@pager/logger

@pager/logger

Structured logging for your verbose projects. Provides a pino logger with standard Pager defaults and redactions.

As of v7.0.0, no hapi plugin is exposed in this library. Hapi-based projects should use @pager/hapi-logger instead of this library. For an explanation of the split, see ADR-0015.

Basic usage

Provides a logger with standardized formatting and redaction configuration. For more details on how to work with Pino, take a look at its documentation or see configuration below for the setup details.

[!IMPORTANT]
Not for use in hapi projects, if your project uses hapi use @pager/hapi-logger instead of this library

Redacting

This library has been set up with an array of standard redactions based on current usage. Each app should explicitly append and detail all potential leaks. There are no wildcard defaults because there are large associated performance issues with wildcards, particularly intermediate wildcards. Please do your part in log security to ensure no PHI or secrets are leaked into the logs; defaults provided in the code are append only.

Environment

Name	Default	Description
LOG_LEVEL	info	Lowest level to log in this order: trace, debug, info, warn, error, fatal
LOG_ERROR_THRESHOLD	error	Lowest error to send to error transport
LOG_PRETTY_PRINT	none	Set to 1 to enable pretty print - this is not json and follows the configuration for prettyPrint docs

pino options

Pino default overrides per Pino's documentation.

{
  "level": "warn", // any pino default option overrides
  "redact": ['redactKey']
}

pino (Object)

Pino configuration object per Pino's documentation

instance (pino object)

Already configured pino object

Installation and Usage

// injecting a logger is best practice for most cases, defaulting to singleton is acceptable
const Logger = require('@pager/logger');

module.exports = (logger = Logger) => {

    Logger.info('Worker log');

    // .. worker works ...
    try {
        // do work
    }
    catch (err) {
        logger.error(err);
    }
};

Error handling

Under the hood we are using pino's default error serializer. This means it will add extra keys on the error object if present, and are not already used by one of pino's preset keys (e.g. data, message, type, etc.).

For example, see the custom field context within the error and it's expected log output:

const entity = { id: '6025827b568bb78e64b83ba2' };
const error = new Error('my error title');
error.context = { entityId: entity.id };
Logger.error(error);
/* Prints something like:
  {
    "level": 50,
    "time": 1613070971891,
    "pid": 58541,
    "hostname": "hostMBP",
    "context": {
      "entityId": "6025827b568bb78e64b83ba2"
    },
    "stack": "Error: my error title\n    at /projects/edge-api-cc/test/custom-error.js:19:23\n    at Immediate._onImmediate (/projects/edge-api-cc/node_modules/@hapi/lab/lib/runner.js:661:35)\n    at processImmediate (internal/timers.js:461:21)",
    "type": "Error",
    "data": "my error title"
  }
*/