@janiscommerce/log

log

A package for creating logs in Firehose

📦 Installation

npm install @janiscommerce/log

🔧 Configuration

ENV variables

JANIS_SERVICE_NAME (required): The name of the service that will create the log. JANIS_ENV (required): The stage name that will used as prefix for trace firehose delivery stream. LOG_ROLE_ARN (required): The ARN to assume the trace role in order to put records in Firehose. JANIS_TRACE_EXTENSION_ENABLED: If this variable is set, logs will be attempted to be buffered in the Janis Trace Extension server. If the server fails, direct call to Firehose is the fallback.

API

add(clientCode, logs)

Parameters: clientCode [String], logs [Object] or [Object array] Puts the received log or logs into the janis-trace-firehose or local server

Log structure

The log [Object] parameter have the following structure:

• id [String] (optional): The ID of the log in UUID V4 format. Default will be auto-generated.
• client [String] (optional): The client code of the log owner. If set, this overrides the clientCode parameter of the add() method.
• service [String] (optional): The service name, if this field not exists, will be obtained from the ENV (JANIS_SERVICE_NAME)
• entity [String] (required): The name of the entity that is creating the log.
• entityId [String] (optional): The ID of the entity that is creating the log.
• type [String] (required): The log type.
• message [String] (optional): A general message about the log.
• userCreated [String] (optional): The user that creates the log.
• dateCreated [ISODate] (optional): The date when the log was created.
• log [Object|Array] (optional): This property is a JSON that includes all the technical data about your log. If Array was received, will be transformed as an Object.
  • log.functionName [String]: This field will be completed with ENV variable JANIS_FUNCTION_NAME. The variable is created in package @janiscommerce/lambda
  • log.apiRequestLogId [String]: This field will be completed with ENV variable JANIS_API_REQUEST_LOG_ID. The variable is created in package @janiscommerce/api

createTracker(clientCode)

Parameters: clientCode [String] Create a new tracker to build an incremental log. It returns a LogTracker instance.

sendToTrace(logs)

Parameters: logs [Array<LogData>] Sends the received logs directly to a Firehose instance, skipping local server check. Logs have the same structure as in the add()method, but with theclient` property being required.

Log Tracker

A log tracker is an object used to build an incremental log to track multiple states of a process. For example, if when you publish a product you can track the initial state of the product, then request that will be made and the response received. Finally you save everything in a log to keep track for debugging purposes.

To use a log tracker, you have to call the Log.createTracker() method, which will return an instance of a tracker. Then you can make as much calls to logTracker.add() as you want. When you're ready to save the log, simply call the logTracker.log() method.

Each time you call the log() method, the internal state is reset so you can re-use the instance in case you want to.

See the Log Tracker API below:

add(name, data)

Parameters: name [String], data [Object] Saves the data object associated with a name that explains what it is.

log(logData)

Parameters: logData [LogData]. Saves the log with the properties passed as LogData. These are the same that are passed to Log.add(), except for the log property that will be overridden.

Errors

The errors are informed with a LogError. This object has a code that can be useful for a correct error handling. The codes are the following:

Code	Description
1	Invalid log
2	Firehose Error
4	Assuming STS role error

• Error code: 3 removed since 3.5.1

Usage

Adding basic log

const Log = require('@janiscommerce/log');

// Single log send
await Log.add('some-client', {
  service: 'oms',
  entity: 'api',
  entityId: 'order',
  type: 'api-request',
  dateCreated: '2020-04-21T17:16:01.324Z',
  log: {
    api: {
      endpoint: 'order/5ea1c7f48efca3c21654d4a3/pick-items',
      httpMethod: 'post'
    },
    request: {
      headers: {
        accept: 'application/json',
        'content-type': 'application/json',
        Host: 'oms.host.com',
        'janis-client': 'some-client',
        'X-Amzn-Trace-Id': 'Root=1-fca3c2-5ea1c7f48efca3c21654d4a3',
        'X-Forwarded-For': '12.354.67.890',
        'X-Forwarded-Port': '123',
        'X-Forwarded-Proto': 'https'
      },
      data: {
        0: {
          pickedQuantity: 1,
          pickingSessionId: '5ea1c88463d91e9758f2c1b8',
          pickerId: '5ea1c8895ebb38d472ccd8c3',
          id: '5EA1C88D6E94BC19F7FC1612',
          pickedEans: [
            '1234567890'
          ]
        }
      }
    },
    response: {
      code: 200,
      headers: {},
      body: {}
    },
    executionTime: 868.251946
  }
});

Adding multiple logs in the same request

const Log = require('@janiscommerce/log');

// Multiple logs send
await Log.add('some-client', [{
  service: 'catalog',
  entity: 'account',
  entityId: '5ea1c8c53fdac68fb60eac9e',
  type: 'upserted',
  dateCreated: '2020-04-22T22:03:50.507Z',
  log: {
    id: '5ea1c8c53fdac68fb60eac9e',
    referenceId: 'rv-000005'
  }
}, {
  service: 'catalog',
  entity: 'account',
  entityId: '5ea1c8cd11f82560a364cbd4',
  type: 'upserted',
  dateCreated: '2020-04-22T22:03:50.507Z',
  log: {
    id: '5ea1c8cd11f82560a364cbd4',
    referenceId: 'rf-00752'
  }
}]);

Create LogTracker

const Log = require('@janiscommerce/log');

// Incremental logs, during a map-reduce operation
const logTracker = Log.createTracker('some-client');

const numbers = [1, 2, 3];
logTracker.add('initialState', numbers);

const doubledNumbers = numbers.map(n => n * 2);
logTracker.add('intermediateState', doubledNumbers);

const sum = doubledNumbers.reduce((total, n) => total + n, 0);
logTracker.add('finalState', sum);

await logTracker.log({
  entity: 'math',
  entityId: 'someId',
  type: 'map-reduce',
  message: 'Map reduced to sum the double of some numbers'
});

Serverless configuration

Returns an array with the hooks needed for Log's serverless configuration according to Serverless Helper. In path/to/root/serverless.js add:

'use strict';

const { helper } = require('sls-helper'); // eslint-disable-line
const functions = require('./serverless/functions.json');
const Log = require('@janiscommerce/log');

module.exports = helper({
	hooks: [
		// other hooks
    ...functions,
    ...Log.serverlessConfiguration
	]
});

Changelog

[3.6.0] - 2022-11-10

Added

• Trace Layer support for local log buffering