import { existsSync } from 'fs';
import { readFile } from 'fs/promises';
import { z } from 'zod';
export const LogEntrySchema = z.object({
level: z.enum(['INFO', 'WARN', 'ERROR', 'DEBUG', 'CRITICAL']),
timestamp: z.string(), // ISO string
message: z.string(),
service_name: z.string().optional(),
user_id: z.string().optional(),
context: z.record(z.any()).optional(),
event: z.record(z.any()).optional(),
});
export type LogEntry = z.infer<typeof LogEntrySchema>;
export async function readAndValidateLogs({
logPath,
lines = 50,
start_time,
end_time,
}: {
logPath: string;
lines?: number;
start_time?: string;
end_time?: string;
}): Promise<LogEntry[]> {
if (!logPath) {
throw new Error('No log file path provided.');
}
if (
logPath.includes('..') ||
/\\/.test(logPath) ||
(!logPath.endsWith('.log') && !logPath.endsWith('.txt'))
) {
throw new Error('Invalid logPath. Only .log and .txt files are allowed.');
}
if (!existsSync(logPath)) {
throw new Error(`File ${logPath} does not exist.`);
}
const content = await readFile(logPath, 'utf-8');
const linesArray = content.split('\n').filter((line) => line.trim());
let validLogs: LogEntry[] = [];
for (const line of linesArray.slice(-lines)) {
try {
const parsed = JSON.parse(line);
const validated = LogEntrySchema.parse(parsed);
validLogs.push(validated);
} catch {
// skip invalid lines
}
}
if (start_time || end_time) {
const start = start_time ? new Date(start_time) : null;
const end = end_time ? new Date(end_time) : new Date();
validLogs = validLogs.filter((log) => {
const ts = new Date(log.timestamp);
if (start && ts < start) return false;
if (end && ts > end) return false;
return true;
});
}
return validLogs;
}
