string argument expected, got 'bytes'

When I try to create a PDF, I get the error “string argument expected, got 'bytes”.

I am using the djangoproject demo on Python 3.5 and am running the pre of xhtml2pdf as instructed in the readme.

The error happens when the following line is reached, which is line 35

        pdf = pisa.CreatePDF(
            StringIO(request.POST["data"]),
            result
            )

More specifically, it seems that the “result” variable on line 37 is not actually a String variable, but rather a Bytes (or so seen by the code). When I run a type() on “result” it returns <class '_io.StringIO'> which seems that it should be correct but is still erroring out.

Django is also highlighting line 183 of the document.py file as to where this error is happening which contains the following:

context.dest.write(data)  # TODO: context.dest is a tempfile as well... 

Is there any workaround that has been found for this or even a known reason as to why it’s happening?

[ghost]

I’ve solved the issue. Changing line 13 to the following seems to fix the issue:

from io import StringIO, BytesIO

and changing line 34 to the following:

result = BytesIO()

[iansprice]

Any further thoughts on this? It is blocking for me and the fix above isn’t helping. Here’s a traceback (inline css in template)-

Internal Server Error: /bc/draw/830__ball__CS____+__1138/
Traceback (most recent call last):
File "/app/.heroku/python/lib/python3.5/site-packages/django/core/handlers/base.py", line 149, in get_response
response = self.process_exception_by_middleware(e, request)
File "/app/.heroku/python/lib/python3.5/site-packages/django/core/handlers/base.py", line 147, in get_response
response = wrapped_callback(request, *callback_args, **callback_kwargs)
File "/app/bc/views.py", line 627, in drawing
pisa.CreatePDF(html, dest=file1, link_callback=callbacky)
File "/app/.heroku/python/lib/python3.5/site-packages/xhtml2pdf/document.py", line 97, in pisaDocument
encoding, context=context, xml_output=xml_output)
File "/app/.heroku/python/lib/python3.5/site-packages/xhtml2pdf/document.py", line 59, in pisaStory
pisaParser(src, context, default_css, xhtml, encoding, xml_output)
File "/app/.heroku/python/lib/python3.5/site-packages/xhtml2pdf/parser.py", line 702, in pisaParser
context.parseCSS()
File "/app/.heroku/python/lib/python3.5/site-packages/xhtml2pdf/context.py", line 522, in parseCSS
self.css = self.cssParser.parse(self.cssText)
File "/app/.heroku/python/lib/python3.5/site-packages/xhtml2pdf/w3c/cssParser.py", line 443, in parse
src, stylesheet = self._parseStylesheet(src)
File "/app/.heroku/python/lib/python3.5/site-packages/xhtml2pdf/w3c/cssParser.py", line 531, in _parseStylesheet
src, stylesheetImports = self._parseAtImports(src)
File "/app/.heroku/python/lib/python3.5/site-packages/xhtml2pdf/w3c/cssParser.py", line 615, in _parseAtImports
stylesheet = self.cssBuilder.atImport(import_, mediums, self)
File "/app/.heroku/python/lib/python3.5/site-packages/xhtml2pdf/w3c/css.py", line 909, in atImport
return cssParser.parseExternal(import_)
File "/app/.heroku/python/lib/python3.5/site-packages/xhtml2pdf/context.py", line 404, in parseExternal
result = self.parse(cssFile.getData())
File "/app/.heroku/python/lib/python3.5/site-packages/xhtml2pdf/w3c/cssParser.py", line 443, in parse
src, stylesheet = self._parseStylesheet(src)
File "/app/.heroku/python/lib/python3.5/site-packages/xhtml2pdf/w3c/cssParser.py", line 523, in _parseStylesheet
src = self.re_comment.sub('', src)
TypeError: cannot use a string pattern on a bytes-like object