PromptTuner MCP

import type { RetryOptions } from '../config/types.js'; import { ErrorCode, logger, McpError } from './errors.js'; const DEFAULT_OPTIONS: Required<RetryOptions> = { maxRetries: parseInt(process.env.RETRY_MAX_ATTEMPTS ?? '3', 10), baseDelayMs: parseInt(process.env.RETRY_BASE_DELAY_MS ?? '1000', 10), maxDelayMs: parseInt(process.env.RETRY_MAX_DELAY_MS ?? '10000', 10), totalTimeoutMs: parseInt(process.env.RETRY_TOTAL_TIMEOUT_MS ?? '180000', 10), }; const RETRYABLE_ERROR_CODES = new Set([ 'ECONNRESET', 'ETIMEDOUT', 'ENOTFOUND', 'EAI_AGAIN', 'ECONNREFUSED', 'rate_limit_exceeded', 'overloaded', 'service_unavailable', ]); const RETRYABLE_HTTP_CODES = new Set(['429', '500', '502', '503', '504']); const NON_RETRYABLE_MCP_CODES = new Set<string>([ ErrorCode.E_LLM_AUTH_FAILED, ErrorCode.E_INVALID_INPUT, ]); const RETRYABLE_MCP_CODES = new Set<string>([ ErrorCode.E_LLM_RATE_LIMITED, ErrorCode.E_TIMEOUT, ]); function isRetryableError(error: unknown): boolean { if (error instanceof McpError) { if (NON_RETRYABLE_MCP_CODES.has(error.code)) return false; if (RETRYABLE_MCP_CODES.has(error.code)) return true; } if (error instanceof Error && 'code' in error) { const code = String(error.code); if (RETRYABLE_ERROR_CODES.has(code)) return true; } const errorMessage = error instanceof Error ? error.message.toLowerCase() : String(error).toLowerCase(); for (const code of RETRYABLE_ERROR_CODES) { if (errorMessage.includes(code.toLowerCase())) return true; } for (const httpCode of RETRYABLE_HTTP_CODES) { if (errorMessage.includes(httpCode)) return true; } return false; } function calculateDelay( attempt: number, baseDelayMs: number, maxDelayMs: number ): number { const exponentialDelay = baseDelayMs * Math.pow(2, attempt); const jitter = Math.random() * 0.3 * exponentialDelay; return Math.min(exponentialDelay + jitter, maxDelayMs); } function sleep(ms: number): Promise<void> { return new Promise((resolve) => setTimeout(resolve, ms)); } export async function withRetry<T>( handler: () => Promise<T>, options: RetryOptions = {} ): Promise<T> { const opts = { ...DEFAULT_OPTIONS, ...options }; const startTime = Date.now(); let lastError: unknown; for (let attempt = 0; attempt <= opts.maxRetries; attempt++) { if (Date.now() - startTime > opts.totalTimeoutMs) { throw new McpError( ErrorCode.E_TIMEOUT, `Total retry timeout exceeded (${opts.totalTimeoutMs}ms)` ); } try { return await handler(); } catch (error) { lastError = error; if (attempt >= opts.maxRetries) { break; } if (!isRetryableError(error)) { logger.debug( `Non-retryable error: ${error instanceof Error ? error.message : String(error)}` ); break; } const delayMs = calculateDelay( attempt, opts.baseDelayMs, opts.maxDelayMs ); if (Date.now() - startTime + delayMs > opts.totalTimeoutMs) { logger.warn('Retry loop would exceed total timeout, aborting'); break; } logger.warn( `Retry ${attempt + 1}/${opts.maxRetries + 1} in ${Math.round(delayMs)}ms: ${error instanceof Error ? error.message : String(error)}` ); await sleep(delayMs); if (Date.now() - startTime > opts.totalTimeoutMs) { throw new McpError( ErrorCode.E_TIMEOUT, `Total retry timeout exceeded (${opts.totalTimeoutMs}ms)` ); } } } throw lastError; }