OPTIONS generated by CORS doesn't work correctly in local

[jsanchezs]

First of all, thank you for this awesome framework. Really easy to use, I like it a lot.

I'm developing an API that has to accept CORS and i'm having troubles with the OPTIONS methods.

The problem is easy to reproduce:
In app.py

...
@app.route('/test', methods=['POST'], cors=True)
def test_cors():
  return {'hello': 'world'}

Then, run it in local: chalice local --port=8100

When you try to do the first OPTIONS curl, everything works =)

curl -H "Origin: http://example.com" \                                                      
  -H "Access-Control-Request-Method: POST" \
  -H "Access-Control-Request-Headers: X-Requested-With" \
  -X OPTIONS --verbose \
  http://localhost:8100/test

Response:

*   Trying ::1...
* TCP_NODELAY set
* Connection failed
* connect to ::1 port 8100 failed: Connection refused
*   Trying 127.0.0.1...
* TCP_NODELAY set
* Connected to localhost (127.0.0.1) port 8100 (#0)
> OPTIONS /test HTTP/1.1
> Host: localhost:8100
> User-Agent: curl/7.51.0
> Accept: */*
> Origin: http://example.com
> Access-Control-Request-Method: POST
> Access-Control-Request-Headers: X-Requested-With
>
* HTTP 1.0, assume close after body
< HTTP/1.0 200 OK
< Server: BaseHTTP/0.6 Python/3.6.0
< Date: Thu, 07 Sep 2017 16:02:02 GMT
< Access-Control-Allow-Origin: *
< Access-Control-Allow-Headers: Authorization,Content-Type,X-Amz-Date,X-Amz-Security-Token,X-Api-Key
< Access-Control-Allow-Methods: POST,OPTIONS
<
* Curl_http_done: called premature == 0
* Closing connection 0

But the next OPTIONS curl will not end never =(

*   Trying ::1...
* TCP_NODELAY set
* Connection failed
* connect to ::1 port 8100 failed: Connection refused
*   Trying 127.0.0.1...
* TCP_NODELAY set
* Connected to localhost (127.0.0.1) port 8100 (#0)
> OPTIONS /test HTTP/1.1
> Host: localhost:8100
> User-Agent: curl/7.51.0
> Accept: */*
> Origin: http://example.com
> Access-Control-Request-Method: POST
> Access-Control-Request-Headers: X-Requested-With
>
< HTTP/1.1 200 OK
< Server: BaseHTTP/0.6 Python/3.6.0
< Date: Thu, 07 Sep 2017 16:02:03 GMT
< Access-Control-Allow-Origin: *
< Access-Control-Allow-Headers: Authorization,Content-Type,X-Amz-Date,X-Amz-Security-Token,X-Api-Key
< Access-Control-Allow-Methods: POST,OPTIONS
* no chunk, no close, no size. Assume close to signal end

It stops in * no chunk, no close, no size. Assume close to signal end. It seems like the server only send the close signal only in the first call. If you stop the second curl and try it again, it wont stop neither.

Do you have the same problem? Can you reproduce it?

P.S.: I'm using macOS, but I hope that is not a problem to do the local development =P

[stealthycoin]

Yep this looks like a bug to me. HTTP 1.1 defaults to not closing the connection unless the Connection: Close header is sent if there is no body.

Edit: To follow up on that, when I try this locally it hangs on the first OPTIONS request. I can't replicate getting the first one to succeed.

[JoeStech]

I'm seeing this OPTIONS behavior when app.debug = True with Chalice 1.0.2, both locally and when deployed. Might be related, just wanted to mention it. I know I have some other issue related to my 'vendor' packages, but having a difficult time debugging because this OPTIONS behavior seems to be masking the real problem.