Implementing file uploads with Redux Toolkit

29 Sep 2023

In modern web applications, file uploads are a common feature that allows users to upload files to the server. In this blog post, we will explore how to implement file uploads using Redux Toolkit, a popular library for managing state in React applications.

Setting up Redux Toolkit

To get started, make sure you have a React application set up with Redux Toolkit. If you haven’t done that yet, you can follow the Redux Toolkit documentation to set up your project.

Handling File Uploads

Define the Initial State

In your Redux slice file, define the initial state for your file upload feature.

import { createSlice } from '@reduxjs/toolkit';

const initialState = {
  isLoading: false,
  progress: 0,
  error: null,
  file: null,
};

const fileUploadSlice = createSlice({
  name: 'fileUpload',
  initialState,
  // ... reducers and actions
});

Create Actions and Reducers

Next, create actions and reducers to handle the different stages of the file upload process.

const fileUploadSlice = createSlice({
  name: 'fileUpload',
  initialState,
  reducers: {
    startLoading: (state) => {
      state.isLoading = true;
    },
    setProgress: (state, action) => {
      state.progress = action.payload;
    },
    setError: (state, action) => {
      state.error = action.payload;
      state.isLoading = false;
    },
    setFile: (state, action) => {
      state.file = action.payload;
    },
    clearUploadState: (state) => {
      state.isLoading = false;
      state.progress = 0;
      state.error = null;
      state.file = null;
    },
  },
});

Implement the File Upload Functionality

Now, let’s implement the actual file upload functionality. You can use libraries like axios or fetch to make the HTTP request to the server.

export const uploadFile = (file) => async (dispatch) => {
  try {
    dispatch(startLoading());

    // Calculate the file size (optional step)
    const fileSize = file.size;

    // Prepare the file upload data
    const formData = new FormData();
    formData.append('file', file);

    // Make the file upload request
    const response = await axios.post('/api/upload', formData, {
      onUploadProgress: (progressEvent) => {
        const progress = Math.round((progressEvent.loaded * 100) / progressEvent.total);
        dispatch(setProgress(progress));
      },
    });

    // Handle success and update the state
    dispatch(setFile(response.data));
    dispatch(clearUploadState());
  } catch (error) {
    dispatch(setError(error.message));
    dispatch(clearUploadState());
  }
};

Connect Redux State to the React Component

In your React component, connect the Redux state and dispatch actions to handle the file upload.

import { useSelector, useDispatch } from 'react-redux';
import { uploadFile } from '../store/fileUploadSlice';

const FileUploadComponent = () => {
  const { isLoading, progress, error, file } = useSelector((state) => state.fileUpload);
  const dispatch = useDispatch();

  const handleFileUpload = (event) => {
    const selectedFile = event.target.files[0];
    dispatch(uploadFile(selectedFile));
  };

  return (
    <div>
      <input type="file" onChange={handleFileUpload} />
      {isLoading && <div>Loading...</div>}
      {progress !== 0 && <div>Progress: {progress}%</div>}
      {error && <div>Error: {error}</div>}
      {file && <div>File Uploaded: {file}</div>}
    </div>
  );
};

Conclusion

In this blog post, we have learned how to implement file uploads using Redux Toolkit. We defined the initial state, created actions and reducers, implemented the file upload functionality, and connected the Redux state to a React component. File uploads are now made easy with Redux Toolkit, allowing you to efficiently manage the state of your file upload feature in your React application.

#React #ReduxToolkit