Problem with binary files

I’m trying to return an Excel file as an attachment. Here’s my code:

content_type = (
    "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet"
)
response = HttpResponse(content=data, content_type=content_type)
response["Content-Disposition"] = 'attachment; filename="{0}"'.format(filename)
return response

First I had an encoding error:

'utf-8' codec can't decode byte 0xc0 in position 10: invalid start byte: UnicodeDecodeError
Traceback (most recent call last):
  File "/opt/apig_wsgi.py", line 44, in handler
    return response.as_apig_response()
  File "/opt/apig_wsgi.py", line 149, in as_apig_response
    response["body"] = self.body.getvalue().decode("utf-8")
UnicodeDecodeError: 'utf-8' codec can't decode byte 0xc0 in position 10: invalid start byte

So I activated the binary mode:

app = make_lambda_handler(application, binary_support=True)

I have no more errors but my file can’t be read 😦

[adamchainz]

I added a few more words to the documentation to make this easier to discover in the future: 6e18125459fac889ecbf0ca2e48200a8a715577c

[adamchainz]

Aha 😃