Setting up Swagger Ui in Firebase Functions Server - node.js

Question

I've developed an API on Firebase Cloud Functions and I want to include a docs path to it.
I'm using swagger and I could successfully test it locally (localhost:PORT/docs) but when I deploy the function to Firebase it's not working, it redirects me to an authorization page.
I think I figured out why this is:
Let's say the name of my Cloud function is cfunc. Then the base url for it is something like https://region-name-project-name.cloudfunctions.net/cfunc. Based on how I included the swagger documentation:
const swaggerDoc = require('./docs/swagger.config.json')
app.use(
'/docs',
allowCors,
swaggerUi.serve,
swaggerUi.setup(swaggerDoc, {
customCssUrl: '/assets/swagger.css',
customSiteTitle: 'My Function Title',
customfavIcon: '/assets/logo.ico',
swaggerOptions: {
supportedSubmitMethods: [] //to disable the "Try it out" button
}
})
)
the docs should be located at https://region-name-project-name.cloudfunctions.net/cfunc/docs. When I try to access that URL, watching "Network" in my browser DevTools, it attempts a GET at that URL with response 304 and then redirects to https://region-name-project-name.cloudfunctions.net/docs and that's what brings up the Google Authentication page, since there's no Cloud Function named "docs" so Google thinks I'm trying to access something else in Firebase Cloud Functions (the same thing happens if I do something like https://region-name-project-name.cloudfunctions.net/tomato)
But I still don't know how to fix this redirect or why it's happening. I tried adding the Cloud Function URL to the host parameter of the swagger.config.json file, and some modifications to CORS, like allowing more Request Methods, adding json as content type, allowing authentication on headers, but nothing seems to be working.
Hope I was clear enought, if not tell me any other info you need (it's one of my first posts here :B)

Answer 1

Found the SOLUTION
After testing a BUNCH of different things, I found out that the redirection was in fact happening always removing one slice of the path after, for example I changed the docs endpoint to '/something/docs' and when accessing the URL that would be https://region-name-project-name.cloudfunctions.net/cfunc/something/docs it redirected to https://region-name-project-name.cloudfunctions.net/cfunc/docs which did not bring up the Google Authentication thing but now wasn't a valid path for my docs so it returned a 'Cannot GET /cfunc/docs'.
For some reason this redirection DOES NOT happen if you add an extra forward slash ('/') at the end of the documentation URL. So, in the first case, where the endpoint for the documentation is only '/docs', accessing the URL https://region-name-project-name.cloudfunctions.net/cfunc/docs/ does it. I do not know why that is, I'm probably posting an Issue on the swagger repo, but if someone has some extra data on why or how to make it work otherwise it would be awesome to hear.
Hope this helps someone else!
EDIT:
Oh and another thing I forgot, it's apparently better if you setup swagger-ui as if you were using express Router, even if you are not (maybe Firebase loads the Cloud Function with something like a router), so instead of app.use('/docs', swagger-ui.serve, swagger-ui.setup(swagger-file)) do app.use('/docs', swagger-ui.serve) and then app.get('/docs', swagger-ui.setup(swagger-file))