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TypeScript And “Any” Type

TypeScript is a strongly typed programming language that builds on JavaScript, giving you a better ability to detect errors and describe your code. But sometimes you don't know the exact type of value that you're using because it comes from user input or a third-party API. In this case, you want to skip the type checking and allow the value to pass through the compile check. The TypeScript any type is the perfect solution for you because if you use it, the TypeScript compiler will not complain about the type issue. This blog will help you understand the any type in TypeScript, but before doing that, let's begin with some basic concepts! What is TypeScript? TypeScript checks a program for errors before execution and does so based on the kinds of values; it’s a static type checker. Superset of JavaScript TypeScript is a language that is a superset of JavaScript: JS syntax is, therefore, legal TS. However, TypeScript is a typed superset that adds rules about how different kinds of values can be used. Runtime Behavior TypeScript is also a programming language that preserves JavaScript's runtime behavior. This means that if you move code from JavaScript to TypeScript, it is guaranteed to run the same way, even if TypeScript thinks the code has type errors. Erased Types Roughly speaking, once TypeScript’s compiler is done with checking your code, it erases the types to produce the resulting compiled code. This means that once your code is compiled, the resulting plain JS code has no type information. An easy way of understanding TypeScript A languageA superset of JavaScriptPreserver the runtime behavior of JavaScriptType checker layer JavaScript + Types = TypeScript Basic typing Type annotations TypeScript uses type annotations to explicitly specify types for identifiers such as variables, functions, objects, etc. // Syntax : type Once an identifier is annotated with a type, it can be used as that type only. If the identifier is used as a different type, the TypeScript compiler will issue an error. let counter: number; counter = 1; counter = 'Hello'; // Error: Type '"Hello"' is not assignable to type 'number'. The following shows other examples of type annotations: let name: string = 'John'; let age: number = 25; let active: boolean = true; // Array let names: string[] = ['John', 'Jane', 'Peter', 'David', 'Mary']; // Object let person: { name: string; age: number }; person = { name: 'John', age: 25 }; // Valid // Function let sayHello : (name: string) => string; sayHello = (name: string) => { return `Hello ${name}`; }; Type inference Type inference describes where and how TypeScript infers types when you don’t explicitly annotate them. For example: // Annotations let counter: number; // Inference: TypeScript will infer the type the `counter` to be `number` let counter = 1; Likewise, when you assign a function parameter a value, TypeScript infers the type of the parameter to the type of the default value. For example: // TypeScript infers type of the `max` parameter to be `number` const setCounter = (max = 100) => { // ... } Similarly, TypeScript infers the return type to the type of the return value: const increment = (counter: number) => { return counter++; } // It is the same as: const increment = (counter: number) : number => { return counter++; } The following shows other examples of type inference: const items = [0, 1, null, 'Hi']; // (number | string)[] const mixArr = [new Date(), new RegExp('\d+')]; // (RegExp | Date)[] const increase = (counter: number, max = 100) => { return counter++; }; // (counter: number, max?: number) => number Contextual typing TypeScript uses the locations of variables to infer their types. This mechanism is known as contextual typing. For example: document.addEventListener('click', (event) => { console.log(event.button); // Valid }); In this example, TypeScript knows that the event the parameter is an instance of MouseEvent because of the click event. However, when you change the click event to the scroll the event, TypeScript will issue an error: document.addEventListener('scroll', (event) => { console.log(event.button); // Compile error }); // Property 'button' does not exist on type 'Event'. TypeScript knows that the event in this case, is an instance of UIEvent, not a MouseEvent. And UIEvent does not have the button property, therefore, TypeScript throws an error. Other examples of contextual typing // Array members const names = ['John', 'Jane', 'Peter', 'David', 'Mary']; // string[] names.map(name => name.toUpperCase()); // (name: string) => string // Type assertions const myCanvas = document.getElementById('main-canvas') as HTMLCanvasElement; Type inference vs Type annotations Type inferenceType annotationsTypeScript guesses the typeYou explicitly tell TypeScript the type What exactly is TypeScript any? When you don’t explicitly annotate and TypeScript can't infer exactly the type, that means you declare a variable without specifying a type, TypeScript assumes that you use the any type. This practice is called implicit typing. For example: let result; // Variable 'result' implicitly has an 'any' type. So, what exactly is any? TypeScript any is a particular type that you can use whenever you don't want a particular value to cause type-checking errors. That means the TypeScript compiler doesn't complain or issue any errors. When a value is of type any, you can access any properties of it, call it like a function, assign it to (or from) a value of any type, or pretty much anything else that’s syntactically legal: let obj: any = { x: 0 }; // None of the following lines of code will throw compiler errors. // Using `any` disables all further type checking, and it is assumed // you know the environment better than TypeScript. obj.foo(); obj(); obj.bar = 100; obj = 'hello'; const n: number = obj; Looking back at an easier-to-understand any: A special type.Skip/Disable type-checking.TypeScript doesn't complain or issue any errors.Default implicit typing is any. Note that to disable implicit typing to the any type, you change the noImplicitAny option in the tsconfig.json file to true. Why does TypeScript provide any type? As described above, while TypeScript is a type checker, any type tells TypeScript to skip/disable type-checking. Whether TypeScript has made a mistake here and why it provides any type? In fact, sometimes the developer can't determine the type of value or can't determine the return value from the 3rd party. In most cases they use any type or implicit typing as any. So they seem to think that TypeScript provides any to do those things. So, is that the root reason that TypeScript provides any? Actually, I think there is a more compelling reason for TypeScript providing any that the any type provides you with a way to work with the existing JavaScript codebase. It allows you to gradually opt-in and opt out of type checking during compilation. Therefore, you can use the any type for migrating a JavaScript project over to TypeScript. Conclusion TypeScript is a Type checker layer. The TypeScript any type allows you to store a value of any type. It instructs the compiler to skip type-checking. Use the any type to store a value when you migrate a JavaScript project over to a TypeScript project. In the next blog, I will show you more about the harmful effects of any and how to avoid them. Hope you like it! See you in the next blog! Reference TypeScript handbookTypeScript tutorial Author: Anh Nguyen

