Deep integration of TypeScript

The deep integration of TypeScript with Vue.js provides front-end development with type safety and an enhanced development experience. From basic configuration to advanced patterns, this integration significantly improves code quality and maintainability. Basic configuration includes installing necessary dependencies and creating a tsconfig.json file. Single-file components support TypeScript via the `lang="ts"` attribute. The Composition API works particularly well with TypeScript, allowing clear definition of interfaces and types. Props type definitions ensure components receive the correct data types. Custom type declarations extend Vue's global properties, while integration with Vuex/Pinia provides typed state management. Type-safe routing is achieved by extending RouteMeta for enhanced type checking. Advanced type patterns leverage conditional types and type inference for protection. Type applications in testing ensure type safety for component tests. Performance optimizations reduce runtime checks through enums and literal types. Third-party library integration adds type support via declaration files. Type utilities assist in creating reusable type templates. Template type checking is implemented through the Volar extension, enabling type-driven development. Designing components begins with type definitions, while complex state management uses typed state machines to ensure safe state transitions.

Persistent storage solution

In Vue.js applications, common local persistent storage solutions include localStorage and sessionStorage, both of which are based on the Web Storage API and provide a key-value storage mechanism. localStorage data is permanently saved with a capacity of about 5MB, while sessionStorage is only valid for the current session and is cleared when the tab is closed. For large amounts of structured data, IndexedDB is more powerful, supporting transactional operations and indexed queries with a larger storage capacity. Vuex state management can achieve persistence using the vuex-persistedstate plugin. Cookies are suitable for small data storage and are carried with every request. The File System Access API is suitable for handling user files. Sensitive data should be stored encrypted. Different scenarios call for appropriate solutions, such as using localStorage for user preferences, sessionStorage for shopping carts, and IndexedDB for large-scale data. Performance optimizations include batch operations and using Web Workers for processing. Cross-tab communication can leverage the storage event. It is also important to handle storage space limitations.

Server-side rendering supports this.

Server-Side Rendering (SSR) is a technique where Vue components are rendered into HTML strings on the server and sent directly to the browser. Compared to Client-Side Rendering (CSR), it offers better SEO and faster initial page load advantages. Vue SSR is implemented using `vue-server-renderer` and Node.js, with core processes including creating a Vue instance factory function and using the renderer to generate HTML. The Nuxt.js framework simplifies SSR configuration by providing a convention-over-configuration development experience. Client-side hydration is the key process where the browser takes over static HTML to transform it into a dynamic application. Data prefetching strategies include component-level prefetching and Vuex store prefetching. Performance optimizations involve component caching, code splitting, and streaming rendering. Common issues include environment variable checks and memory leak handling. Deployment can be done using PM2, while monitoring focuses on performance metrics and error tracking.

Development of Pinia plugins

Pinia plugins are powerful tools for extending Pinia's functionality, allowing developers to inject custom logic during a store's lifecycle. Essentially, a plugin is a function that receives a context object, providing access to the store instance and the app instance. Core APIs include listening to action calls and state changes, as well as various methods for modifying state. Common plugin use cases include state persistence, multi-tab synchronization, and request caching. Plugins can leverage Vue's dependency injection mechanism to share functionality. TypeScript support enhances the development experience, and multiple plugins can be combined, executing in the order they are registered. Robust plugins should include error handling mechanisms, and performance optimization is also crucial. Plugins differ fundamentally from middleware. Testing strategies ensure plugin quality, and finally, plugins can be published to npm for sharing with other developers.

Inter-store mutual calls

In a Vue.js application, sharing data between multiple stores can be achieved through Vuex modularization, where each module maintains its own state, mutations, actions, and getters. Modules can directly access the rootState or trigger actions in other modules via dispatch to maintain decoupling. Getters can combine states from multiple modules to create derived states. For complex business logic, coordinating actions can be created to handle cross-module workflows. Dynamically registered modules can also participate in interactions, but lifecycle and circular dependencies must be addressed, potentially requiring refactoring or introducing intermediate states. During testing, relevant modules should be mocked to verify correct calls. Frequent cross-module calls may impact performance, which can be optimized by batching operations or caching getters. In large projects, domain-driven design can be used to organize modules with clear boundaries. Compared to Pinia, the interaction methods differ. For debugging, Vue DevTools can be used to observe call relationships, and logging can be added for assistance. Common issues include namespace conflicts and asynchronous state dependencies, which must be handled properly.

