600), $binder);
+
+if ('' !== (string) getenv('MCP_REQUEST_STATE_SESSIONS')) {
+    $builder->setSession(new FileSessionStore((string) getenv('MCP_REQUEST_STATE_SESSIONS')));
+}
+
+if ('' !== (string) getenv('MCP_REQUEST_STATE_NO_SHIM')) {
+    $builder->withoutInputRequiredShim();
+}
+
+if ('cli-server' !== \PHP_SAPI) {
+    $builder->build()->run(new StdioTransport());
+
+    return;
+}
+
+$middleware = [new PassthroughMiddleware()];
+
+if ('' === (string) getenv('MCP_REQUEST_STATE_ANONYMOUS')) {
+    $middleware = [new AuthorizationMiddleware(
+        new class implements AuthorizationTokenValidatorInterface {
+            private const ISSUER = 'https://auth.example.com';
+
+            public function validate(string $accessToken): AuthorizationResult
+            {
+                $claims = match ($accessToken) {
+                    'alice' => ['sub' => 'alice', 'client_id' => 'app', 'jti' => 'first'],
+                    'alice-refreshed' => ['sub' => 'alice', 'client_id' => 'app', 'jti' => 'second'],
+                    'alice-other-client' => ['sub' => 'alice', 'client_id' => 'other-app', 'jti' => 'third'],
+                    'alice-other-issuer' => ['sub' => 'alice', 'client_id' => 'app', 'iss' => 'https://other.example.com', 'jti' => 'fifth'],
+                    'mallory' => ['sub' => 'mallory', 'client_id' => 'app', 'jti' => 'fourth'],
+                    'no-subject-alice' => ['client_id' => 'app', 'email' => 'alice@example.com'],
+                    'no-subject-alice-refreshed' => ['client_id' => 'app', 'email' => 'alice@example.com', 'jti' => 'sixth'],
+                    'no-subject-alice-other-client' => ['client_id' => 'other-app', 'email' => 'alice@example.com'],
+                    'no-subject-mallory' => ['client_id' => 'app', 'email' => 'mallory@example.com'],
+                    default => null,
+                };
+
+                if (null === $claims) {
+                    return AuthorizationResult::unauthorized();
+                }
+
+                return AuthorizationResult::allow(new AccessToken(['mcp'], ['iss' => self::ISSUER, ...$claims]));
+            }
+        },
+        new ProtectedResourceMetadata('http://127.0.0.1/', ['http://127.0.0.1/']),
+    )];
+}
+
+$request = (new Psr17Factory())->createServerRequestFromGlobals();
+
+(new SapiEmitter())->emit($builder->build()->run(new StreamableHttpTransport($request, middleware: $middleware)));