Javascript

Maximizing Routing Flexibility with Next.js Parallel and Intercepting Routes

Mattia Magi

Published Apr 5, 2024

Updated Apr 5, 2024

3 min read

Maximizing Routing Flexibility with Next.js Parallel and Intercepting Routes

Introduction:

Next.js, a powerful React framework, offers two essential features - Parallel Routes and Intercepting Routes - that enable developers to create highly dynamic and seamless user experiences in their applications. In this blog post, we will explore both Parallel Routes and Intercepting Routes, highlighting their functionalities, use cases, and how they can be combined to enhance application routing.

What are Parallel Routes?

Parallel Routes in Next.js allow the rendering of multiple pages within a shared layout. Rather than navigating to a completely separate page, Parallel Routes enable the simultaneous rendering of different pages based on certain conditions such as user roles or tab navigation. By leveraging named slots, defined using the @folder convention, multiple pages can be seamlessly integrated into a single layout, enhancing user experience and reducing code duplication.

How to Use Parallel Routes:

To utilize Parallel Routes in Next.js, you must define named slots for the desired pages within your application's folder structure. These slots are then passed as props to a shared parent layout component. For example, consider a social networking application where two pages, feed and notifications, must be rendered within a common layout. You can define Parallel Routes using the following structure:

-app
  - @feed
	- page.tsx
  - @notifications
	- page.tsx
- layout.tsx
- page.tsx

The layout component in app/layout.js will accept the @feed and @notifications slots as props and render them alongside the children prop. Here's an example of the layout component:

export default function Layout({
  children,
  feed,
  notifications,
}) {
  return (
    <>
      {children}
      {feed}
      {notifications}
    </>
  )
}

It's important to note that slots do not affect the URL structure and are not considered route segments. This means the URL would be /mypage/@feed/views for a route like /mypage/views since @feed is a slot.

Also, to prevent the application from rendering nothing or throwing an error, we could use the default.tsx file:

-app
  - @feed
	- page.tsx
  - @notifications
	- page.tsx
- layout.tsx
- page.tsx
- default.tsx

In this example, the default.tsx file specifies the default content (or fallback) to render when none of the named slots match the current route. It acts as a catch-all for routes without a corresponding slot.

Some Use Cases:

Conditional Routes: Parallel Routes can conditionally render routes based on certain conditions, such as user roles. For example, you can render a different dashboard page for admins and users. This can be achieved by creating a layout component specific to the dashboard and checking the user role to determine which slot to render.

Tab Groups: You can utilize Parallel Routes to create tabbed navigation within a section. This is especially useful for analytics or multi-page views. Adding a layout inside a slot allows users to navigate between different pages within that slot independently.

Loading and Error UI: Parallel Routes can be independently streamed, allowing you to define custom error and loading states for each route. This enables better control over the user experience by providing distinct feedback for different app sections.

Modals: Parallel Routes can be combined with Intercepting Routes to create modals with shareable URLs, preserved context on refresh, and customized navigation behavior. By intercepting certain routes and rendering them within a modal component, you can create a seamless modal experience.

Understanding Intercepting Routes:

Intercepting Routes in Next.js allows you to load content from another route within the current layout without changing the URL or refreshing the page.

Using the (..) Convention:

Intercepting routes are defined using the (..) convention, which is similar to the relative path convention ../ but for route segments. The convention allows for matching segments on the same level (.), one level above (..), two levels above (..)(..), or from the root app directory (...). For example, to intercept the photo segment from within the feed segment, you can create a (..)photo directory.

Integrating Intercepting Routes with Parallel Routes - Modals:

One powerful use case for Intercepting Routes is creating modals, which can be combined with Parallel Routes to solve common challenges such as making the modal content shareable through a URL, preserving context on page refresh, and handling backward and forward navigation.

