Fonoster MCP Server

/** * Copyright (C) 2025 by Fonoster Inc (https://fonoster.com) * http://github.com/fonoster/fonoster * * This file is part of Fonoster * * Licensed under the MIT License (the "License"); * you may not use this file except in compliance with * the License. You may obtain a copy of the License at * * https://opensource.org/licenses/MIT * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ import { Stream } from "stream"; import { GrpcError, StreamEvent, VoiceClientConfig, VoiceIn, VoiceSessionStreamClient } from "@fonoster/common"; import { getLogger } from "@fonoster/logger"; import * as grpc from "@grpc/grpc-js"; import { GRPCClient } from "../types"; import { VoiceServiceClientConstructor } from "../utils/VoiceServiceClientConstructor"; const logger = getLogger({ service: "apiserver", filePath: __filename }); class GrpcClientHandler { private config: VoiceClientConfig; private verbsStream: Stream; private grpcClient: GRPCClient; private voice: VoiceSessionStreamClient; constructor(params: { config: VoiceClientConfig; verbsStream: Stream }) { this.config = params.config; this.verbsStream = params.verbsStream; } async setupGrpcClient(): Promise<void> { this.grpcClient = new VoiceServiceClientConstructor( this.config.endpoint, grpc.credentials.createInsecure() ) as unknown as GRPCClient; const metadata = new grpc.Metadata(); metadata.add("accessKeyId", this.config.accessKeyId); metadata.add("token", this.config.sessionToken); this.voice = this.grpcClient.createSession(metadata); this.setupEventHandlers(); // Initialize the session this.voice.write({ request: this.config }); } private setupEventHandlers(): void { this.voice.on(StreamEvent.DATA, (data: VoiceIn) => { this.verbsStream.emit(data.content, data); }); this.voice.on(StreamEvent.ERROR, (error: GrpcError) => { if (error.code === grpc.status.UNAVAILABLE) { logger.error(`voice server not available at "${this.config.endpoint}"`); return; } logger.error(`grpc stream error: ${error.message}`); }); } getVoiceStream(): VoiceSessionStreamClient { return this.voice; } sendResponse(response: VoiceIn): void { try { this.voice.write(response); } catch (error) { logger.error(`error sending response: ${error.message}`); } } close(): void { try { this.voice.end(); this.grpcClient.close(); } catch (e) { // Ignore errors on close } } } export { GrpcClientHandler };