Guide to Integrating Image Upload in CKEditor with Spring Boot

CKEditor is a popular WYSIWYG text editor that provides a user-friendly interface for creating and editing rich text content. One of its powerful features is the ability to upload images directly into the editor. In this guide, we will walk through the process of integrating image upload functionality in CKEditor with a Spring Boot backend. By the end of this guide, you’ll have a fully functional setup allowing users to upload images seamlessly through CKEditor, with the images stored in Amazon S3.

0. Prerequisites:

• Basic knowledge of HTML, JavaScript, and Java.
• Familiarity with CKEditor and Spring Boot.

1. Design API to upload image to S3

To upload images from CKEditor to Amazon S3 through a Spring Boot API, you’ll need to set up your backend to handle the file upload requests from CKEditor and then forward those requests to Amazon S3 after handling any necessary authentication and authorization. Here’s a general outline of how you can achieve this:

1. Set up an API endpoint in your Spring Boot application: This endpoint will receive the image upload requests from CKEditor.
2. Handle the image upload request: Parse the incoming request to extract the image file and any additional metadata. Ensure that the necessary security checks are performed to prevent unauthorized uploads.
3. Configure Amazon S3 client: Use the AWS SDK for Java to interact with Amazon S3. Configure the S3 client with your AWS credentials (access key and secret key).
4. Upload the image to Amazon S3: Use the configured S3 client to upload the image file to your desired S3 bucket.
5. Return the URL of the uploaded image: Once the image is successfully uploaded to S3, return the URL of the uploaded image to CKEditor.

Here’s a basic example of how you might implement these steps in your Spring Boot application:

@RestController
public class ImageUploadController {

    @Autowired
    private AmazonS3 amazonS3;

    @Value("${aws.s3.bucket}")
    private String bucketName;

    @PostMapping("/uploadImage")
    public ResponseEntity<String> uploadImage(@RequestParam("file") MultipartFile file) {
        try {
            // Upload file to S3
            String fileName = file.getOriginalFilename();
            amazonS3.putObject(new PutObjectRequest(bucketName, fileName, file.getInputStream(), new ObjectMetadata()));

            // Generate URL for uploaded file
            String imageUrl = amazonS3.getUrl(bucketName, fileName).toString();

            // Return the URL to CKEditor
            return ResponseEntity.ok(imageUrl);
        } catch (IOException e) {
            e.printStackTrace();
            return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR).body("Failed to upload image");
        }
    }
}

In this example:

• ImageUploadController is a Spring MVC controller responsible for handling image upload requests.
• The uploadImage method receives a multipart file containing the image data.
• The image file is uploaded to Amazon S3 using the amazonS3 client.
• After successful upload, the URL of the uploaded image is generated using amazonS3.getUrl() and returned to CKEditor.

Ensure you have the AWS SDK for Java dependency in your pom.xml:

<dependency>
    <groupId>com.amazonaws</groupId>
    <artifactId>aws-java-sdk-s3</artifactId>
    <version>1.11.1033</version> <!-- Use the latest version -->
</dependency>

Also, ensure that you have configured your AWS credentials (access key and secret key) and the S3 bucket name in your application.properties or application.yml file.

This example provides a basic implementation. Depending on your requirements and security considerations, you may need to add additional features such as authentication, authorization, error handling, and validation.

2. Setting up CKEditor

First, include CKEditor in your HTML page. You can do this by adding the following script tag to your HTML file:

<script src="https://cdn.ckeditor.com/4.16.2/standard/ckeditor.js"></script>

Next, create a textarea element where CKEditor will be initialized:

<textarea id="editor"></textarea>

In the CKEditor initialization script, specify the filebrowserUploadUrl option to point to the API endpoint in your Spring Boot application where images will be uploaded:

<script>
    CKEDITOR.replace('editor', {
        filebrowserUploadUrl: '/uploadImage'
    });
</script>

Conclusion

Integrating image upload functionality in CKEditor with Spring Boot allows for a seamless content creation experience for users. By following the steps outlined in this guide, you can easily implement image uploads with CKEditor and store the images in Amazon S3 using Spring Boot.