Let's make an example:

// Layout Component for gallery
export default function Layout({ children, modal }) {
  return (
    <>
      {children}
      {modal}
    </>
  )
}

// Photo Component inside the (..)photo folder
export default function Photo({ id }) {
  return <Modal><PhotoDetail id={id} /></Modal>
}

// Gallery Page
export default function Gallery() {
  return allPhotos.map((photo) => 
	  <Link href=`/photo/${photo.id}`>
		  <Photo>
	  <Link>
	  )
}

// Photo page inside the photo folder
export default function Photo({ id }) {
  return <PhotoDetail id={id} />
}

Our folder structure will be:

In this example, when a user clicks on a photo within the /gallery page, the route /photo/:photoId will be intercepted and rendered within the (..)photo directory, overlaying the gallery content. This means that the photo route is only one segment level higher despite being two file-system levels higher.

In the example above, the path to the photo segment can use the (..) matcher since @modal is a slot and not a segment.

Common Use Cases - Beyond Modals:

Intercepting Routes can also be utilized in other scenarios. Some examples include opening a login modal in a top navbar while having a dedicated /login page, or opening a shopping cart in a side modal for better accessibility or creating wizards or multi-step forms within a single page. The possibilities are endless.

Conclusion

Next.js Parallel and Intercepting Routes offer powerful methods for enhancing the routing capabilities of your applications. With Parallel Routes, multiple pages can be seamlessly integrated within a shared layout, simplifying navigation and enhancing user experience. By incorporating Intercepting Routes, you can create dynamic overlays like modals, enabling content from different routes to be displayed within the current layout. By leveraging these features, you can unlock exciting possibilities and take your Next.js applications to new heights of user engagement.

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About the author(s)

