Building microservices with Node js LogRocket Blog

We can add some additional components or layers in an MVC workflow to specifically manage the business logic and data access. The Model component represents the data, database interactions, and the business logic of the application. It is responsible for implementing the core business rules and application logic and also focuses on CRUD operations, data validation, and maintaining data integrity. It’s important to consider how this approach impacts the testability of our application, leading to longer development times as a consequence. At this point, you might be wondering how to tackle this challenge effectively and where to position your business logic in a clear and intelligent manner. Frameworks like Express.js offer incredible features for managing requests, views, and routes.

To address these limitations, Node.js provides a popular solution called promises. Serverless architecture, powered by services like AWS Lambda, Azure Functions, and Google Cloud Functions is a suitable choice for certain types of applications. It is particularly well-suited for event-driven, microservices-powered, async-tasks-rich, scalable, and cost-efficient apps.

Comparing Web Services and Service Bus

File servers are high-performance, relatively low cost, and easy to extend, but they require administration and security. In a client-server architecture, clients are viewed as consumers, whereas the server acts like a producer. A user or consumer sends a request to the server using a network medium, and then data is delivered to the user according to the submitted request. If the request is blocking then it will be passed to the thread pool otherwise it’s will process the simple request like I/O polling and returns the response to the client. NodeJS web server will receive the requests from the clients, these requests may contain the operations which are blocking or non-blocking.

• The server object is an EventEmitter, which means that we can emit multiple events on the server, such as listening, close, connection, error, and drop.
• It is particularly well-suited for event-driven, microservices-powered, async-tasks-rich, scalable, and cost-efficient apps.
• If the code of a class, function, or file becomes excessively lengthy, consider splitting it into smaller modules wherever possible and bundle them within related folders.
• Frameworks like Express.js offer incredible features for managing requests, views, and routes.
• You can serve your client side codes including other static files by locating them in public directory.
• The type of server that is created depends on what the method is listening to.

It can also make sites easier to use by storing personal preferences and information — for example reusing stored credit card details to streamline subsequent payments. Finally, we implement our GET route, which returns an aboutInfo  containing information about our application, as contained in the package.json file. Remember, we imported our package.json file on the second line of code in the about.js file. Server.js is the main file for our basic weather microservice app, as indicated in our package.json file.

Conduct unit testing

With such support, it can be tempting to place our business logic directly in our API routes. Unfortunately, this approach quickly leads to the creation of large, monolithic blocks that become unmanageable, difficult to read, and prone to decomposition in the long run. Now, we can delve into what I commonly refer to as the application structure node js development flow, which encompasses a set of rules and common practices aimed at enhancing the Node.js developer experience. The best practices outlined below can serve as a cheat sheet to assist you in establishing the ideal architecture flow for your upcoming project. In this tutorial, our focus will be the Node.js project structure and architecture.

For this reason, monolithic applications are neither flexible nor easily scalable; you cannot build features concurrently or achieve continuous deployment. While monolithic applications are not cost-effective to manage, they are cost-effective to build. Therefore, developers recognized the need to create a system in which one faulty component wouldn’t affect the entire software system. In early software development, best practice involved tightly coupling all of the software’s components in what is known as a monolithic application. However, monolithic applications require extra effort to respond to changes in the system.

Our application architecture

In this tutorial, we’ll create a chat application in Node.js using the Net node module. This module enables us to establish a client-server TCP connection, allowing applications to communicate and share data securely. Node is still called single-threaded even though there are several background threads since a single thread handles all requests. Internal management by Node controls how async processes are executed on the background threads. Because Node ensures it, these Async Tasks are Event Based and Asynchronous.

When the application gets scaled, the need for global variables that can be accessed by every module arises. We can separate all the global variables in one file in the config folder. Node.js is blessed with a large community of developers supporting it. NPM, the Node package manager, is a package manager that can be used to install all the third-party modules in Node.js easily. Making use of all these makes development very easy, and developers can focus on the logic part more.

Working with fs Module in Node Js

NodeJS uses the “Single Threaded Event Loop” architecture to handle multiple concurrent client requests. When a request comes to the Node server it works like an event-driven processing model of javascript with a callback mechanism. A single thread from the thread pool is assigned to a single complex request. This thread will be responsible to complete that particular blocking operation by using external resources such as compute, database, file system, etc. Once the task will complete it will pass the response to the event loop then the event loop will send the response to the client. A Node.js application usually needs to connect to other backends, third-party services, or databases to retrieve and write data.

We must build an event-based access layer architecture to prevent the Main Thread from waiting for the Asynchronous Request to complete. While the expensive I/O request is being processed, the Main Thread can switch to another task. An event is fired, indicating that the time-consuming activity has been completed and that the main thread can continue processing the request. All the threads available for doing certain boring and error-prone tasks necessary to satisfy client requests are collected in a thread pool. Incoming client requests are stored by the js server and sent one at a development time into the Event Loop.

Error handling and logging

Whenever we have to transfer files, large files may create a problem. Gzip is a lossless compression mechanism that can compress files so that they can be transferred quickly. You can compress the multimedia files that are served on the web pages to reduce the load and make processing faster. The division of code into various modules helps in making debugging and testing easy.

The event-driven architecture of Node.js makes it a perfect choice for microservices, being fast, highly scalable, and easy to maintain. We then created an instance of Express and invoked the Express router function. Using the Express instance, we created our first route that sends a response to the client when a request hits the server. To achieve effective performance, there has to be a means of communication between the microservices.

Controlled access to content

This approach ensures stability and configurational consistency across the application. If the code of a class, function, or file becomes excessively lengthy, consider splitting it into smaller modules wherever possible and bundle them within related folders. This approach helps in grouping related files together and is essential for enhancing code modularity and organization. When initialized through the Sequelize() constructor, the library creates a pool of database connections.

Server:

Because the tests are performed at the time of development, bugs can be caught sooner, reducing the time-consuming process of debugging. The view‘s primary responsibility is to present the data to the user and handle UI components. It receives data from the Model via controllers and renders it for the user to interact. The acquire property in the pool object specifies the maximum time in milliseconds that Sequelize will try to get a connection before throwing a ConnectionAcquireTimeoutError. In the above example, the pool will wait up to 120 seconds before running each query or transaction. Its extensive API allows you to abstract the database layer, whether the DMBS is Oracle, Postgres, MySQL, MariaDB, SQLite, or SQL Server.

Releases 1.x through 3.x were called “io.js” as they were part of the io.js fork. As of Node.js 4.0.0 the former…

Let’s imagine a situation where a single network request must access data from the database, access information from files, and seek information specific to a particular system before responding. Microservices became necessary due to the shortcomings of the monolithic pattern of software development. In a microservice, each software application feature is separated from the other, in most cases with their respective servers and databases. Applications built with this kind of architecture are loosely coupled, also referred to as distributed applications. Node.js uses the “Single Threaded Event Loop” architecture to handle multiple concurrent clients. Node.js Processing Model is based on the JavaScript event-based model along with the JavaScript callback mechanism.

Software development