Previously added text disappears when new text is added

[work-wajeeh]

I've a model LibraryDocument and I'm using following method to add text to the pdf document. It just keeps the most recent text added to the document and previous changes are removed. Not sure what I'm missing here

def add_text(text, pos=[100,100])
  downloadPDF = Tempfile.new('download_pdf')
  File.open(downloadPDF.path, "w") do |f|
    document_path = Addressable::URI.parse(doc_url).normalize.to_s
    IO.copy_stream(URI.open(document_path), f)
  end
  doc = HexaPDF::Document.open(downloadPDF)
  (doc.pages[0]).canvas(type: :overlay).font('Helvetica', size: 12).fill_color(0,0,0).text(text, at: pos)
  io = StringIO.new(''.b)
  doc.write(io)

  t = Tempfile.new("test_temp")
  t.write(io.string)
  t.rewind

  # upload to S3
  filesize = File.size(t.path)
  wsS3 = Aws::S3::Resource.new(:region => "us-east-1")
  key = document.url #document is an instance of LibraryDocument
  s3obj = wsS3.bucket($UPLOADBUCKET).object(key)
  s3obj.upload_file(t.path, :acl => "public-read", :content_type => "application/pdf")
  t.close
  t.unlink
end

[gettalong]

I'm not sure what you are doing in that method, to be honest. You are writing the PDF document to the StringIO instance named io but after that you don't use that variable anymore, effectively throwing away the written PDF document.

Could you please clarify?

[work-wajeeh]

@gettalong my bad. I'm using io to write into the TempFile object t t.write(io.string) I've update the code. Apologies

[gettalong]

Okay, a few points that should make the code easier to follow:

• You should be able to use doc = HexaPDF::Document.new(io: URI.open(document_path))
• and doc.write(t) where t is the tempfile.

There is nothing wrong with HexaPDF here. Maybe you are downloading the original file instead of the modified one?