@pagopa/logger-express

@pagopa/logger adapter for express, inspired by morgan

this package includes two middlewares:

• logger to decorate express.Request with a log function
• access to enable HTTP request logs

How to use it

Declare your concrete implementation of the logger

// my-logger.ts

import * as L from "@pagopa/logger";

const ConsoleLogger: L.Logger = {
  log: (r) => () => console.log(r),
  format: L.format.json,
};

Use it in your express app

import express from "express";

import * as L from "@pagopa/logger";
import { logger, access } from "@pagopa/logger-express";

import { ConsoleLogger } from "./my-logger";

const app = express();

// decorate "req" with "log" function
app.use(logger(ConsoleLogger));

// enable HTTP request logging
app.use(access());

app.get("/", (req, res) => {
  // logs with "info" level and name in context
  req.log?.("info", "Hello!!", {
    name: req.query.name,
  });
  res.json({
    message: "it works!",
  });
});

app.listen(3000);

The access middleware supports a skip option

app.use(
  access({
    // skip successful response
    skip: (req, res) => res.statusCode === 200,
  })
);