Mattia Magi

Introduction to Zod for Data Validation

As web developers, we're often working with data from external sources like APIs we don't control or user inputs submitted to our backends. We can't always rely on this data to take the form we expect, and we can encounter unexpected errors when it deviates from expectations. But with the Zod library, we can define what our data ought to look like and parse the incoming data against those defined schemas. This lets us work with that data confidently, or to quickly throw an error when it isn't correct. Why use Zod? TypeScript is great for letting us define the shape of our data in our code. It helps us write more correct code the first time around by warning us if we are doing something we shouldn't. But TypeScript can't do everything for us. For example, we can define a variable as a string or a number, but we can't say "a string that starts with user_id_ and is 20 characters long" or "an integer between 1 and 5". There are limits to how much TypeScript can narrow down our data for us. Also, TypeScript is a tool for us developers. When we compile our code, our types are not available to the vanilla JavaScript. JavaScript can't validate that the data we actually use in our code matches what we thought we'd get when we wrote our TypeScript types unless you're willing to manually write code to perform those checks. This is where we can reach for a tool like Zod. With Zod, we can write data schemas. These schemas, in the simplest scenarios, look very much like TypeScript types. But we can do more with Zod than we can with TypeScript alone. Zod schemas let us create additional rules for data parsing and validation. A 20-character string that starts with user_id_? It's z.string().startsWith('user_id_').length(20). An integer between 1 and 5 inclusive? It's z.number().int().gte(1).lte(5). Zod's primitives give us many extra functions to be more specific about *exactly* what data we expect. Unlike TypeScript, Zod schemas aren't removed on compilation to JavaScript—we still have access to them! If our app receives some data, we can verify that it matches the expected shape by passing it to your Zod schema's parse function. You'll either get back your data in exactly the shape you defined in your schema, or Zod will give you an error to tell you what was wrong. Zod schemas aren't a replacement for TypeScript; rather, they are an excellent complement. Once we've defined our Zod schema, it's simple to derive a TypeScript type from it and to use that type as we normally would. But when we really need to be sure our data conforms to the schema, we can always parse the data with our schema for that extra confidence. Defining Data Schemas Zod schemas are the variables that define our expectations for the shape of our data, validate those expectations, and transform the data if necessary to match our desired shape. It's easy to start with simple schemas, and to add complexity as required. Zod provides different functions that represent data structures and related validation options, which can be combined to create larger schemas. In many cases, you'll probably be building a schema for a data object with properties of some primitive type. For example, here's a schema that would validate a JavaScript object representing an order for a pizza: ` Zod provides a number of primitives for defining schemas that line up with JavaScript primitives: string, number, bigint, boolean, date, symbol, undefined, and null. It also includes primitives void, any, unknown, and never for additional typing information. In addition to basic primitives, Zod can define object, array, and other native data structure schemas, as well as schemas for data structures not natively part of JavaScript like tuple and enum. The documentation contains considerable detail on the available data structures and how to use them. Parsing and Validating Data with Schemas With Zod schemas, you're not only telling your program what data should look like; you're also creating the tools to easily verify that the incoming data matches the schema definitions. This is where Zod really shines, as it greatly simplifies the process of validating data like user inputs or third party API responses. Let's say you're writing a website form to register new users. At a minimum, you'll need to make sure the new user's email address is a valid email address. For a password, we'll ask for something at least 8 characters long and including one letter, one number, and one special character. (Yes, this is not really the best way to write strong passwords; but for the sake of showing off how Zod works, we're going with it.) We'll also ask the user to confirm their password by typing it twice. First, let's create a Zod schema to model these inputs: ` So far, this schema is pretty basic. It's only making sure that whatever the user types as an email is an email, and it's checking that the password is at least 8 characters long. But it is *not* checking if password and confirmPassword match, nor checking for the complexity requirements. Let's enhance our schema to fix that! ` By adding refine with a custom validation function, we have been able to verify that the passwords match. If they don't, parsing will give us an error to let us know that the data was invalid. We can also chain refine functions to add checks for our password complexity rules: ` Here we've chained multiple refine functions. You could alternatively use superRefine, which gives you even more fine grained control. Now that we've built out our schema and added refinements for extra validation, we can parse some user inputs. Let's see two test cases: one that's bound to fail, and one that will succeed. ` There are two main ways we can use our schema to validate our data: parse and safeParse. The main difference is that parse will throw an error if validation fails, while safeParse will return an object with a success property of either true or false, and either a data property with your parsed data or an error property with the details of a ZodError explaining why the parsing failed. In the case of our example data, userInput2 will parse just fine and return the data for you to use. But userInput1 will create a ZodError listing all of the ways it has failed validation. ` ` We can use these error messages to communicate to the user how they need to fix their form inputs if validation fails. Each error in the list describes the validation failure and gives us a human readable message to go with it. You'll notice that the validation errors for checking for a valid email and for checking password length have a lot of details, but we've got three items at the end of the error list that don't really tell us anything useful: just a custom error of Invalid input. The first is from our refine checking if the passwords match, and the second two are from our refine functions checking for password complexity (numbers and special characters). Let's modify our refine functions so that these errors are useful! We'll add our own error parameters to customize the message we get back and the path to the data that failed validation. ` Now, our error messages from failures in refine are informative! You can figure out which form fields aren't validating from the path, and then display the messages next to form fields to let the user know how to remedy the error. ` By giving our refine checks a custom path and message, we can make better use of the returned errors. In this case, we can highlight specific problem form fields for the user and give them the message about what is wrong. Integrating with TypeScript Integrating Zod with TypeScript is very easy. Using z.infer<typeof YourSchema> will allow you to avoid writing extra TypeScript types that merely reflect the intent of your Zod schemas. You can create a type from any Zod schema like so: ` Using a TypeScript type derived from a Zod schema does *not* give you any extra level of data validation at the type level beyond what TypeScript is capable of. If you create a type from z.string.min(3).max(20), the TypeScript type will still just be string. And when compiled to JavaScript, even that will be gone! That's why you still need to use parse/safeParse on incoming data to validate it before proceeding as if it really does match your requirements. A common pattern with inferring types from Zod schemas is to use the same name for both. Because the schema is a variable, there's no name conflict if the type uses the same name. However, I find that this can lead to confusing situations when trying to import one or the other—my personal preference is to name the Zod schema with Schema at the end to make it clear which is which. Conclusion Zod is an excellent tool for easily and confidently asserting that the data you're working with is exactly the sort of data you were expecting. It gives us the ability to assert at runtime that we've got what we wanted, and allows us to then craft strategies to handle what happens if that data is wrong. Combined with the ability to infer TypeScript types from Zod schemas, it lets us write and run more reliable code with greater confidence....

