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Fix: implement proper MCP protocol version negotiation #35

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Merged
merged 3 commits into from
Jun 26, 2025
Merged

Fix: implement proper MCP protocol version negotiation #35

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31a7bb2
fix: implement proper MCP protocol version negotiation
CodeWithKyrian Jun 26, 2025
4903299
fix: store negotiated protocol version in session
CodeWithKyrian Jun 26, 2025
6be1d60
fix(tests): update expectations for session in initialize
CodeWithKyrian Jun 26, 2025
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14 changes: 6 additions & 8 deletions src/Dispatcher.php
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Original file line number Diff line number Diff line change
Expand Up @@ -119,16 +119,14 @@ public function handleNotification(Notification $notification, SessionInterface

public function handleInitialize(InitializeRequest $request, SessionInterface $session): InitializeResult
{
if (! in_array($request->protocolVersion, Protocol::SUPPORTED_PROTOCOL_VERSIONS)) {
$this->logger->warning("Unsupported protocol version: {$request->protocolVersion}", [
'supportedVersions' => Protocol::SUPPORTED_PROTOCOL_VERSIONS,
]);
if (in_array($request->protocolVersion, Protocol::SUPPORTED_PROTOCOL_VERSIONS)) {
$protocolVersion = $request->protocolVersion;
} else {
$protocolVersion = Protocol::LATEST_PROTOCOL_VERSION;
}

$protocolVersion = Protocol::LATEST_PROTOCOL_VERSION;

$session->set('client_info', $request->clientInfo);

$session->set('client_info', $request->clientInfo->toArray());
$session->set('protocol_version', $protocolVersion);

$serverInfo = $this->configuration->serverInfo;
$capabilities = $this->configuration->capabilities;
Expand Down
44 changes: 36 additions & 8 deletions tests/Unit/DispatcherTest.php
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Original file line number Diff line number Diff line change
Expand Up @@ -100,7 +100,8 @@
'capabilities' => [],
]
);
$this->session->shouldReceive('set')->with('client_info', Mockery::on(fn ($value) => $value->name === 'client' && $value->version === '1.0'))->once();
$this->session->shouldReceive('set')->with('client_info', Mockery::on(fn($value) => $value['name'] === 'client' && $value['version'] === '1.0'))->once();
$this->session->shouldReceive('set')->with('protocol_version', Protocol::LATEST_PROTOCOL_VERSION)->once();

$result = $this->dispatcher->handleRequest($request, $this->session);
expect($result)->toBeInstanceOf(InitializeResult::class);
Expand Down Expand Up @@ -135,7 +136,34 @@
it('can handle initialize request', function () {
$clientInfo = Implementation::make('TestClient', '0.9.9');
$request = InitializeRequest::make(1, Protocol::LATEST_PROTOCOL_VERSION, ClientCapabilities::make(), $clientInfo, []);
$this->session->shouldReceive('set')->with('client_info', $clientInfo)->once();
$this->session->shouldReceive('set')->with('client_info', $clientInfo->toArray())->once();
$this->session->shouldReceive('set')->with('protocol_version', Protocol::LATEST_PROTOCOL_VERSION)->once();

$result = $this->dispatcher->handleInitialize($request, $this->session);
expect($result->protocolVersion)->toBe(Protocol::LATEST_PROTOCOL_VERSION);
expect($result->serverInfo->name)->toBe('DispatcherTestServer');
expect($result->capabilities)->toBeInstanceOf(ServerCapabilities::class);
});

it('can handle initialize request with older supported protocol version', function () {
$clientInfo = Implementation::make('TestClient', '0.9.9');
$clientRequestedVersion = '2024-11-05';
$request = InitializeRequest::make(1, $clientRequestedVersion, ClientCapabilities::make(), $clientInfo, []);
$this->session->shouldReceive('set')->with('client_info', $clientInfo->toArray())->once();
$this->session->shouldReceive('set')->with('protocol_version', $clientRequestedVersion)->once();

