HTML-to-PDF Conversion Tool

// Spring Boot Controller
@RestController
@RequestMapping("/api/pdf")
public class HtmlToPdfController {

    @PostMapping(value = "/from-html", consumes = MediaType.TEXT_PLAIN_VALUE)
    public ResponseEntity htmlToPdf(@RequestBody String html) throws Exception {
        byte[] pdf = renderHtmlToPdf(html);
        return ResponseEntity.ok()
                .header(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=converted.pdf")
                .contentType(MediaType.APPLICATION_PDF)
                .body(pdf);
    }

    @GetMapping(value = "/from-url")
    public ResponseEntity urlToPdf(@RequestParam String url) throws Exception {
        String html = fetchHtmlFromUrl(url);
        byte[] pdf = renderHtmlToPdf(html);
        return ResponseEntity.ok()
                .header(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=page.pdf")
                .contentType(MediaType.APPLICATION_PDF)
                .body(pdf);
    }

    private byte[] renderHtmlToPdf(String html) throws Exception {
        try (ByteArrayOutputStream os = new ByteArrayOutputStream()) {
            PdfRendererBuilder builder = new PdfRendererBuilder();
            builder.withHtmlContent(html, "");
            builder.toStream(os);
            builder.run();
            return os.toByteArray();
        }
    }
    
    private String fetchHtmlFromUrl(String url) {
        // Implementation to fetch HTML from a URL
        return "";
    }
}