Nov 15, 2024

7 mins

JavaScriptZod

The HTML Dialog Element: Enhancing Accessibility and Ease of Use

The HTML Dialog Element: Enhancing Accessibility and Ease of Use Dialogs are a common component added to applications, whether on the web or in native applications. Traditionally there has not been a standard way of implementing these on the web, resulting in many ad-hoc implementations that don’t act consistently across different web applications. Often, commonly expected features are missing from dialogs due to the complexity of implementing them. However, web browsers now offer a standard dialog element. Why use the dialog element? The native dialog element streamlines the implementation of dialogs, modals, and other kinds of non-modal dialogs. It does this by implementing many of the features needed by dialogs for you that are already baked into the browser. This is helpful as it reduces the burden on the developer when making their applications accessible by ensuring that user expectations concerning interaction are met, and it can also potentially simplify the implementation of dialogs in general. Basic usage Adding a dialog using the new tag can be achieved with just a few lines of code. ` However, adding the dialog alone won’t do anything to the page. It will show up only once you call the .showModal() method against it. ` Then if you want to close it you can call the .close() method on the dialog, or press the escape key to close it, just like most other modals work. Also, note how a backdrop appears that darkens the rest of the page and prevents you from interacting with it. Neat! Accessibility and focus management Correctly handling focus is important when making your web applications accessible to all users. Typically you have to move the current focus to the active dialog when showing them, but with the dialog element that’s done for you. By default, the focus will be set on the first focusable element in the dialog. You can optionally change which element receives focus first by setting the autofocus attribute on the element you want the focus to start on, as seen in the previous example where that attribute was added to the close element. Using the .showModal() method to open the dialog also implicitly adds the dialog ARIA role to the dialog element. This helps screen readers understand that a modal has appeared and the screen so it can act accordingly. Adding forms to dialogs Forms can also be added to dialogs, and there’s even a special method value for them. If you add a element with the method set to dialog then the form will have some different behaviors that differ from the standard get and post form methods. First off, no external HTTP request will be made with this new method. What will happen instead is that when the form gets submitted, the returnValue property on the form element will be set to the value of the submit button in the form. So given this example form: ` The form element with the example-form id will have its returnValue set to Submit. In addition to that, the dialog will close immediately after the submit event is done being handled, though not before automatic form validation is done. If this fails then the invalid event will be emitted. You may have already noticed one caveat to all of this. You might not want the form to close automatically when the submit handler is done running. If you perform an asynchronous request with an API or server you may want to wait for a response and show any errors that occur before dismissing the dialog. In this case, you can call event.preventDefault() in the submit event listener like so: ` Once your desired response comes back from the server, you can close it manually by using the .close() method on the dialog. Enhancing the backdrop The backdrop behind the dialog is a mostly translucent gray background by default. However, that backdrop is fully customizable using the ::backdrop pseudo-element. With it, you can set a background-color to any value you want, including gradients, images, etc. You may also want to make clicking the backdrop dismiss the modal, as this is a commonly implemented feature of them. By default, the <dialog> element doesn’t do this for us. There are a couple of changes that we can make to the dialog to get this working. First, an event listener is needed so that we know when the user clicks away from the dialog. ` Alone this event listener looks strange. It appears to dismiss the dialog whenever the dialog is clicked, not the backdrop. That’s the opposite of what we want to do. Unfortunately, you cannot listen for a click event on the backdrop as it is considered to be part of the dialog itself. Adding this event listener by itself will effectively make clicking anywhere on the page dismiss the dialog. To correct for this we need to wrap the contents of the dialog content with another element that will effectively mask the dialog and receive the click instead. A simple element can do! ` Even this isn’t perfect though as the contents of the div may have elements with margins in them that will push the div down, resulting in clicks close to the edges of the dialog to dismiss it. This can be resolved by adding a couple of styles the the wrapping div that will make the margin stay contained within the wrapper element. The dialog element itself also has some default padding that will exacerbate this issue. ` The wrapping div can be made into an inline-block element to contain the margin, and by moving the padding from the parent dialog to the wrapper, clicks made in the padded portions of the dialog will now interact with the wrapper element instead ensuring it won’t be dismissed. Conclusion Using the dialog element offers significant advantages for creating dialogs and modals by simplifying implementation with reasonable default behavior, enhancing accessibility for users that need assistive technologies such as screen readers by using automatic ARIA role assignment, tailored support for form elements, and flexible styling options....

