dcrouter/ts/mail/delivery/smtpclient/error-handler.ts
2025-05-22 10:18:02 +00:00

141 lines
4.0 KiB
TypeScript

/**
* SMTP Client Error Handler
* Error classification and recovery strategies
*/
import { SmtpErrorType } from './constants.js';
import type { ISmtpResponse, ISmtpErrorContext, ISmtpClientOptions } from './interfaces.js';
import { logDebug } from './utils/logging.js';
export class SmtpErrorHandler {
private options: ISmtpClientOptions;
constructor(options: ISmtpClientOptions) {
this.options = options;
}
/**
* Classify error type based on response or error
*/
public classifyError(error: Error | ISmtpResponse, context?: ISmtpErrorContext): SmtpErrorType {
logDebug('Classifying error', this.options, { errorMessage: error instanceof Error ? error.message : String(error), context });
// Handle Error objects
if (error instanceof Error) {
return this.classifyErrorByMessage(error);
}
// Handle SMTP response codes
if (typeof error === 'object' && 'code' in error) {
return this.classifyErrorByCode(error.code);
}
return SmtpErrorType.UNKNOWN_ERROR;
}
/**
* Determine if error is retryable
*/
public isRetryable(errorType: SmtpErrorType, response?: ISmtpResponse): boolean {
switch (errorType) {
case SmtpErrorType.CONNECTION_ERROR:
case SmtpErrorType.TIMEOUT_ERROR:
return true;
case SmtpErrorType.PROTOCOL_ERROR:
// Only retry on temporary failures (4xx codes)
return response ? response.code >= 400 && response.code < 500 : false;
case SmtpErrorType.AUTHENTICATION_ERROR:
case SmtpErrorType.TLS_ERROR:
case SmtpErrorType.SYNTAX_ERROR:
case SmtpErrorType.MAILBOX_ERROR:
case SmtpErrorType.QUOTA_ERROR:
return false;
default:
return false;
}
}
/**
* Get retry delay for error type
*/
public getRetryDelay(attempt: number, errorType: SmtpErrorType): number {
const baseDelay = 1000; // 1 second
const maxDelay = 30000; // 30 seconds
// Exponential backoff with jitter
const delay = Math.min(baseDelay * Math.pow(2, attempt - 1), maxDelay);
const jitter = Math.random() * 0.1 * delay; // 10% jitter
return Math.floor(delay + jitter);
}
/**
* Create enhanced error with context
*/
public createError(
message: string,
errorType: SmtpErrorType,
context?: ISmtpErrorContext,
originalError?: Error
): Error {
const error = new Error(message);
(error as any).type = errorType;
(error as any).context = context;
(error as any).originalError = originalError;
return error;
}
private classifyErrorByMessage(error: Error): SmtpErrorType {
const message = error.message.toLowerCase();
if (message.includes('timeout') || message.includes('etimedout')) {
return SmtpErrorType.TIMEOUT_ERROR;
}
if (message.includes('connect') || message.includes('econnrefused') ||
message.includes('enotfound') || message.includes('enetunreach')) {
return SmtpErrorType.CONNECTION_ERROR;
}
if (message.includes('tls') || message.includes('ssl') ||
message.includes('certificate') || message.includes('handshake')) {
return SmtpErrorType.TLS_ERROR;
}
if (message.includes('auth')) {
return SmtpErrorType.AUTHENTICATION_ERROR;
}
return SmtpErrorType.UNKNOWN_ERROR;
}
private classifyErrorByCode(code: number): SmtpErrorType {
if (code >= 500) {
// Permanent failures
if (code === 550 || code === 551 || code === 553) {
return SmtpErrorType.MAILBOX_ERROR;
}
if (code === 552) {
return SmtpErrorType.QUOTA_ERROR;
}
if (code === 500 || code === 501 || code === 502 || code === 504) {
return SmtpErrorType.SYNTAX_ERROR;
}
return SmtpErrorType.PROTOCOL_ERROR;
}
if (code >= 400) {
// Temporary failures
if (code === 450 || code === 451 || code === 452) {
return SmtpErrorType.QUOTA_ERROR;
}
return SmtpErrorType.PROTOCOL_ERROR;
}
return SmtpErrorType.UNKNOWN_ERROR;
}
}