@ensono-stacks/logger

The @ensono-stacks/logger plugin allows you to add industry standard logging functionality to your Ensono Stacks apps.

Currently, the following logging libraries are supported:

• winston

Setting up @ensono-stacks/logger

Prerequisites

An existing Ensono Stacks workspace.

Installation

Install the @ensono-stacks/logger with the following command:

npm

npm install --save-dev @ensono-stacks/logger@latest

yarn

yarn add --dev @ensono-stacks/logger@latest

Executors and Generators

To see a list of the plugin capabilities run the following command:

nx list @ensono-stacks/logger

View additional information about a plugin capability through the following command:

nx g @ensono-stacks/logger:[generator-executor-name] --help

Generators

@ensono-stacks/logger:winston

Add Winston to your project

Generates a new Nx library which contains a Winston logger instance and associated config.

Prerequisites

An existing Ensono Stacks workspace.

Usage

nx g @ensono-stacks/logger:winston

Command line arguments

The following command line arguments are available:

Option	Description	Type	Accepted Values	Default	Available in interactive prompt?
--name	Name of the generated library	string		N/A	Yes
--tags	Add tags to the project (used for linting)	string		N/A
--directory	Directory where the project is placed (within Nx libs directory)	string		N/A
--skipFormat	Skip formatting files	boolean	true/false	false
--logLevelType	The type of log levels that will be used	enum	cli/syslog/npm	npm	Yes
--consoleLogs	Output logs to the console	boolean	true/false	false
--fileTransportPath	File path used for logs transport	string		N/A
--httpTransport	Add a http transport	boolean	true/false	false
--httpTransportHost	Remote host of the HTTP logging endpoint	string		N/A
--httpTransportPort	Remote port of the HTTP logging endpoint	number		N/A
--httpTransportPath	Remote URI of the HTTP logging endpoint	string		N/A
--httpTransportSSL	Use SSL for the HTTP logging endpoint	boolean	true/false	false
--streamPath	Stream transport path	string		N/A

Generator Output

The generator will create a new application within your libs folder with the following structure:

.
├── libs/[libname]
│   ├── src
│   ├── ├── index.ts // Contains the Winston configuration and creates the logger instance
│   ├── ├── index.test.ts // Tests for the logger
│   ├── .eslintrc.json // ESLint config - extends from workspace config
│   ├── jest.config.ts // Jest config - extends from workspace config
│   ├── project.json // Nx config file for the library
│   ├── tsconfig.json // Main Typescript config for the library - extends workspace config & references the below two tsconfig files
│   ├── tsconfig.lib.json // Typescript config for the library's source files (excluding tests)
│   ├── tsconfig.spec.json // Typescript config for the library's test files
│   ├── README.md // Information on the library and how to run scripts
├── jest.config.ts // Workspace-level Jest config - created if this does not already exist
└── jest.preset.ts // Workspace-leve Jest preset that extends `@nx/jest/preset` - created if this does not already exist.

Additionally, the following files will be modified

.
├── nx.json // Adds configuration for Jest tests if this has not already been done by another generator
├── package.json // Adds winston as a dependency
└── tsconfig.base.json // Adds new library into `paths` field

Importing the logger into your app

Having created a logger using the above command, import the Winston logger instance from the newly created library (the import name can be found within the tsconfig.base.json files paths field) into your application:

import logger from '@workspace-name/mynewlogger'

logger.log({
    level: 'info',
    message: 'I love Ensono Stacks!', 
})

note

You would need to change the @workspace-name to the name of your workspace

To change how Winston is configured, edit the created library:

const logger = winston.createLogger(logConfiguration);

// Custom transport for non-production
if (process.env.NODE_ENV !== 'production') {
    logger.add(new winston.transports.Console({
        format: winston.format.simple(), 
    })) 
} 
 
export default logger;

Log Levels

Winston provides several log levels that you can use to categorize and filter log messages. These log levels are commonly used in many logging libraries and provide a way to prioritize and categorize log messages based on their severity.

By default Winston uses the following npm log levels:

• error: Used to log errors and exceptions. This log level is for critical issues that require immediate attention.

• warn: Indicates a potential issue or warning that does not necessarily disrupt the application but should be noted.

• info: This is the default log level and is used for general information about the application's operations. It's often used to log major events or milestones.

• http: Logs HTTP related messages, such as host, path and response/request details.

• verbose: A step above debug, providing more detailed information but not as noisy as silly or debug.

• debug: Used for debugging and providing additional information about the application's state and behavior.

• silly: The lowest log level, often used internally for debugging and tracing purposes.

For more information on log level severity please refer to the log levels section of the Winston documentation.

Other resources

Documentation for Winston can be found here.