import { PackageReadmeMcpError, NetworkError, RateLimitError } from '../types/index.js';
import { logger } from './logger.js';
export class ErrorHandler {
static handleApiError(error: unknown, context: string): never {
logger.error(`API error in ${context}`, { error });
if (error instanceof PackageReadmeMcpError) {
throw error;
}
if (error instanceof Error) {
// Handle fetch errors
if (error.name === 'TypeError' && error.message.includes('fetch')) {
throw new NetworkError(`Failed to fetch data from ${context}`, error);
}
// Handle timeout errors
if (error.message.includes('timeout') || error.message.includes('ETIMEDOUT')) {
throw new NetworkError(`Request timeout for ${context}`, error);
}
// Handle rate limit errors (common HTTP status codes)
if (error.message.includes('429') || error.message.includes('rate limit')) {
throw new RateLimitError(context);
}
// Generic network error
throw new NetworkError(error.message, error);
}
// Unknown error
throw new PackageReadmeMcpError(
`Unknown error in ${context}: ${String(error)}`,
'UNKNOWN_ERROR'
);
}
static async withRetry<T>(
operation: () => Promise<T>,
maxRetries: number = 3,
baseDelay: number = 1000,
context: string = 'operation'
): Promise<T> {
let lastError: unknown;
for (let attempt = 1; attempt <= maxRetries; attempt++) {
try {
return await operation();
} catch (error) {
lastError = error;
// Don't retry on client errors (4xx except 429)
if (error instanceof PackageReadmeMcpError) {
if (error.statusCode && error.statusCode >= 400 && error.statusCode < 500 && error.statusCode !== 429) {
throw error;
}
}
if (attempt === maxRetries) {
logger.error(`All retry attempts failed for ${context}`, {
attempts: maxRetries,
lastError: error
});
break;
}
const delay = baseDelay * Math.pow(2, attempt - 1); // Exponential backoff
logger.warn(`Retry attempt ${attempt}/${maxRetries} for ${context} after ${delay}ms`, {
error: error instanceof Error ? error.message : String(error)
});
await new Promise(resolve => setTimeout(resolve, delay));
}
}
this.handleApiError(lastError, context);
}
static isRetryableError(error: unknown): boolean {
if (error instanceof RateLimitError) {
return true;
}
if (error instanceof NetworkError) {
return true;
}
if (error instanceof PackageReadmeMcpError) {
return error.statusCode === 429 || (error.statusCode !== undefined && error.statusCode >= 500);
}
return false;
}
}