Oct 25, 2024

4 mins

HTMLJavaScript

Awesome 3D experience with VueJS and TresJS: a beginner's guide

Awesome 3D experience with VueJS and TresJS: a beginner's guide Vue.js developers are renowned for raving about the ease, flexibility, and speed of development their framework offers. Tres.js builds on this love for Vue by becoming the missing piece for seamless 3D integration. As a Vue layer for Three.js, Tres.js allows you to leverage the power of Three.js, a popular 3D library, within the familiar and beloved world of Vue components. This means you can create stunning 3D graphics and animations directly within your Vue applications, all while maintaining the clean and efficient workflow you've come to expect. TresJS is a library specifically designed to make incorporating WebGL (the web's 3D graphics API) into your Vue.js projects a breeze. It boasts several key features that make 3D development with Vue a joy: - Declarative Approach: Build your 3D scenes like you would any other Vue component, leveraging the power and familiarity of Vue's syntax. This makes it intuitive and easy to reason about your 3D elements. - Powered by Vite: Experience blazing-fast development cycles with Vite's Hot Module Replacement (HMR) that keeps your scenes updated in real-time, even as your code changes. - Up-to-date Features: Tres.js stays on top of the latest Three.js releases, ensuring you have immediate access to the newest features and functionality. - Thriving Ecosystem: The Tres.js ecosystem offers many resources to enhance your development experience. This includes: - Cientos: A collection of pre-built components and helpers that extend the capabilities of Tres.js, allowing you to focus on building your scene's functionality rather than reinventing the wheel (https://cientos.tresjs.org/). - TresLeches: A powerful state management solution specifically designed for 3D applications built with Tres.js (https://tresleches.tresjs.org/). You can try TresJS online using their official Playground or on their StackBlitz starter. But now, let's dive into a quick code example to showcase the simplicity of creating a 3D scene with TresJS. Setup First, install the package: npm install @tresjs/core three And then, if you are using Typescript, be sure to install the types: npm install @types/three -D If you are using Vite, now you need to modify your vite.config.ts file in this way to make the template compiler work with the custom renderer: ` Create our Scene Imagine a 3D scene as a virtual stage. To bring this stage to life, we need a few key players working together: 1. Scene: Think of this as the container that holds everything in your 3D world. It acts as the canvas where all the objects, lights, and the camera reside, defining the overall environment. 2. Renderer: This is the magician behind the curtain, responsible for taking all the elements in your scene and translating them into what you see on the screen. It performs the complex calculations needed to transform your 3D scene into 2D pixels displayed on your browser. 3. Camera: Like a real camera, this virtual camera defines the perspective from which you view your scene. You can position and adjust the camera to zoom in, zoom out, or explore different angles within your 3D world. - To make our camera dynamic and allow canvas exploration, we are going to leverage the client's OrbitControls component. Below are our examples. You will see that we just include the component in our canvas, and it just works. 4. Objects: These actors bring your scene to life. They can be anything from simple geometric shapes like spheres and cubes to complex models like characters or buildings. You create the visual elements that tell your story by manipulating and animating these objects. Starting from the beginning: to create our Scene with TresJS we just need to use our component TresCanvas in our Vue component's template: ` The TresCanvas component is going to do some setup work behind the scenes: - It creates a WebGLRenderer that automatically updates every frame. - It sets the render loop to be called on every frame based on the browser refresh rate. Using the window-size property, we force the canvas to take the width and height of our full window. So with TresCanvas component we have created our Renderer and our Scene. Let's move to the Camera: ` We just have to add the TresPerspectiveCamera component to our scene. NOTE: It's important that all scene-related components live between the TresCanvas component. Now, only the main actor is missing, let's add some styles and our object inside the scene. Our Vue component will now look like: ` And our scene will be: A Mesh is a basic scene object in three.js, and it's used to hold the geometry and the material needed to represent a shape in 3D space. As we can see, we can achieve the same with TresJS using the TresMesh component, and between the default slots, we are just passing our object (a Box in our example). One interesting thing to notice is that we don't need to import anything. That's because TresJS automatically generates a Vue Component based on the three objects you want to use in PascalCase with a Tres prefix. Now, if we want to add some color to our object the Three.js Material class comes to help us. We need to add: ` Conclusion Tres.js not only supercharges Vue.js applications with stunning 3D graphics, but it also integrates seamlessly with Nuxt.js, enabling you to harness the performance benefits of server-side rendering (SSR) for your 3D creations. This opens the door to building exceptional web experiences that are both interactive and performant. With Tres.js, Vue.js developers can leverage a declarative approach, cutting-edge features, and a vast ecosystem to bring their immersive web visions to life. If you want to elevate your Vue.js projects with a new dimension, Tres.js is an excellent choice to explore....

