Logging on steroids

Escriba

The motivations for this library is to provide ways for a better express application logging. To achieve this goal we provide tools to managing logs, a log tracker across services and we add relevant information to your log.

Cool features

• JSON format
• Unique id
• Request and responses share the same id. This enables tracking the path of a request across your services
• Hide secret information based on regex
• Adds extra information to your logs as pid, hostname, level, startTime, and latency
• Filter props from request and/or response
• Skip routes based on methods/rules/body props

Installation

npm install --save escriba

Usage

Escriba provides two kinds of logger: logger and httpLogger.

Logger

Use logger log across your application.

For example, to log some information from an userController hidding the password property:

const log4js = require('log4js').getLogger()
const escriba = require('escriba')
const cuid = require('cuid')

log4js.level = 'info'

const { logger } = escriba({
  loggerEngine: log4js,
  service: 'api',
  sensitive: {
    password: {
      paths: ['message.password'],
      pattern: /\w.*/g,
      replacer: '*'
    }
  }
})

logger.info({ text: 'Setting user permission', password: 'abc' }, { id: cuid(), from: 'userController' })

Http logger

Use httpLogger to log an http request and response.

For this example we'll long only some properties: id, body and statusCode.

We'll also skip status route, options method and body property from routes that end with .csv or .xlsx.

It's important to hide sentive information like api_key.

const express = require('express')
const log4js = require('log4js').getLogger()
const escriba = require('escriba')
const cuid = require('cuid')
const roomController = require('./controllers/room')

const app = express()

const { httpLogger } = escriba({
  loggerEngine: log4js,
  sensitive: {
    password: {
      paths: ['body.api_key'],
      pattern: /(ak_test|ak_live).*/g,
      replacer: '*'
    }
  },
  httpConf: {
    logIdPath: 'headers.my_path_id',
    propsToLog: {
      request: ['id', 'url', 'body'],
      response: ['id', 'url', 'body', 'statusCode', 'latency']
    },
    envToLog: ['SHELL', 'PATH'],
    skipRules: [
      {
        route: /\/status/,
        method: /.*/,
        onlyBody: false
      },
      {
        route: /.*\.(csv|xlsx)$/,
        method: /GET/,
        onlyBody: true
      },
      {
        route: /.*/,
        method: /OPTIONS/,
        onlyBody: false
      }
    ],
    propMaxLength: {
      body: 2048,
      url: 1024
    },
    propsToParse: {
      request: {
         'id': String,
         'body.document_number': Number,
      },
      response: {
         'body.customer.id': Number
      }
    }
  }
})

app.use(httpLogger)

app.get('/room/:id', roomController.index)
app.post('/room', roomController.save)

Every request and response will be logged, and the coolest part: both will have the same id. This is important because you can search for this id and get all information about your request and response.

As you can see we have the logIdPath inside the httpConf object. This property allow you to pick log id from a desired path in request object. If you don't pass this property escriba will generate a new id for your request/response logs using cuid.

This id is injected in the req object, so if you need to log some extra information between a request and response just do something like this:

logger.info('some controller information', { id: req.id })

Also it's possible to skip logs or only the body property through skipRules, in the example we are skiping logs from route /status for all methods and skiping the body property from routes that ends with .csv or .xlsx.

The propMaxLength attribute is responsible to limit the number of characters for certain properties if they exist within propsTolog definition.

The propsToParse attribute is responsible to parse any atribute based on a path, the parsing works by providing a valid javascript native Function (e.g String, Number etc).

Masks

Just like the loggerEngine option, escriba accepts two types of mask engines, they are iron-mask and mask-json. If you don't pass any maskEngine, iron-mask will be used as default.

iron-mask

const { logger, httpLogger } = escriba({
  loggerEngine,
  service: 'bla',
  // no `maskEngine` informed, `iron-mask` will be used
  sensitive: { // `iron-mask` sensitive format
    secret: {
      paths: ['message.secret', 'message.metadata.secret', 'body.secret'],
      pattern: /\w.*/g,
      replacer: '*',
    },
  },
})

mask-json

const maskJson = require('mask-json')
const { logger, httpLogger } = escriba({
  loggerEngine,
  service: 'bla',
  maskEngine: maskJson,
  sensitive: { // `mask-json` sensitive format
    blacklist: ['secret'],
    options: {
      replacement: '*',
    },
  },
})

Integrations

You can enable integrations by simply passing a integrations key in the config. Like this:

escriba({
  integrations: {
    datadog: true
  }
})

But remember, for each integration to work you may need to configure your application via environment variables.

Datadog

You'll need to install dd-trace in your application. The Datadog integration enable this feature: https://docs.datadoghq.com/tracing/advanced/connect_logs_and_traces/.

Examples

The log-generator inside examples folder will run a Node.js application that will make a request for itself every in an interval defined by the user (in milliseconds). The application will get input values from an environment variable ESCRIBA_TIMEOUT(3000 is the default value, this represents 3 seconds)

To use log-generator through Docker use these commands inside the log-generator folder:

docker build -t pagarme/log-generator:latest .

docker run -e ESCRIBA_TIMEOUT=3000 -p 3000:3000 -d -v $(cd ../../ && pwd):/log-generator/node_modules/escriba pagarme/log-generator:latest

And to make some manual requests use:

curl -H "Content-Type: application/json" -X GET http://localhost:3000/escriba

curl -H "Content-Type: application/json" -X POST -d '{"username":"a name"}' http://localhost:3000/escriba

The log-generator example will get Escriba library from npm. If you want to get the library directly from the repository run docker with -v:

docker run -e ESCRIBA_TIMEOUT=3000 -p 3000:3000 -d -v $(cd ../../ && pwd):/escriba pagarme/log-generator:latest

License

The MIT License (MIT)
Copyright (c) 2017 Pagar.me Pagamentos S/A