import { StreamableHTTPServerTransport } from '@modelcontextprotocol/sdk/server/streamableHttp.js';
/**
* Metadata about a transport's restoration state, used for debugging
* and monitoring session restoration flow.
*/
export interface RestorationInfo {
isRestored: boolean;
sessionId?: string;
}
/**
* RestorableStreamableHTTPServerTransport extends the MCP SDK's StreamableHTTPServerTransport
* to track whether a transport was restored from persistent storage.
*
* This is a minimal wrapper that only adds restoration tracking. Session ID management
* is handled entirely through the SDK's public `sessionIdGenerator` callback - when
* restoring a session, we pass a generator that returns the stored session ID.
*
* @remarks
* The restoration flow works as follows:
* 1. Create transport with `sessionIdGenerator: () => storedSessionId`
* 2. Connect transport to ServerManager
* 3. Call virtualInitialize() which triggers SDK's handleRequest
* 4. SDK calls sessionIdGenerator() internally to get the session ID
* 5. Call markAsRestored() to indicate successful restoration
*
* @example
* ```typescript
* const transport = new RestorableStreamableHTTPServerTransport({
* sessionIdGenerator: () => originalSessionId,
* });
* // After successful virtual initialize...
* transport.markAsRestored();
* // Now transport.isRestored() returns true
* ```
*/
export class RestorableStreamableHTTPServerTransport extends StreamableHTTPServerTransport {
private _isRestored = false;
/**
* Marks this transport as having been restored from persistent storage.
*
* This should be called after successful virtual initialization to indicate
* that the transport is ready to handle requests for a restored session.
*/
markAsRestored(): void {
this._isRestored = true;
}
/**
* Returns whether this transport was created for a restored session.
*
* @returns true if the transport was restored from persistent storage, false otherwise
*/
isRestored(): boolean {
return this._isRestored;
}
/**
* Gets the restoration status for debugging purposes.
*
* @returns Object containing restoration metadata
*/
getRestorationInfo(): RestorationInfo {
return {
isRestored: this._isRestored,
sessionId: this.sessionId,
};
}
}
