Rasa: Expose filename header in model training api

[Ezhvsalate]

Rasa version: Rasa 1.10.1

Python version: 3.6.9

Operating system: Ubuntu 18.04.3 LTS (Bionic Beaver)

Issue:

I train a model using HTTP /model/train API and want to get a trained model filename as response header as defined in docs.

Unfortunately it seems like I can't do this: browser doesn't see response 'filename' header.
All I get are following:

HTTP/1.1 200 OK
Connection: keep-alive
Keep-Alive: 5
Access-Control-Allow-Origin: http://localhost:3000
Access-Control-Allow-Credentials: true
Access-Control-Allow-Headers: content-type
Access-Control-Max-Age: None
Access-Control-Allow-Methods: DELETE, GET, HEAD, OPTIONS, PATCH, POST, PUT
Vary: Origin
Content-Length: 0

Looks like this is issue about 'Access-Control-Expose-Headers'. Can we add 'filename' to exposed headers?

[sara-tagger]

Thanks for the issue, @melindaloubser1 will get back to you about it soon!

You may find help in the docs and the forum, too 🤗

[melindaloubser1]

Can you post the request you're making/how you're making it? I do see the filename header returned with the request below:

curl --request POST --url http://localhost:5005/model/train \ 
--output model.tar.gz   \
  --header 'content-type: application/json' \
  --data '{
  "domain": "intents:\n  - greet\n  - goodbye\n  - affirm\n  - deny\n  - mood_great\n  - mood_unhappy\n\nactions:\n  - utter_greet\n  - utter_cheer_up\n  - utter_did_that_help\n  - utter_happy\n  - utter_goodbye\n\ntemplates:\n  utter_greet:\n  - text: \"Hey! How are you?\"\n\n  utter_cheer_up:\n  - text: \"Here is something to cheer you up:\"\n    image: \"https://i.imgur.com/nGF1K8f.jpg\"\n\n  utter_did_that_help:\n  - text: \"Did that help you?\"\n\n  utter_happy:\n  - text: \"Great carry on!\"\n\n  utter_goodbye:\n  - text: \"Bye\"",
  "config": "language: en\npipeline: supervised_embeddings\npolicies:\n  - name: MemoizationPolicy\n  - name: KerasPolicy",
  "nlu": "## intent:greet\n- hey\n- hello\n- hi\n## intent:goodbye\n- bye\n- goodbye\n- have a nice day\n- see you\n## intent:affirm\n- yes\n- indeed\n## intent:deny\n- no\n- never\n## intent:mood_great\n- perfect\n- very good\n- great\n## intent:mood_unhappy\n- sad\n- not good\n- unhappy",
  "stories": "## happy path\n* greet\n\n  - utter_greet\n\n* mood_great\n\n  - utter_happy\n\n## sad path 1\n* greet\n\n  - utter_greet\n\n* mood_unhappy\n\n  - utter_cheer_up\n\n  - utter_did_that_help\n\n* affirm\n\n  - utter_happy\n\n## sad path 2\n* greet\n\n  - utter_greet\n\n* mood_unhappy\n\n  - utter_cheer_up\n\n  - utter_did_that_help\n\n* deny\n\n  - utter_goodbye\n\n## say goodbye\n* goodbye\n\n  - utter_goodbye",
  "force": false,
  "save_to_default_model_directory": true
}' --dump-header header.txt

header.txt contains:

HTTP/1.1 100 Continue

HTTP/1.1 200 OK
Connection: keep-alive
Keep-Alive: 5
filename: 20200629-154807.tar.gz
Content-Disposition: attachment; filename="20200629-154807.tar.gz"
Access-Control-Allow-Origin: *
Access-Control-Allow-Credentials: true
Content-Length: 1916881
Content-Type: application/x-tar

[Ezhvsalate]

@melindaloubser1, sure, curl or other tool like that will see custom header. But for js code in browser it won't be accessible by default. Please check this link for more info.

I have prepared a demo app here, you can reproduce this yourself.

It starts a simple react app, containing one button which launches model training at http://localhost:5005 and prints to browser console available response's headers:

Then add the line here to configure sanic-cors:

 app.config.CORS_EXPOSE_HEADERS = '*'

After that much more info is available to browser:

Or less broadly:

 app.config.CORS_EXPOSE_HEADERS = 'filename'

If one of options above is suitable for you I can create a PR.

[melindaloubser1]

Ok that makes sense! Yes, if you could open a PR for exposing just filename additionally that'd be great.

[Ezhvsalate]

@melindaloubser1 created a PR. Please check it when you have time.

[melindaloubser1]

@Ezhvsalate I don't think the commit you linked to is actually part of a PR, I left a comment on it