A Better Way To Use Services In React Application

Sometimes you have/want to create and use a service in your application for the DRY principle. But do you know exactly what is a service? And what is the best way to use services in React applications? Hi everyone! It's nice to meet you again in React related series. In the previous article, we discussed about effective state management in React, we learned about Context: what is it? when to use it? One of the use cases is using a context to share a collection of services through the components tree, but what kind of things can be called a service? And how is it integrated into React application? Let's discover the following sections: What is a Service? Service is just a group of helper functions that handle something particularly and can be reused across application, for example: Authentication Service that includes authentication status checking, signing in, signing out, getting user info …Http Service that handles request header, request method, request body … How to use? There are different kinds of implementation and usage, I just provide my favorite one that follows Angular module/services provider concepts. Create a service A service is a JavaScript regular class, nothing related to React. export default class ApiService { constructor() {} _setInterceptors() {} _handleResponse_() {} _handleError_() {} get() {} post() {} put() {} delete() {} } export default class AuthService { constructor() {} isAuthenticated() {} getUserInfo() {} signIn() {} signOut() {} } Create a Context Create a context with provider and pass services as props. import { createContext, useState } from 'react'; import { ApiService, AuthService } from '@services'; const services = { apiService: new ApiService(), authService: new AuthService() }; const AppContext = createContext(); const { Provider } = AppContext; const AppProvider = ({ children }) => { return <Provider value={{ services }}>{children}</Provider>; }; export { AppContext, AppProvider } Use a context Place a context provider at an appropriate scope, all consumers should be wrapped in it. import { AppProvider } from './context/AppContext'; import ComponentA from './components/ComponentA' const App = () => { return ( <AppProvider> <div className="app"> <ComponentA /> </div> </AppProvider> ); }; export default App; Inside a child component, use React hooks useContext to access services as a context value. import { useContext, useEffect } from 'react'; import { AppContext } from '../context/AppContext'; const ChildComponent = () => { const { services: { apiService, authService } } = useContext(AppContext); useEffect(() => { if (authService.isAuthenticated()) { apiService.get(); } }, []); return <></>; } export default ComponentA; Above are simple steps to integrate services with context. But it would be complicated in the actual work. Consider organizing context with approriate level/scope. My recommendation is to have two kinds of service contexts in your application: App Services Context to put all singleton services. Bootstrap it once at root, so only one instance for each is created while having them shared over the component tree.For others, create separate contexts and use them anywhere you want and whenever you need. Alternatives Service is not the only one way to deal with reusable code, it depends on what you intend to do, highly recommend to: Use a custom hook, if you want to do reusable logic and hook into a state.Use a Higher-order component, if you want to do the same logic and then render UI differently. Reference Does React Context replace React Redux?React RetiX - another approach to state management Author: Vi Nguyen

Does React Context Replace React Redux?

