send Nestjs logs to Grafana Loki using winston

Question

I want to send all my Nestjs logs to Grafana, using a winston logger service. I tried multiple things, but none of them is working...

// main.ts

 const logger = new LoggerService();
  const app = await NestFactory.create(AppModule, {
    logger: logger,
  });
  app.useLogger(logger);

// logger.service.ts
import { LoggerService as LS } from '@nestjs/common';
import winston from 'winston';
const { combine, timestamp } = winston.format;
import * as Transport from 'winston-transport';
import {
  utilities as nestWinstonModuleUtilities,
  WinstonModule,
} from 'nest-winston';
import LokiTransport from 'winston-loki';

export class LoggerService implements LS {
  private logger: LS;

  constructor() {
    this.logger = WinstonModule.createLogger({
      transports: this.logTransports(),
    });
  }

  private logTransports = () => {
    const logLevel = !!process.env.LOG_LEVEL ? process.env.LOG_LEVEL : 'error';

    const format = combine(
      timestamp({ format: 'YYYY-MM-DD HH:mm:ss' }),
      nestWinstonModuleUtilities.format.nestLike(),
    );

    const logTransports: Transport[] = [
      new LokiTransport({
        host: process.env.G_URL,
        basicAuth: `${process.env.G_USER}:${process.env.G_KEY}`,
        labels: { app: process.env.G_NAME },
        json: true,
        level: logLevel,
        format: winston.format.json(),
        replaceTimestamp: true,
        timeout: 10,
        onConnectionError: (err) => console.error(err),
      }),
      new winston.transports.Console({
        format: format,
        level: logLevel,
      }),
    ];

    return logTransports;
  };

  // + other functions (toPrettyJson, log, error, etc)
}

and my env variables are correct (ps: censored them using ...)

G_URL="https://logs-prod-....grafana.net"
G_NAME="grafanacloud-...-logs"
G_USER="8...5"
G_KEY="glc_eyJ...ifX0="
LOG_LEVEL='debug'

I also tried different ways of creating the transporst or logger, but none sending any logs to Grafana... I see logs in my console, formatted as expected though. No errors.

I also followed and tried all these things https://github.com/JaniAnttonen/winston-loki/issues/140, but with no success...

I also tried a local Docker Loki image, with no success of sending any logs into it. I also got timeout errors for that :)

Any ideas? Am I doing something wrong? Do I need to create a server, and use Grafana just for their UI & search capabilities? :thinking: