Package Exports

gc-json-logger-express
gc-json-logger-express/dist/index.js

This package does not declare an exports field, so the exports above have been automatically detected and optimized by JSPM instead. If any package subpath is missing, it is recommended to post an issue to the original package (gc-json-logger-express) to support the "exports" field. If that is not possible, create a JSPM override to customize the exports field for this package.

Readme

Structured logging for express.js app in GKE

Health License

Precaution

The logger makes use of async_hooks module which is currently experimental. However, the use of async_hooks mechanism was at basic.

Installation

npm install --save gc-json-logger gc-json-logger-express

yarn add gc-json-logger gc-json-logger-express

View in Google Cloud Logging

Google Cloud Logging

Integration

const { Logger, Severity } = require('gc-json-logger');
const { log } = require('gc-json-logger-express');
const express = require('express');

const app = express();

/* Set desired application log level */
Logger.setLevel(Severity.DEBUG);

/* Filter sensitive data or transform log entry */
app.use(
  log((_req, _res, entry) => {
    const severity = entry.meta.httpRequest?.status >= 500 ? Severity.ERROR : entry.severity;
    return { ...entry, severity };
  })
);

app.use(express.text());
app.use(express.json());
app.use((req, res) => res.status(500).send(req.body));

app.listen(3000);

Mock Request

curl -X POST "http://localhost:3000/echo" \
  -H "Content-Type: text/plain" \
  -d 'Hello world!'

Logged Request

{
  "severity": "INFO",
  "timestamp": "2022-01-01T00:00:00.000Z",
  "message": "200 POST /echo",
  "httpRequest": {
    "protocol": "HTTP/1.1",
    "requestSize": "141",
    "remoteIp": "::ffff:127.0.0.1",
    "requestUrl": "http://localhost:3000/echo",
    "requestMethod": "POST",
    "userAgent": "curl/7.79.1",
    "serverIp": "::ffff:127.0.0.1:3000"
  },
  "logging.googleapis.com/operation": {
    "id": "135af3bd-1cde-4b72-92ac-3106e7514714"
  }
}

Logged Request and Response

{
  "severity": "ERROR",
  "timestamp": "2022-01-01T00:00:00.000Z",
  "message": "500 POST /echo (13ms)",
  "httpRequest": {
    "latency": "13ms",
    "responseSize": "258",
    "status": 500
  },
  "logging.googleapis.com/operation": {
    "id": "135af3bd-1cde-4b72-92ac-3106e7514714"
  },
  "meta": {
    "request": {
      "headers": {
        "host": "localhost:3000",
        "user-agent": "curl/7.79.1",
        "accept": "*/*",
        "content-type": "text/plain",
        "content-length": "12"
      },
      "body": "Hello world!"
    },
    "response": {
      "headers": {
        "x-powered-by": "Express",
        "content-type": "text/html; charset=utf-8",
        "content-length": "12",
        "etag": "W/\"c-00hq6RNueFa8QiEjhep5cJRHWAI\""
      },
      "body": "Hello world!"
    }
  }
}