Table of contents What is Context?How and when to use a Context?When to use Redux?Does Context replace Redux? context-or-redux-1024x768 As you all know, nowadays, React has become one of the most famous JavaScript libraries in the world. It's easy to learn and use. It comes with a good supply of documentation, tutorials, and training resources. Any developer who comes from a JavaScript background can easily understand and start creating web apps using React in a few days with the main concepts: JSXRendering ElementsComponents and PropsState and LifecycleHandling Events But to become an expert in React, it would take more time. You have to deep dive into advanced things: Higher-Order componentsContextCode-SplittingAvoiding unexpected rerenderEspecially, Effective state management When it comes to state management in React applications, we instantly think about React Redux. This is a favorite and widespread tool across developer's communities and applications. Recently, a lot of questions have come to us about using React Context as an alternative for React Redux. To answer those questions, have a brief of React Context first. What is the context? The context was originally introduced for passing props through the component tree, but since newer versions, React provided the powerful feature that allows updating context from a nested component. Meanwhile, Context can now be a state management tool. Let's see how easy it works? Context with Hooks There are many ways to integrate Context, in this article, I just demo the simplest one Create a context import { createContext } from 'react'; export const ThemeContext = createContext(defaultTheme); So simple, createContext is the built-in function that allows you to create a context with default value. Create a provider A provider allow consuming components to subscribe to context changes const { Provider } = ThemeContext; const ThemeProvider = ( { children } ) => { const theme = { ... }; return <Provider value={{ theme }}>{children}</Provider>; }; Create a consumer The simplest way to subscribe to the context value is to use the useContext hook. export const ThemeInfo = () => { const { theme } = useContext(ThemeContext); return ( <div>backgroundColor: {theme?.background}</div> ); } A consumer must be wrapped inside a Provider if not it would not be noticed and then re-render when context data changes. <App> <ThemeProvider> <ThemeInfo></ThemeInfo> </ThemeProvider> </App> Update the context from a consumer It is sometimes necessary to update the context from consumers, context itself doesn't provide any method to do that, but together with hooks, it can be easy: Use useState to manage context valuesetTime is passed as a callback const { Provider } = ThemeContext; const ThemeProvider = ( { children } ) => { const [theme, setTheme] = useState(defaultTheme); return <Provider value={{ theme, setTheme }}>{children}</Provider>; }; From a consuming component, we can update the context value by executing the callback provided by context export const ButtonChangeTheme = () => { const { setTheme } = useContext(ThemeContext); return ( <button onClick={() => setTheme(newTheme)}>Change</button> ); } Again, don't forget to wrap ButtonChangeTheme consumer inside ThemeProvider <App> <ThemeProvider> <ButtonChangeTheme></ButtonChangeTheme> </ThemeProvider> </App> When to use context? As official guideline Context is designed to share data that can be considered global for a tree of React components. Below are common examples of data that Context can cover: Application configurationsUser settingsAuthenticated userA collection of services How to use context in a better way? As mentioned before, when the context value changes, all consumers that use the context will be immediately re-rendered. So putting it all into one context is not a good decision. Instead, create multi-contexts for different kinds of data. EX: one context for Application configurations, one for Authenticated user and others.Besides separating unrelated contexts, using each in its proper place in the component tree is equally significant.Integrate context adds complexity to our app by creating, providing, and consuming the context, so drilling props through 2-3 levels in a tree component is not a problem(Recommended to use instead of context)Restrictively apply context for high-frequency data updated, because context is not designed for that.​ What about React Redux? Unlike Context, React Redux is mainly designed for state management purposes, and covers it well. However, take a look at some highlights from Redux team: Not all apps need Redux. It's important to understand the kind of application you're building, the kinds of problems that you need to solve, and what tools can best solve the problems you're facing. You'll know when you need Flux. If you aren't sure if you need it, you don't need it. Don't use Redux until you have problems with vanilla React. Those recommendations clearly answer the question: When to use Redux? Conclusion So, Does React Context replace React Redux? The short answer is no, it doesn’t. React Redux and React Context can be used together instead of as alternatives. But how to use them together? It depends. If you understand the main concepts for each: React Context is designed for props drilling, it also has ways to update context data, but is recommended to deal with the simple follow of data changes.Redux is built for state management, especially for the frequently updated states used at many places in the application. Based on that you can easily decide what should be implemented in your application. In the end, try to use Context first, if something is not covered by Context, it's time to use Redux. Enjoy coding! Reference Context official docsRedux FAQ: generalIf you are not interested in using Redux, you can check out React RetiX for a different approach to state management.I can not remember all the sources I have read, but it helps a lot in having comparison between Context and Redux. Thank you and sorry for not listing them all in this article!​ Author: Vi Nguyen

