index.js•9.95 kB
"use strict";
var __importDefault = (this && this.__importDefault) || function (mod) {
return (mod && mod.__esModule) ? mod : { "default": mod };
};
Object.defineProperty(exports, "__esModule", { value: true });
exports.Server = void 0;
const protocol_js_1 = require("../shared/protocol.js");
const types_js_1 = require("../types.js");
const ajv_1 = __importDefault(require("ajv"));
/**
* An MCP server on top of a pluggable transport.
*
* This server will automatically respond to the initialization flow as initiated from the client.
*
* To use with custom types, extend the base Request/Notification/Result types and pass them as type parameters:
*
* ```typescript
* // Custom schemas
* const CustomRequestSchema = RequestSchema.extend({...})
* const CustomNotificationSchema = NotificationSchema.extend({...})
* const CustomResultSchema = ResultSchema.extend({...})
*
* // Type aliases
* type CustomRequest = z.infer<typeof CustomRequestSchema>
* type CustomNotification = z.infer<typeof CustomNotificationSchema>
* type CustomResult = z.infer<typeof CustomResultSchema>
*
* // Create typed server
* const server = new Server<CustomRequest, CustomNotification, CustomResult>({
* name: "CustomServer",
* version: "1.0.0"
* })
* ```
*/
class Server extends protocol_js_1.Protocol {
/**
* Initializes this server with the given name and version information.
*/
constructor(_serverInfo, options) {
var _a;
super(options);
this._serverInfo = _serverInfo;
this._capabilities = (_a = options === null || options === void 0 ? void 0 : options.capabilities) !== null && _a !== void 0 ? _a : {};
this._instructions = options === null || options === void 0 ? void 0 : options.instructions;
this.setRequestHandler(types_js_1.InitializeRequestSchema, (request) => this._oninitialize(request));
this.setNotificationHandler(types_js_1.InitializedNotificationSchema, () => { var _a; return (_a = this.oninitialized) === null || _a === void 0 ? void 0 : _a.call(this); });
}
/**
* Registers new capabilities. This can only be called before connecting to a transport.
*
* The new capabilities will be merged with any existing capabilities previously given (e.g., at initialization).
*/
registerCapabilities(capabilities) {
if (this.transport) {
throw new Error("Cannot register capabilities after connecting to transport");
}
this._capabilities = (0, protocol_js_1.mergeCapabilities)(this._capabilities, capabilities);
}
assertCapabilityForMethod(method) {
var _a, _b, _c;
switch (method) {
case "sampling/createMessage":
if (!((_a = this._clientCapabilities) === null || _a === void 0 ? void 0 : _a.sampling)) {
throw new Error(`Client does not support sampling (required for ${method})`);
}
break;
case "elicitation/create":
if (!((_b = this._clientCapabilities) === null || _b === void 0 ? void 0 : _b.elicitation)) {
throw new Error(`Client does not support elicitation (required for ${method})`);
}
break;
case "roots/list":
if (!((_c = this._clientCapabilities) === null || _c === void 0 ? void 0 : _c.roots)) {
throw new Error(`Client does not support listing roots (required for ${method})`);
}
break;
case "ping":
// No specific capability required for ping
break;
}
}
assertNotificationCapability(method) {
switch (method) {
case "notifications/message":
if (!this._capabilities.logging) {
throw new Error(`Server does not support logging (required for ${method})`);
}
break;
case "notifications/resources/updated":
case "notifications/resources/list_changed":
if (!this._capabilities.resources) {
throw new Error(`Server does not support notifying about resources (required for ${method})`);
}
break;
case "notifications/tools/list_changed":
if (!this._capabilities.tools) {
throw new Error(`Server does not support notifying of tool list changes (required for ${method})`);
}
break;
case "notifications/prompts/list_changed":
if (!this._capabilities.prompts) {
throw new Error(`Server does not support notifying of prompt list changes (required for ${method})`);
}
break;
case "notifications/cancelled":
// Cancellation notifications are always allowed
break;
case "notifications/progress":
// Progress notifications are always allowed
break;
}
}
assertRequestHandlerCapability(method) {
switch (method) {
case "sampling/createMessage":
if (!this._capabilities.sampling) {
throw new Error(`Server does not support sampling (required for ${method})`);
}
break;
case "logging/setLevel":
if (!this._capabilities.logging) {
throw new Error(`Server does not support logging (required for ${method})`);
}
break;
case "prompts/get":
case "prompts/list":
if (!this._capabilities.prompts) {
throw new Error(`Server does not support prompts (required for ${method})`);
}
break;
case "resources/list":
case "resources/templates/list":
case "resources/read":
if (!this._capabilities.resources) {
throw new Error(`Server does not support resources (required for ${method})`);
}
break;
case "tools/call":
case "tools/list":
if (!this._capabilities.tools) {
throw new Error(`Server does not support tools (required for ${method})`);
}
break;
case "ping":
case "initialize":
// No specific capability required for these methods
break;
}
}
async _oninitialize(request) {
const requestedVersion = request.params.protocolVersion;
this._clientCapabilities = request.params.capabilities;
this._clientVersion = request.params.clientInfo;
const protocolVersion = types_js_1.SUPPORTED_PROTOCOL_VERSIONS.includes(requestedVersion)
? requestedVersion
: types_js_1.LATEST_PROTOCOL_VERSION;
return {
protocolVersion,
capabilities: this.getCapabilities(),
serverInfo: this._serverInfo,
...(this._instructions && { instructions: this._instructions }),
};
}
/**
* After initialization has completed, this will be populated with the client's reported capabilities.
*/
getClientCapabilities() {
return this._clientCapabilities;
}
/**
* After initialization has completed, this will be populated with information about the client's name and version.
*/
getClientVersion() {
return this._clientVersion;
}
getCapabilities() {
return this._capabilities;
}
async ping() {
return this.request({ method: "ping" }, types_js_1.EmptyResultSchema);
}
async createMessage(params, options) {
return this.request({ method: "sampling/createMessage", params }, types_js_1.CreateMessageResultSchema, options);
}
async elicitInput(params, options) {
const result = await this.request({ method: "elicitation/create", params }, types_js_1.ElicitResultSchema, options);
// Validate the response content against the requested schema if action is "accept"
if (result.action === "accept" && result.content) {
try {
const ajv = new ajv_1.default();
const validate = ajv.compile(params.requestedSchema);
const isValid = validate(result.content);
if (!isValid) {
throw new types_js_1.McpError(types_js_1.ErrorCode.InvalidParams, `Elicitation response content does not match requested schema: ${ajv.errorsText(validate.errors)}`);
}
}
catch (error) {
if (error instanceof types_js_1.McpError) {
throw error;
}
throw new types_js_1.McpError(types_js_1.ErrorCode.InternalError, `Error validating elicitation response: ${error}`);
}
}
return result;
}
async listRoots(params, options) {
return this.request({ method: "roots/list", params }, types_js_1.ListRootsResultSchema, options);
}
async sendLoggingMessage(params) {
return this.notification({ method: "notifications/message", params });
}
async sendResourceUpdated(params) {
return this.notification({
method: "notifications/resources/updated",
params,
});
}
async sendResourceListChanged() {
return this.notification({
method: "notifications/resources/list_changed",
});
}
async sendToolListChanged() {
return this.notification({ method: "notifications/tools/list_changed" });
}
async sendPromptListChanged() {
return this.notification({ method: "notifications/prompts/list_changed" });
}
}
exports.Server = Server;
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