Jun 12, 2024

3 mins

Vue3D

Build Facial Recognition and Chatbot AIs using TypeScript with Jack Herrington

In this JS Drop, Danny Thompson is joined by YouTuber Jack Herrington to explore a unique TypeScript and AI project that lets you recognize TV show characters in real time. Just point your camera at a character, and instantly get their details or even chat with them as if they were real! Jack walks through the tech, explaining how client-side face recognition and server-side AI work together to make this possible using the Versal AI library. They discuss prompt engineering, building efficient APIs, and ensuring smooth, interactive AI responses. Jack also shares potential real-world applications, from entertainment to security. Chapters - 0:32 Project Overview – Jack explains the AI-powered character recognition project - 2:17 Setting Up the Project – Overview of how the application is structured and initial setup - 3:04 Client-Side AI – How face detection and character recognition work on the client side - 5:12 Switching to Server Side – Jack demonstrates server-side AI and setting up API endpoints - 8:20 Explaining AI Tooling – How tools and prompts are used to give context to the AI - 10:01 Detailed Prompt Structure – Breaking down the prompt and character context for AI responses - 12:40 Client-Server Interaction – Using the Versal AI library to manage streaming responses - 15:09 Handling Character Data – Training the AI on specific character images and details - 18:15 Practical Use Cases – Discussing potential real-world applications for the face recognition tool - 21:34 Challenges and Lessons Learned – Jack shares obstacles he faced and how he overcame them - 25:45 Building the API – Tips and considerations for creating reliable API endpoints - 28:40 Handling User Inputs – Testing unexpected questions and how the AI responds - 32:00 Using Advanced AI Models – Jack talks about choosing GPT-4 and issues with smaller models - 35:47 Introducing ProNextJS.dev – Jack discusses his new Next.js course, covering advanced topics - 37:20 Closing Thoughts – Danny and Jack wrap up with final thoughts and a link to the GitHub repo Follow Jack Herrington on Social Media Twitter: https://x.com/jherr Linkedin: https://www.linkedin.com/in/jherr/ YouTube: https://www.youtube.com/@jherr Sponsored by This Dot: thisdot.co...

Nov 11, 2024

2 mins

AIArtificial Intelligence

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Maximizing Routing Flexibility with Next.js Parallel and Intercepting Routes

Maximizing Routing Flexibility with Next.js Parallel and Intercepting Routes

Introduction:

What are Parallel Routes?

How to Use Parallel Routes:

Some Use Cases:

Understanding Intercepting Routes:

Using the (..) Convention:

Integrating Intercepting Routes with Parallel Routes - Modals:

Common Use Cases - Beyond Modals:

Conclusion

Mattia Magi

You might also like

Introduction to Zod for Data Validation

The HTML Dialog Element: Enhancing Accessibility and Ease of Use

Awesome 3D experience with VueJS and TresJS: a beginner's guide

Build Facial Recognition and Chatbot AIs using TypeScript with Jack Herrington

Let's innovate together!

You might also like

Introduction to Zod for Data Validation

The HTML Dialog Element: Enhancing Accessibility and Ease of Use

Awesome 3D experience with VueJS and TresJS: a beginner's guide

Build Facial Recognition and Chatbot AIs using TypeScript with Jack Herrington