Options-style Store writing

The Options-style Store is the traditional state management approach in Vuex, organizing the store by defining an object that includes options such as state, mutations, actions, etc. It is suitable for small to medium-sized projects or beginners. The basic structure consists of state (storing state data), getters (as computed properties), mutations (synchronously modifying state), actions (handling asynchronous operations), and modularization (modules). State centrally manages shared data. Mutations directly modify the state and must be synchronous functions. Actions handle asynchronous tasks and eventually commit mutations to modify the state. Getters derive state, making them suitable for computed properties. Modularization organizes large-scale applications. Strict mode prevents direct state modifications. Plugins extend functionality, such as adding persistence. Components use mapHelpers to simplify access. Handling two-way binding for forms, writing testable code, and TypeScript support for type hints are also covered. Performance optimization techniques and common design patterns, such as state grouping and factory functions for creating modules, are included.

Composition-style Store writing

A composable Store is a way to manage state in Vue 3 using the Composition API. It leverages reactive APIs like `ref` and `reactive` to create reusable state logic, offering greater flexibility and modularity compared to the traditional Options API. The state and logic can be defined in separate files and then imported into components for use, supporting state sharing, complex state management, and asynchronous operations. For states requiring persistence, `localStorage` can be integrated. As the application scales, Stores can be split by functional modules. TypeScript provides better type support for enhanced development. For performance optimization, `shallowRef` can be used to reduce reactive overhead. Composable Stores are suitable for small to medium-sized applications or local state management in larger applications, such as form handling or UI state management. Compared to Pinia, they are more lightweight but offer fewer features.

Create and use a Store

Vuex is the officially recommended state management library for Vue.js, suitable for data sharing and reactive updates in complex applications. First, you need to install Vuex and create a Store instance, which includes core concepts such as state, mutations, actions, and getters. State serves as the data source, mutations are used for synchronous state changes, actions handle asynchronous operations, and getters are equivalent to computed properties. In large-scale applications, the Store can be organized modularly. In Vue 3's Composition API, you can use `useStore` to access the Store. A shopping cart example demonstrates a practical application scenario, and plugins can be developed to extend functionality. Strict mode aids in development and debugging. Finally, it explains how to test mutations and actions to ensure code quality.

Core concepts of Pinia (store/state/getters/actions)

Pinia is Vue.js's lightweight state management library, with core concepts including Store, State, Getters, and Actions. Stores are created using `defineStore` and support both the Options API and Composition API styles. State serves as the reactive data source and can be modified directly, updated in batches via `patch`, replaced entirely, or altered through Actions. Getters function like computed properties, supporting caching and parameter passing. Actions handle synchronous and asynchronous operations without requiring `dispatch` calls. Advanced features include state change subscriptions, plugin extensions, and server-side rendering. Performance optimization recommendations include avoiding expensive computations, using `patch` for batch updates, and splitting stores by functionality. These characteristics make Pinia an ideal choice for state management in Vue applications.

Comparison between Pinia and Vuex

Both Pinia and Vuex are state management libraries for Vue.js, but they differ in design philosophy. Vuex adopts a strict unidirectional data flow, making it suitable for complex applications, while Pinia simplifies the API by removing the mutations concept, aligning better with Vue 3. Pinia outperforms Vuex in TypeScript support, bundle size, performance, and developer experience, offering automatic type inference and a more concise Composition API style. Both support modularity and SSR, but Pinia handles them more simply. Vuex has a more mature plugin ecosystem, whereas Pinia's plugin system is more flexible. Migrating to Pinia requires rewriting mutations and adjusting module structures. For new projects, Pinia is recommended, while existing stable projects need not be forcibly migrated. Debugging tools support both well. Pinia's reactivity system is based on Vue 3's reactive, making operations more intuitive.