To manage several clients simultaneously, Node.js employs the “Single Threaded Event Loop” design. To understand how this differs from other runtimes, we must realize how concurrent multi-threaded clients handle in languages like Java.Multiple clients send requests in a multi-threaded request-response architecture, and the server processes each individually before delivering the response. However, handling concurrent calls requires the usage of several threads. Each time a request is received, one of these threads that are defined in a thread pool is given the task of handling it.Node.js operates uniquely. Let’s take a look at each stage it undergoes:
- Node.js keeps up a small thread pool to handle requests.
- Node.js adds new submissions to a queue as they arrive.
- The fundamental element, the single-threaded “Event loop,” now enters the picture. This event loop continuously awaits requests.
- When a request is received, the loop retrieves it from the queue and determines whether a blocking input/output (I/O) action is necessary. If not, it handles the inquiry and responds.
- The event loop selects a thread from the internal thread pool to handle the request if it requires a blocking operation. Internal lines are only sometimes available. The worker group is the collective name for these auxiliary threads.
- Once the blocking operation has been completed, the event loop monitors blocking requests and adds them to the queue. It keeps being non-blocking in this way.
Task execution is sped up because Node.js requires fewer threads and fewer resources/memory. This single-threaded programming design is identical to multi-threaded architecture. Java and other multi-threaded languages make more sense for handling data-intensive jobs, and Node.js is the clear choice for real-time applications.
The growth of Node.js can be attributed easily to its vast number of features, including:
- Simplicity—It is pretty simple to learn. Node.js is a popular option for novices in web development, and the extensive community and abundance of tutorials make getting started quite simple.
- Scalability—Node.js offers enormous application scalability. Due to its single-threaded nature, Node.js can efficiently handle a large number of connections at once.
- Speed—It is quick and effective, thanks to non-blocking thread execution.
- Packages—There are a variety of open-source Node.js packages that can make your work easier. The NPM ecosystem now has more than a million packages.
- Robust backend—Node.js is fast and offers capabilities like networking support because it is written in C and C++.
- Multiple Platforms—Support with Node.js enables you to build SaaS websites, desktop applications, and even mobile applications.
Many different applications use Node.js. Let’s look at some everyday use cases:
- Chat—This is a common real-time, multi-user application implemented in Node.js with WebSocket and IRC. The chat program has simple processing/computation requirements but is lightweight, data-intensive, and highly trafficked. The ideal use case for Node.js, it functions across distributed devices. Chat is an excellent use case for learning because it is straightforward while still including most of the conventions you encounter in a regular Node.js application.
- API on Top of an Object DB—The data from object DBs can be exposed naturally using Node.js (e.g., MongoDB). Node.js may operate without impedance mismatch and data conversion when using data that is stored in JSON format.
- Data Streaming—Streaming data can be done using Node.js. HTTP requests and responses are streams, but on more conventional web systems, they are handled as discrete events. Our ability to design some cool Node.js features can be based on this observation. For instance, we could process files as they are being submitted and process the incoming data in parallel during that upload process as it comes in through a stream. Both proxying between different data sources and real-time audio or video transcoding adhere to this.
- Proxy—Node.js is simple to use as a server-side proxy since it can manage numerous connections simultaneously in a nonblocking fashion. It helps collect data from multiple source points or proxying various services with diverse response times.
- Internet of Things—IoT applications typically include several sensors since they frequently deliver little data packets that can accumulate into a vast number of requests. Node.js is an excellent choice because it can swiftly handle numerous concurrent requests.
One of the greatest strengths of Node.js is its community. Node.js is developed and maintained by a passionate group of contributors and collaborators. It operates as an open-source project under the OpenJS Foundation
Regarding tools, Node.js has one thing you can count on: Options. Node’s popularity has led to it becoming an expected platform for all development tooling, which means that your options are vast regarding tooling. Let’s look at some standard picks.
.NPM is different fromnot being what it is because if not for the Node package manager (NPM). NPM consists of an online repository of open-source Node.js projects and a command line tool for installing those projects in your environment. According to Module Counts
, as of May 2022, NPM is approaching 2 million packages available. This is the largest repository on the list, and Java’s Maven Central is a distant second with less than 500,000.There are packages available for almost any task needed in an application. Simply go to NPM
and search for what you need. Once you find a suitable package, merely use the npm command from the command line in your node project, and the box and all its dependencies are automatically downloaded and installed. It could not be easier.
Whether building a new application or transforming an existing one, your DevOps process and tooling will be critical to the initial project’s success and future enhancements. Because Node.js is not a traditional compiled language, it lends itself naturally to DevOps concepts such as Continuous Integration (CI) and Continuous Delivery/Deployment (CD).A typical environment we would set up for a transformation project would start with source control. Git
, whether using a local repository or a cloud-based repository such as GitHub
, is the standard for Node.js source control.Next would be an automated testing environment. This would include unit testing, integration testing, and end-to-end testing.For unit and integration testing, a prevalent choice is to use the Mocha framework
in conjunction with an assertion library like Chai
. Using these tools, every Node.js module and function can be tested, and success/failure can be reported from a command line. This allows for the automation of low-level testing as soon as a change is committed to the repository.End-to-end testing will vary based on the interface of the Node.js application. For an API interface, tools such as Hippie
can be of use. For applications with a web-based user interface, the options are many. The selection of an instrument is generally based on budget and desired features.Lastly, an automation tool for the delivery/deployment of thoroughly tested and approved changes to various environments would be needed. A standard open-source option for this is Jenkins
In summary, Node.js is a well-known programming environment that may be used to create large-scale applications that must accommodate several concurrent requests. It is an excellent option for real-time and data-streaming applications due to its single-threaded, non-blocking I/O.Furthermore, Node.js has the world’s most famous open-source package repository, NPM, which now has over a million products. It also has a vast community of active developers.With Node.js, getting started is simple. All that’s left to do is think about how you’ll use and include Node.js in your stack now that we’ve gone through how to install and create a server in Node.js.Interested in learning more? See more on this topic here.