OTTclouds Wins Sao Khue Award 2025 – A Proud Moment for SupremeTech

We’re thrilled to share an exciting milestone in SupremeTech’s journey! Our flagship product, OTTclouds, has officially been honored with the Sao Khue Award 2025, one of Vietnam’s most prestigious awards in the software and IT industry.  This recognition marks a proud moment for our entire team and highlights the innovation, dedication, and impact behind OTTclouds — our all-in-one cloud-based platform for OTT, FAST channel, and VOD streaming. As we celebrate this achievement, we’re also looking ahead to new opportunities to expand our reach and support the digital transformation of the media industry both in Vietnam and around the world. SupremeTech – Building Innovative Digital Solutions SupremeTech is a software company based in Da Nang, Vietnam, delivering tailor-made digital solutions to clients worldwide. Our team excels in a wide range of services, including web and mobile application development, AI and data engineering, cloud infrastructure and DevOps, quality assurance and software testing, as well as providing dedicated development teams for long-term collaboration. One of our primary products is OTTclouds – a comprehensive solution for streaming video content over the internet. This platform has enabled media companies to launch services quickly and scale efficiently. And now, OTTclouds has been honored with one of the most respected tech awards in Vietnam. What is OTTclouds? OTTclouds is an all-in-one FAST channel and OTT streaming solution that helps businesses deliver video content online. It includes services for: Streaming FAST channels (Free Ad-Supported TV)Video on Demand (VOD)Content management system (CMS)User and subscription managementAdvertising integrationCross-device support (Smart TVs, mobile apps, web)Analytics to track viewer behavior and platform performance OTTclouds helps content owners reduce costs, speed up time-to-market, and scale their services easily. It’s ideal for media companies seeking to deliver high-quality streaming without incurring the expense of building expensive infrastructure. From Global Projects to the Local Market Since its launch, OTTclouds has been utilized in numerous international projects, enabling media businesses to deliver content to audiences worldwide. Our platform helps clients: Save money on servers and hardware.Launch new streaming services faster.Reach users across many platforms.Grow their systems in tandem with their audience's growth. Now, we’re ready to bring OTTclouds to more businesses in Vietnam. As the demand for online content continues to rise, local broadcasters, publishers, and content creators are seeking new ways to engage with their viewers. OTTclouds is here to help them do that with a modern, flexible, and easy-to-use solution. Why the Sao Khue Award Matters Winning the Sao Khue Award 2025 is a proud and meaningful achievement for both OTTclouds and the entire SupremeTech team. More than just a prestigious award, this recognition is a clear validation that our hard work is creating real impact and value for the media and broadcasting industry. Presented by VINASA (Vietnam Software and IT Services Association), the Sao Khue Award is one of the highest honors in Vietnam’s technology sector. Each year, it highlights the most innovative and high-performing software products in the country, and OTTclouds was selected in the category of New Software Products and Solutions for its flexibility, scalability, and practical benefits to the media industry. This milestone reinforces our commitment to developing future-ready, cloud-based solutions that meet the evolving needs of content providers. It also provides us with a strong foundation to build greater trust with new clients, expand our presence in Vietnam and Southeast Asia, and continue to improve our product to serve a wider network of partners. We are deeply grateful to the judging committee for this recognition and sincerely thank all our clients and partners who have supported and believed in us along the way. Ready to Build Your Streaming Platform? If you’re looking to launch an OTT or FAST channel service or want to enhance your current video streaming system, OTTclouds is ready to support you. Learn more about OTT Streaming Solution and contact us for a demo or consultation. Let’s build the future of digital broadcasting — together.