In-Depth Guide to Single-SPA

1. Introduction

Single-SPA is a JavaScript framework designed to help developers build micro frontend applications. It allows for multiple frameworks to coexist on the same page, enabling better modularity and scalability.

2. What is Single-SPA?

Single-SPA is a framework-agnostic micro frontend library that allows applications built with different frameworks (like React, Vue, Angular, etc.) to be combined into a single application.

3. Key Concepts

• Applications: Independent micro frontends that can be built using different frameworks.
• Parcel: A JavaScript library that helps load applications on demand.
• Router: A mechanism to handle routing at the micro frontend level.

4. Installation

To install Single-SPA, you can use npm or yarn:

npm install single-spa

yarn add single-spa

5. Creating a Simple App

Here’s a simple example of creating a micro frontend application using Single-SPA:

import { registerApplication, start } from 'single-spa';

            registerApplication(
              'app1',
              () => import('./app1/app.js'),
              location => location.pathname.startsWith('/app1')
            );

            registerApplication(
              'app2',
              () => import('./app2/app.js'),
              location => location.pathname.startsWith('/app2')
            );

            start();

In the code above, we register two applications: app1 and app2, which will be loaded based on the current URL path.

6. Best Practices

• Keep micro frontends independent and self-contained.
• Use shared libraries cautiously to avoid version conflicts.
• Implement proper error handling and fallbacks.

7. FAQ

Step-by-Step Flowchart

graph TD;
            A[Start] --> B{Choose Framework};
            B -->|React| C[Build React App];
            B -->|Vue| D[Build Vue App];
            B -->|Angular| E[Build Angular App];
            C --> F[Integrate with Single-SPA];
            D --> F;
            E --> F;
            F --> G[Deploy Application];