export enum LogLevel {
DEBUG = 0,
INFO = 1,
WARN = 2,
ERROR = 3,
}
const LOG_LEVEL_NAMES: Record<number, string> = {
[LogLevel.DEBUG]: "DEBUG",
[LogLevel.INFO]: "INFO",
[LogLevel.WARN]: "WARN",
[LogLevel.ERROR]: "ERROR",
};
export class Logger {
private level: LogLevel;
constructor(level?: LogLevel) {
this.level = level ?? this.parseEnvLevel();
}
private parseEnvLevel(): LogLevel {
const env = process.env.ENSEMBL_LOG_LEVEL?.toUpperCase();
if (env && env in LogLevel) {
return LogLevel[env as keyof typeof LogLevel] as unknown as LogLevel;
}
return LogLevel.INFO;
}
private log(
level: LogLevel,
event: string,
data?: Record<string, unknown>
): void {
if (level < this.level) return;
const entry = {
timestamp: new Date().toISOString(),
level: LOG_LEVEL_NAMES[level],
event,
...data,
};
process.stderr.write(JSON.stringify(entry) + "\n");
}
debug(event: string, data?: Record<string, unknown>) {
this.log(LogLevel.DEBUG, event, data);
}
info(event: string, data?: Record<string, unknown>) {
this.log(LogLevel.INFO, event, data);
}
warn(event: string, data?: Record<string, unknown>) {
this.log(LogLevel.WARN, event, data);
}
error(event: string, data?: Record<string, unknown>) {
this.log(LogLevel.ERROR, event, data);
}
}
export const logger = new Logger();
