10 Angular State Management Best Practices
State management in Angular can be a difficult task, but there are some best practices that can help make it easier. In this article, we'll go over 10 of them.
Angular is a popular JavaScript framework used to create web applications. It is a powerful tool for creating complex, interactive user interfaces. However, managing the state of an application can be a challenge.
In this article, we will discuss 10 best practices for managing state in Angular applications. We will look at how to use the Angular Router, how to use the NgRx library, and how to use the Redux pattern. We will also discuss how to use the Angular CLI to create a state management system. By following these best practices, you can ensure that your Angular application is well-structured and easy to maintain.
1. Use the Redux pattern
Redux is a predictable state container for JavaScript applications that helps you write applications that behave consistently, run in different environments (client, server, and native), and are easy to test.
Redux also provides a single source of truth for your application’s state, which makes it easier to debug and maintain. It also allows you to easily track changes over time by logging every action taken in the app. Finally, Redux encourages code reuse by allowing developers to create reusable reducers and selectors that can be used across multiple components.
2. Keep your state as simple as possible
When your state is complex, it can be difficult to debug and maintain. It also makes it harder for other developers to understand what’s going on in the application. Keeping your state simple will make it easier to manage and more readable for everyone involved.
To keep your state simple, try to avoid nesting objects or arrays too deeply. Instead, break them up into smaller chunks that are easier to work with. Additionally, use descriptive names for each piece of data so that it’s clear what they represent. Finally, consider using a library like Redux to help you manage your state in an organized way.
3. Avoid storing complex data structures in the store
When you store complex data structures in the store, it can become difficult to keep track of changes and updates. This is because when a change occurs, all parts of the structure must be updated accordingly. If any part of the structure is not updated correctly, then the entire structure may become corrupted or out-of-sync with other parts of the application.
To avoid this problem, try to break down complex data structures into smaller, more manageable pieces that can be stored separately in the store. This will make it easier to update each piece individually without having to worry about the integrity of the entire structure.
4. Prefer immutability
Immutability means that once a value is set, it cannot be changed. This helps to ensure that the state of your application remains consistent and predictable. It also makes debugging easier since you can trace back any changes in the state to their source.
Additionally, immutability allows for better performance since Angular can detect when values have not been changed and skip unnecessary re-rendering. Finally, immutability encourages good coding practices such as avoiding side effects and making sure data is always valid.
5. Don’t modify the state directly
When you modify the state directly, it can lead to unexpected behavior and bugs. This is because when you modify the state directly, you bypass any logic that may be in place for validating or transforming data before it’s stored in the state.
Instead of modifying the state directly, use setters and getters to access and update the state. Setters are functions that allow you to set a value in the state, while getters are functions that allow you to retrieve values from the state. By using these methods, you ensure that all necessary logic is applied to the data before it’s stored in the state.
6. Maintain a normalized state shape
Normalizing your state shape helps to keep the data in a consistent format, which makes it easier to read and update. It also reduces the amount of duplicate data stored in the application, making it more efficient. Finally, normalizing the state shape allows for better scalability as the application grows.
To achieve this, you should use a library like Redux or NgRx to manage your state. These libraries provide tools that help you maintain a normalized state shape by allowing you to store related pieces of data together in one place. This makes it easier to access and modify the data when needed.
7. Use selectors to access parts of the state
Selectors are functions that take the state as an argument and return a specific part of it. This allows you to keep your components decoupled from the state, making them easier to test and maintain.
Selectors also make it easy to access parts of the state without having to manually traverse through the entire object tree. This makes it much faster and more efficient when accessing data in large applications. Finally, selectors can be used to create derived data from the state, which is useful for displaying complex information on the UI.
8. Keep selector logic out of components
When selector logic is placed in components, it can lead to tight coupling between the component and the state. This makes it difficult to reuse the component or make changes to the state without having to modify the component as well. It also increases the complexity of the codebase, making it harder to maintain.
Instead, selector logic should be kept separate from components. This allows for better separation of concerns and more flexibility when making changes. Selectors should be written as pure functions that take the state as an argument and return a value based on the given parameters. This way, components can remain agnostic to the underlying state structure and can be reused with different states.
9. Avoid sharing selectors between multiple modules
Selectors are used to access state from the store, and if multiple modules share selectors, it can lead to unexpected behavior.
For example, if two different modules use the same selector to access a piece of state, then when one module updates that state, the other module will also be affected. This could cause bugs or unexpected results in your application.
To avoid this issue, make sure each module has its own set of selectors that are specific to that module. That way, you can ensure that each module is accessing only the data it needs, and any changes made by one module won’t affect another.
10. Be careful with async side effects
Async side effects can cause unexpected behavior in your application, as they are not always predictable.
For example, if you have an async action that updates a state variable, but the update is delayed due to network latency or other factors, then the UI may not reflect the updated value until after the user has already interacted with it. This could lead to confusion and frustration for users.
To avoid this issue, make sure to use proper techniques such as using observables or promises to ensure that all async actions complete before updating the state variables. Additionally, be sure to test any code involving async operations thoroughly to ensure that everything works as expected.