Logging is an essential part of any API development. It allows developers to quickly and easily track errors, identify performance issues, and gain insights into how an API is being used. NodeJS is an ideal platform for API logging, thanks to its powerful and reliable JavaScript runtime environment.

Many NodeJS packages are available to help developers get started, and here we will look at ten of the best. These packages provide a range of features and capabilities, from real-time monitoring and analytics to automatic log rotation and maintenance. With the right NodeJS package, developers can ensure that their API is well-logged and that any performance issues or errors are quickly identified and addressed.

Winston

Winston is one of the most popular and well-established NodeJS logging packages. Winston is compatible with all modern browser environments, including NodeJS, Meteor, and ReactJS. It supports all major logging and terminal services, including Amazon CloudWatch, Azure Log Analytics, Loggly Kubo, Google Cloud Logging, Splunk, and more.

There are more than 20 integrations available for Winston, including AWS, Azure, GCP, Heroku, Honeybadger, NewRelic, PagerDuty, Papertrail, Sentry, Slack, and Stackdriver. There are a number of different logging levels available to suit different environments and use cases. Similarly, Winston also supports structured logging, with support for user-defined objects and data. Winston is great for API logging, particularly in a microservices environment. It’s reliable, scalable, and has a wealth of integrations and configuration options.

Morgan

Morgan is a minimalistic, zero-configuration logging library for NodeJS that uses console.log underneath. It is designed to be simple and unobtrusive while also being performant and easy to understand. The log levels are mapped to those used by AWS CloudWatch Logs — critical, error, warning, info, and debug.

Logs can be written to the console or stored in a file. By default, logs are written to the console, but a file can be specified by setting the log path property. Morgan also supports structured logging, which can either be disabled or used by setting the structured option to true.

Logging can also be disabled by setting the level to off. By default, logging is set to info. As with many logging packages, it is possible to configure the level of detail in the log output. This can be configured by setting the logLevel property to info, warn, error, or off. The level can also be set to custom, which allows you to use your own function to determine the log level.

Log4js

Log4js is a popular and mature NodeJS logging package. It can be used to create custom loggers and has a number of pre-built loggers that can be used out of the box, including Apache, Auth, Cricket, FTP, JDBC, Logger, Mail, and SMTP. Log4js has been around for a long time, but it’s still actively maintained and updated.

Log4j is a great choice for organizations with a lot of existing logging software. Log4js has built-in support for hierarchical logging, which allows loggers to be grouped together. This means that logs from separate applications can be combined on a single logging channel, making it easier to track down issues and resolve them quickly.

Pino

Pino is a high-performance, lightweight logging library for NodeJS. It’s designed to be simple, fast, and easy to use. Pino is designed to work equally well in both production and development environments and can be configured to work with all major logging services. Pino supports structured logging, which is a great way to capture structured data in your logs, whether they’re used for debugging or analytics.

Pino has a minimalistic design and can be customized using a filter function. It also supports context-based logging, which allows logs to be written based on a certain level of importance. It also has several built-in filters, including Console, File, Fluentd, Gelf, and Syslog. When writing logs, users can choose between Fluent, which uses a call-by-value style, and Fluent-style, which uses call-by-reference.

Bunyan

Bunyan is a high-performance, lightweight logging library for NodeJS. It is designed to be fast, simple, and easy to use, with a minimal configuration approach. It supports structured logging, which is a great way to capture and track data with your logs. Bunyan’s configuration is very simple, with just three options — the log directory, the log level, and the log format. Bunyan’s log format is similar to JSON, which makes it very easy to read, interpret, and use your logs for debugging and analytics.

It supports custom loggers and can be used to build multi-module applications. It can also be used with other logging libraries, like Log4js or Pino. It also supports asynchronous logging, making it easy to write highly performant logging code.

Signals

Signals is a lightweight, low-configuration logging library for NodeJS. It has a very simple and minimalistic design, with just three options — log level, log function, and log file. A log file can be specified by setting the logFile option, while the log level can be set to either info, debug, warn, or error. The log function can be set to either console.log, console.warn, console.info, console.error, console.debug, or process.log. It logs to process.stderr by default, but it can also be configured to write to a file. Signals is designed to be easy to use while being lightweight and scalable.

Tracer

Tracer is a mature and robust logging library for NodeJS. It supports both plain text and structured logging, which is a great way to track data with your logs. It also supports asynchronous logging, which makes it easy to write highly performant code. It can be configured to log to a file or to the terminal. It can also be used to build multi-module applications. Tracer can be used with other logging libraries, like Log4js or Bunyan. Additionally, it supports automatic log rotation, with the ability to set how long logs should be kept.

Npmlog

Npmlog is an open-source and lightweight logging library for NodeJS, written in C. It supports structured logging, which is a great way to capture and track data with your logs. It can be used to build multi-module applications, and it can also be used with other logging libraries, like Bunyan. Additionally, Npmlog supports automatic log rotation. Npmlog has a simple configuration, with just three options — log level, log directory, and log format.

Frontail

Frontail is a robust and scalable logging library for NodeJS. It has been battle-tested in production environments and has been used by organizations like Netflix and Shopify. It is used by many large organizations that require a highly scalable and reliable logging solution. It supports structured logging, which is a great way to capture and track data with your logs.

Frontail also supports multi-line logs, which are helpful when debugging complicated issues. By default, logs are written to the console, but they can be configured to be written to a file. Logs can also be sent to a variety of different services, including Amazon CloudWatch, Papertrail, and Syslog.

Loglevel

Loglevel is a lightweight and flexible logging library for NodeJS. It supports plain text logging, structured logging, and JSON logging. It can be used to build multi-module applications, and it can also be used in conjunction with other logging libraries. Additionally, Loglevel supports automatic log rotation.

Final Words

All of these packages have their own benefits and drawbacks, so it’s worthwhile to install a few on your system to decide which one is right for you. There are many NodeJS logging packages to choose from, but any of the ones mentioned above can get the job done for most scenarios.