$result = $this->dispatcher->handleInitialize($request, $this->session);
expect($result->protocolVersion)->toBe($clientRequestedVersion);
expect($result->serverInfo->name)->toBe('DispatcherTestServer');
expect($result->capabilities)->toBeInstanceOf(ServerCapabilities::class);
});

it('can handle initialize request with unsupported protocol version', function () {
$clientInfo = Implementation::make('TestClient', '0.9.9');
$unsupportedVersion = '1999-01-01';
$request = InitializeRequest::make(1, $unsupportedVersion, ClientCapabilities::make(), $clientInfo, []);
$this->session->shouldReceive('set')->with('client_info', $clientInfo->toArray())->once();
$this->session->shouldReceive('set')->with('protocol_version', Protocol::LATEST_PROTOCOL_VERSION)->once();

$result = $this->dispatcher->handleInitialize($request, $this->session);
expect($result->protocolVersion)->toBe(Protocol::LATEST_PROTOCOL_VERSION);
Expand Down Expand Up @@ -256,14 +284,14 @@
$requestP1 = ListResourcesRequest::make(1);
$resultP1 = $this->dispatcher->handleResourcesList($requestP1);
expect($resultP1->resources)->toHaveCount(DISPATCHER_PAGINATION_LIMIT);
expect(array_map(fn ($r) => $r->name, $resultP1->resources))->toEqual(['Resource1', 'Resource2', 'Resource3']);
expect(array_map(fn($r) => $r->name, $resultP1->resources))->toEqual(['Resource1', 'Resource2', 'Resource3']);
expect($resultP1->nextCursor)->toBe(base64_encode('offset=3'));

// Page 2
$requestP2 = ListResourcesRequest::make(2, $resultP1->nextCursor);
$resultP2 = $this->dispatcher->handleResourcesList($requestP2);
expect($resultP2->resources)->toHaveCount(2);
expect(array_map(fn ($r) => $r->name, $resultP2->resources))->toEqual(['Resource4', 'Resource5']);
expect(array_map(fn($r) => $r->name, $resultP2->resources))->toEqual(['Resource4', 'Resource5']);
expect($resultP2->nextCursor)->toBeNull();
});

Expand All @@ -288,14 +316,14 @@
$requestP1 = ListResourceTemplatesRequest::make(1);
$resultP1 = $this->dispatcher->handleResourceTemplateList($requestP1);
expect($resultP1->resourceTemplates)->toHaveCount(DISPATCHER_PAGINATION_LIMIT);
expect(array_map(fn ($rt) => $rt->name, $resultP1->resourceTemplates))->toEqual(['Template1', 'Template2', 'Template3']);
expect(array_map(fn($rt) => $rt->name, $resultP1->resourceTemplates))->toEqual(['Template1', 'Template2', 'Template3']);
expect($resultP1->nextCursor)->toBe(base64_encode('offset=3'));

// Page 2
$requestP2 = ListResourceTemplatesRequest::make(2, $resultP1->nextCursor);
$resultP2 = $this->dispatcher->handleResourceTemplateList($requestP2);
expect($resultP2->resourceTemplates)->toHaveCount(1);
expect(array_map(fn ($rt) => $rt->name, $resultP2->resourceTemplates))->toEqual(['Template4']);
expect(array_map(fn($rt) => $rt->name, $resultP2->resourceTemplates))->toEqual(['Template4']);
expect($resultP2->nextCursor)->toBeNull();
});

Expand Down Expand Up @@ -345,14 +373,14 @@
$requestP1 = ListPromptsRequest::make(1);
$resultP1 = $this->dispatcher->handlePromptsList($requestP1);
expect($resultP1->prompts)->toHaveCount(DISPATCHER_PAGINATION_LIMIT);
expect(array_map(fn ($p) => $p->name, $resultP1->prompts))->toEqual(['promptA', 'promptB', 'promptC']);
expect(array_map(fn($p) => $p->name, $resultP1->prompts))->toEqual(['promptA', 'promptB', 'promptC']);
expect($resultP1->nextCursor)->toBe(base64_encode('offset=3'));

// Page 2
$requestP2 = ListPromptsRequest::make(2, $resultP1->nextCursor);
$resultP2 = $this->dispatcher->handlePromptsList($requestP2);
expect($resultP2->prompts)->toHaveCount(DISPATCHER_PAGINATION_LIMIT); // 3 more
expect(array_map(fn ($p) => $p->name, $resultP2->prompts))->toEqual(['promptD', 'promptE', 'promptF']);
expect(array_map(fn($p) => $p->name, $resultP2->prompts))->toEqual(['promptD', 'promptE', 'promptF']);
expect($resultP2->nextCursor)->toBeNull(); // End of list
});

Expand Down