'after_request' runs but headers don't get set

import bottle


app = bottle.Bottle()

@app.hook('after_request')
def fn():
    print(dict(bottle.response.headers))
    bottle.response.headers['abc'] = 'yes'
    print(dict(bottle.response.headers))


@app.get('/')
def asdf():
    return ''


app.run()

This code runs properly. I’m able to get the headers when I make a request from another program. However if I change the route to

@app.get('/')
def asdf():
    bottle.abort(424)

The hook gets run since I can see it in the server process log

Bottle v0.12.13 server starting up (using WSGIRefServer())...
Listening on http://127.0.0.1:8080/
Hit Ctrl-C to quit.

{}
{'abc': 'yes'}
127.0.0.1 - - [15/Jan/2019 21:23:03] "GET / HTTP/1.1" 424 726

but the header is not received in the program which made the call. That program is also quiet simple. curl http://localhost:8080 -D-

I saw #978 and was facing the same problem. Some of the UI frameworks using our APIs break if the error response does not have CORS headers.

Am I doing something wrong?

[defnull]

It’s solved in 0.13 but this gets reported quite often for 0.12, so I’ll look into a backport or pull requests fixing this specific issue for 0.12. Let’s keep this issue open for now.

[nicoabie]

This issue is still valid in latest stable release which is 0.12.16 at the moment of writting this comment.

Particularly fails when working with static_files:

@hook('after_request')
def enable_cors_after_request_hook():
   print("add_cors_headers")
    response.headers['Access-Control-Allow-Origin'] = '*'
    response.headers['Access-Control-Allow-Methods'] = 'GET, POST, PUT, OPTIONS'
    response.headers['Access-Control-Allow-Headers'] = 'Origin, Accept, Content-Type, X-Requested-With, X-CSRF-Token'

@get('/benchmark/<feed>/<strategy>/<name>')
def bench_get(feed, strategy, name):
    return static_file(name + '.json', root="../benchs/{}/{}".format(feed, strategy))

It calls the function but header are not set.