如何使用 Python 在谷歌云存储中拆分 PDF

Question

I have a single PDF that I would like to create different PDFs for each of its pages. How would I be able to so without downloading anything locally? I know that Document AI has a file splitting module (which would actually identify different files.. that would be most ideal) but that is not available publicly.

I am using PyPDF2 to do this curretly

    list_of_blobs = list(bucket.list_blobs(prefix = 'tmp/'))
    print(len(list_of_blobs))
    list_of_blobs[1].download_to_filename('/' + list_of_blobs[1].name)
    
    inputpdf = PdfFileReader(open('/' + list_of_blobs[1].name, "rb"))

    individual_files = []
    stream = io.StringIO()
    
    for i in range(inputpdf.numPages):
        output = PdfFileWriter()
        output.addPage(inputpdf.getPage(i))
        individual_files.append(output)
        with open("document-page%s.pdf" % (i + 1), "a") as outputStream:
            outputStream.write(stream.getvalue())
            #print(outputStream.read())
            with open(outputStream.name, 'rb') as f:
                data = f.seek(85)
                data = f.read()
                individual_files.append(data)
                bucket.blob('processed/' +  "doc%s.pdf" % (i + 1)).upload_from_string(data, content_type='application/pdf')

In the output, I see different PyPDF2 objects such as <PyPDF2.pdf.PdfFileWriter object at 0x12a2037f0> but I have no idea how I should proceed next. I am also open to using other libraries if those work better.

Answer 1

There were two reasons why my program was not working:

1. I was trying to read a file in append mode (I fixed this by moving the second with(open) block outside of the first one,
2. I should have been writing bytes (I fixed this by changing the open mode to 'wb' instead of 'a')

Below is the corrected code:

if inputpdf.numPages > 2:
   for i in range(inputpdf.numPages):
      output = PdfFileWriter()
      output.addPage(inputpdf.getPage(i))
      with open("/tmp/document-page%s.pdf" % (i + 1), "wb") as outputStream:
           output.write(outputStream)
      with open(outputStream.name, 'rb') as f:
           data = f.seek(0)
           data = f.read()
           #print(data)
           bucket.blob(prefix + '/processed/' +  "page-%s.pdf" % (i + 1)).upload_from_string(data, content_type='application/pdf')
      stream.truncate(0)

Answer 2

To split a PDF file in several small file (page), you need to download the data for that. You can materialize the data in a file (in the writable directory /tmp ) or simply keep them in memory in a python variable.

In both cases:

• The data will reside in memory
• You need to get the data to perform the PDF split.

---

If you absolutely want to read the data in streaming (I don't know if it's possible with PDF format,!), you can use the streaming feature of GCS . But, because there isn't CRC on the downloaded data, I won't recommend you this solution, except if you are ready to handle corrupted data, retries and all related stuff.