Unable to inject winston's logger instance with NestJS - node.js

Question

I'm using NestJS 7.0.7 and Winston 3.2.1 (with nest-winston 1.3.3).
I'm trying to integrate Winston into NestJS, but so far, I'm unable to inject a logger instance (to actually log anything) into any controller/service.
Since I would like to use Winston across the application AND during bootstrapping, I'm using the approach as the main Nest logger:
// main.ts
import { NestFactory } from "#nestjs/core";
import { WinstonModule } from "nest-winston";
import { format, transports } from "winston";
import { AppModule } from "./app.module";
async function bootstrap(): Promise<void> {
const app = await NestFactory.create(AppModule, {
logger: WinstonModule.createLogger({
exitOnError: false,
format: format.combine(format.colorize(), format.timestamp(), format.printf(msg => {
return `${msg.timestamp} [${msg.level}] - ${msg.message}`;
})),
transports: [new transports.Console({ level: "debug" })], // alert > error > warning > notice > info > debug
}),
});
app.use(helmet());
await app.listen(process.env.PORT || 3_000);
}
bootstrap().then(() => {
// ...
});
I'm not doing anything in regard to the logging in app.module.ts:
// app.module.ts
import { SomeController } from "#controller/some.controller";
import { Module } from "#nestjs/common";
import { SomeService } from "#service/some.service";
#Module({
controllers: [SomeController],
imports: [],
providers: [SomeService],
})
export class AppModule {
// ...
}
// some.controller.ts
import { Controller, Get, Inject, Param, ParseUUIDPipe, Post } from "#nestjs/common";
import { SomeService } from "#service/some.service";
import { WINSTON_MODULE_PROVIDER } from "nest-winston";
import { Logger } from "winston";
#Controller("/api/some-path")
export class SomeController {
constructor(#Inject(WINSTON_MODULE_PROVIDER) private readonly logger: Logger, private readonly service: SomeService) {
// ...
}
...
}
The application tries to start but fails at some point:
2020-04-06T18:51:08.779Z [info] - Starting Nest application...
2020-04-06T18:51:08.787Z [error] - Nest can't resolve dependencies of the SomeController (?, SomeService). Please make sure that the argument winston at index [0] is available in the AppModule context.
Potential solutions:
- If winston is a provider, is it part of the current AppModule?
- If winston is exported from a separate #Module, is that module imported within AppModule?
#Module({
imports: [ /* the Module containing winston */ ]
})

Answer 1

Try importing the WinstonModule in the root AppModule, as explained in the official docs: https://github.com/gremo/nest-winston:
import { Module } from '#nestjs/common';
import { WinstonModule } from 'nest-winston';
import * as winston from 'winston';
const logger: LoggerConfig = new LoggerConfig();
#Module({
imports: [WinstonModule.forRoot(logger.console())],
})
export class AppModule {}
It's probably a good idea to create some kind of factory/Logging-Config in order not to have to duplicate the logger options.
import winston, { format, transports } from "winston";
export class LoggerConfig {
private readonly options: winston.LoggerOptions;
constructor() {
this.options = {
exitOnError: false,
format: format.combine(format.colorize(), format.timestamp(), format.printf(msg => {
return `${msg.timestamp} [${msg.level}] - ${msg.message}`;
})),
transports: [new transports.Console({ level: "debug" })], // alert > error > warning > notice > info > debug
};
}
public console(): object {
return this.options;
}
}

Answer 2

Implement Winston custom logger in NestJs project
Prerequisit:
npm install --save nest-winston winston winston-daily-rotate-file
import { NestFactory } from '#nestjs/core';
import { WinstonModule } from 'nest-winston';
import * as winston from 'winston';
import * as winstonDailyRotateFile from 'winston-daily-rotate-file';
import { AppModule } from './app.module';
const transports = {
console: new winston.transports.Console({
level: 'silly',
format: winston.format.combine(
winston.format.timestamp({
format: 'YYYY-MM-DD HH:mm:ss',
}),
winston.format.colorize({
colors: {
info: 'blue',
debug: 'yellow',
error: 'red',
},
}),
winston.format.printf((info) => {
return `${info.timestamp} [${info.level}] [${
info.context ? info.context : info.stack
}] ${info.message}`;
}),
// winston.format.align(),
),
}),
combinedFile: new winstonDailyRotateFile({
dirname: 'logs',
filename: 'combined',
extension: '.log',
level: 'info',
}),
errorFile: new winstonDailyRotateFile({
dirname: 'logs',
filename: 'error',
extension: '.log',
level: 'error',
}),
};
async function bootstrap() {
const app = await NestFactory.create(AppModule);
app.useLogger(
WinstonModule.createLogger({
format: winston.format.combine(
winston.format.timestamp({
format: 'YYYY-MM-DD HH:mm:ss',
}),
winston.format.errors({ stack: true }),
winston.format.splat(),
winston.format.json(),
),
transports: [
transports.console,
transports.combinedFile,
transports.errorFile,
],
}),
);
await app.listen(4000);
}
bootstrap();
NestJs Custom Logger
NestJs Winston NPM Documentation
Note Log Levels, file names, dateformat you may edit as per your requirement. Follow officials documentations with more option.