MailBots Logger

A custom logger for the monitoring tools we use internally at FollowUpThen and MailBots: – Datadog and LogDNA.

LogDNA gets logs for debugging. The logger turns log events into datadog metrics, allowing us to view frequency of log events in dashboards, alerts and enable anomoly detection, etc.

Usage

const Logger = require("@mailbots/logger");
const logger = new Logger({
  logDnaKey: process.env.LOGDNA_KEY,
  logDnaHost: process.env.LOGDNA_HOSTNAME,
  logDnaApp: process.env.LOGDNA_APPNAME,
  ddAppKey: process.env.DATADOG_APP_KEY,
  ddApiKey: process.env.DATADOG_API_KEY,
  ddMetricsPrefix: process.env.DATADOG_METRICS_PREFIX || "", // to keep microservice metrics organized
  logToConsole: process.env.LOG_TO_CONSOLE // log to console.log. Pass "short" not pass extra data
});

// A simple log message
logger.log("a simple log message");

Set Logging Context

Set context from webhook. Every subsequent log event in that the request shares this context, allowing for searching by userid or session-id.

logger.setContextFromWebhook(webhook);

You can also set logging context from the AWS Lambda context object.

logger.setLambdaContext(context);

Caution: Data Types

When passing debug data in the data param, data types need to remain consistent (LogDNA requirement for their indexing feature). As a convention, always imply the datatype of the debug var in the key name.

logger.log("a log message", { level: "info", data: { debug_str: "data" } });

Debugging

Run tests with DEBUG=@mailbots/logger to tests our parts and datadog. Runt tests with NODE_DEBUG=logdna to see logdna output.

Here's an .env template to copy / paste:

LOGDNA_KEY=
LOGDNA_HOSTNAME=
LOGDNA_APPNAME=
NODE_ENV=

DATADOG_API_KEY=
DATADOG_APP_KEY=
DATADOG_METRICS_PREFIX=

Available logging services

Besides logging the message to the console, the library also sends it to our third-party logging services:

• LogDna
• DataDog

A log message can opt out of individual services by passing a boolean param to the options object:

logger.log("a log message", { datadog: false, logdna: false });