"Generator raised StopIteration" error when sending static file from filesystem

[miguelgrinberg]

Discussed in #142

^{Originally posted by ned-pcs June 6, 2023}
I really like Microdot (which greatly resembles Sinatra, which I've used a lot in Ruby).

I'm using the latest version of Microdot-asyncio on an ESP32.
I would like to pre-compile my static files into frozen strings (and use pkg_resources.resource_stream('static', 'filename')).
I've tried both that method (which returns an io.BytesIO object), and serving these files from my filesystem.
I've tried returning an opened file handle in the Response, as well as using send_file().
In all of the above cases, what I get is a RuntimeError: generator raised StopIteration exception:

Send file /lib/static/js/toast.js
Response header {'Content-Type': 'application/javascript', 'Cache-Control': 'max-age=86400'}
Traceback (most recent call last):
  File "uasyncio/core.py", line 1, in run_until_complete
  File "microdot/microdot_asyncio.py", line 269, in serve
  File "microdot/microdot_asyncio.py", line 337, in handle_request
  File "microdot/microdot_asyncio.py", line 155, in write
RuntimeError: generator raised StopIteration

Templates (using utemplate) and static strings work fine in the Responses.

Here's how I'm trying to return an opened file:

f = open(filename, 'rb')
return Response(body=f, status_code=status_code, headers=response_header)

Using send_file():

return send_file(filename, status_code=status_code, content_type=content_type)

Sending from compiled resources:

f = pkg_resources.resource_stream('static', fname)
return Response(body=f, status_code=status_code, headers=response_header)

or sending from compiled resources using send_file():

f = pkg_resources.resource_stream('static', fname)
return send_file(filename, status_code=status_code, content_type=content_type, stream=f)

Any suggestions?

[miguelgrinberg]

I believe Microdot 2 (just released today) addresses this problem. If you get a chance to upgrade, please let me know if there are any remaining issues.