import { appendFile, mkdir } from "node:fs/promises";
import { join } from "node:path";
import { existsSync } from "node:fs";
import { getGlobalOpensrcDir } from "./config.js";
type LogLevel = "debug" | "info" | "warn" | "error";
interface LogEntry {
timestamp: string;
level: LogLevel;
message: string;
context?: string;
data?: Record<string, unknown>;
error?: {
message: string;
stack?: string;
};
}
const LOG_LEVELS: Record<LogLevel, number> = {
debug: 0,
info: 1,
warn: 2,
error: 3,
};
let logFilePath: string | null = null;
let minLevel: LogLevel = "debug";
/**
* Get the log file path (creates logs dir if needed)
*/
async function getLogFilePath(): Promise<string> {
if (logFilePath) return logFilePath;
const opensrcDir = getGlobalOpensrcDir();
const logsDir = join(opensrcDir, "logs");
if (!existsSync(logsDir)) {
await mkdir(logsDir, { recursive: true });
}
logFilePath = join(logsDir, "opensrc-mcp.log");
return logFilePath;
}
/**
* Set minimum log level
*/
export function setLogLevel(level: LogLevel): void {
minLevel = level;
}
/**
* Get current log file path for tailing
*/
export function getLogPath(): string {
const opensrcDir = getGlobalOpensrcDir();
return join(opensrcDir, "logs", "opensrc-mcp.log");
}
/**
* Write a structured log entry to file
*/
async function writeLog(entry: LogEntry): Promise<void> {
if (LOG_LEVELS[entry.level] < LOG_LEVELS[minLevel]) {
return;
}
try {
const path = await getLogFilePath();
const line = JSON.stringify(entry) + "\n";
await appendFile(path, line, "utf8");
} catch {
// Silently fail - don't break app if logging fails
}
}
/**
* Create a log entry
*/
function createEntry(
level: LogLevel,
message: string,
context?: string,
data?: Record<string, unknown>,
error?: Error
): LogEntry {
const entry: LogEntry = {
timestamp: new Date().toISOString(),
level,
message,
};
if (context) entry.context = context;
if (data) entry.data = data;
if (error) {
entry.error = {
message: error.message,
stack: error.stack,
};
}
return entry;
}
/**
* Logger interface for a specific context
*/
export interface Logger {
debug(message: string, data?: Record<string, unknown>): void;
info(message: string, data?: Record<string, unknown>): void;
warn(message: string, data?: Record<string, unknown>): void;
error(message: string, errorOrData?: Error | Record<string, unknown>): void;
}
/**
* Create a logger for a specific context (e.g., "vector", "server")
*/
export function createLogger(context: string): Logger {
return {
debug(message: string, data?: Record<string, unknown>) {
void writeLog(createEntry("debug", message, context, data));
},
info(message: string, data?: Record<string, unknown>) {
void writeLog(createEntry("info", message, context, data));
},
warn(message: string, data?: Record<string, unknown>) {
void writeLog(createEntry("warn", message, context, data));
},
error(message: string, errorOrData?: Error | Record<string, unknown>) {
const isError = errorOrData instanceof Error;
void writeLog(
createEntry(
"error",
message,
context,
isError ? undefined : errorOrData,
isError ? errorOrData : undefined
)
);
},
};
}
/**
* Root logger (no context)
*/
export const log = createLogger("main");
