将压缩的 PDF 文件内容从客户端发送到后端服务器

Question

I'm using ilovepdf to compress a pdf file uploaded at the client side. I get the compressed file contents as the response.

Ideally what I want is to -:

• Make a file(PDF) at the client side with file contents received response.
• Attach the document to the file upload DOM element.
• Submit the file to the backend.

But it looks like reading/writing a file with contents at client side(browser) is forbidden. So above could not be acheived. I also tried attaching just compressed file contents to a DOM element and submitting to backend with formdata, however, when i save file with contents received at backend, I find the file as damaged or cannot open.

Below code is triggered for download from ilovepdf server and upload to my server.

function downloadPDF() {
  $.ajax({
    type: 'GET',
    headers: {
      'Authorization': 'Bearer ' + token
    },
    url: "https://" + server + "/v1/download/" + task,
    success: function(response) {
      var form = new FormData();
      form.append("file", response);
      $.ajax({
        type: 'POST',
        url: "/properties/compressed",
        processData: false,
        contentType: false,
        data: form,
        success: function(response) {
          console.log("sent to server")
        }
      });
    }
  });
}

Answer 1

You can generate the PDF from your server by using wicked_pdf gem and encode the same in base64 return the base64 encoded string to client server and the on your client server you can use this code for download the PDF:

window.downloadPDF = function downloadPDF() {

    var dlnk = document.getElementById('dwnldLnk');
    dlnk.href = pdf; <this would be your return encoded string in response>

    dlnk.click();


    alert('toma');
}