How to open a generated PDF file in browser?

I have written a Pdf merger which merges an original file with a watermark.

What I want to do now is to open 'document-output.pdf' file in the browser by a Django view. I already checked Django's related articles, but since my approach is relatively different, I don't directly create the PDF object, using the response object as its "file.", so I am kind of lost.

So, how can I do is in a Django view?

from pyPdf import PdfFileWriter, PdfFileReader
from reportlab.pdfgen.canvas import Canvas
from reportlab.pdfbase import pdfmetrics
from reportlab.pdfbase.ttfonts import TTFont

output = PdfFileWriter()
input = PdfFileReader(file('file.pdf', 'rb'))

# get number of pages
num_pages = input.getNumPages()

# register new chinese font
pdfmetrics.registerFont(TTFont('chinese_font','/usr/share/fonts/truetype/mac/LiHeiPro.ttf'))

# generate watermark on the fly
pdf = Canvas("watermark.pdf")
pdf.setFont("chinese_font", 12)
pdf.setStrokeColorRGB(0.5, 1, 0)
pdf.drawString(10, 830, "你好")
pdf.save()

# put on watermark
watermark = PdfFileReader(file('watermark.pdf', 'rb'))
page1 = input.getPage(0)

page1.mergePage(watermark.getPage(0))

# add processed pdf page
output.addPage(page1)

# then, add rest of pages
for num in range(1, num_pages):
  开发者_开发知识库  output.addPage(input.getPage(num))

outputStream = file("document-output.pdf", "wb")
output.write(outputStream)
outputStream.close()

I know its an older post but we can use the embed tag of html to implement this kind of functionality. For e.g.:

<embed height="100%" width="100%"  name="plugin" src="filename.pdf"  type="application/pdf">

So in your case, you can simply send the response using render to response as:

return render_to_response("abc.html",{"filename":filename})

and in the abc.html you can put this filename (with the path) in the embed tag, as mentioned above.

Hope this helps.

In addition to sending your PDF back to the browser, you can also save some cycles by storing your watermark in a string buffer.

from pyPdf import PdfFileWriter, PdfFileReader
from reportlab.pdfgen.canvas import Canvas
from reportlab.pdfbase import pdfmetrics
from reportlab.pdfbase.ttfonts import TTFont
from django.http import HttpResponse
try:
   from cStringIO import StringIO
except ImportError:
   from StringIO import StringIO

def some_view(request):
   output = PdfFileWriter()
   input = PdfFileReader(file('file.pdf', 'rb'))

   #create response object
   response = HttpResponse(mimetype='application/pdf')
   response['Content-Disposition'] = 'attachment; filename=somefilename.pdf'

   # get number of pages
   num_pages = input.getNumPages()

   #register the font
   pdfmetrics.registerFont(TTFont('chinese_font','/usr/share/fonts/truetype/mac/LiHeiPro.ttf'))

   # generate watermark on the fly
   buffer = StringIO() # create string buffer for PDF
   pdf = Canvas(buffer)
   pdf.setFont("chinese_font", 12)
   pdf.setStrokeColorRGB(0.5, 1, 0)
   pdf.drawString(96, 26, "88888")
   pdf.save()

   # put on watermark from buffer
   watermark = PdfFileReader(buffer)
   page1 = input.getPage(0)

   page1.mergePage(watermark.getPage(0))

   # add processed pdf page
   output.addPage(page1)


   #stream to browser
   outputStream = response
   output.write(response)
   outputStream.close()

return response

I am not sure I follow. If you want the PDF content to be sent to the browser you should use an HttpResponse instance. This line in your code

outputStream = file("document-output.pdf", "wb")

will not serve to write the PDF contents to the response. Instead it looks to me like it will write the contents to a local file, which is not the same.

Update

Based on comment:

How to send PDF content to a HttpResponse object as it will open in the browser, not as an attachment.

AFAIK (if anyone knows better, correct me) this is browser dependent.

If you leave out the Content-Disposition = "attachment; filename=foo.pdf from the response headers you can send the contents to the browser without a specific filename. This prompted my Firefox browser (3.6.10, Ubuntu Jaunty) to ask me if I wanted to open it using a program. On Chrome (6.0.472.62, Ubuntu Jaunty) the file got downloaded as download.pdf without any prompting.

remove 'attachment' from this line with Chris comment

response['Content-Disposition'] = 'attachment; filename=somefilename.pdf'