wrong redirects when using Volto ?

[mamico]

While working on pull requests plone/volto#4821 and plone/volto#4826, I encountered the following anomalous behavior:

The page "foo" was renamed to "bar".
Volto published with seamless mode.
Inside a page, there is a REST API call, for example, a GET_CONTENT request to "/foo".
The call is transformed into a backend request like this (managed by superagent or the browser):

wget http://localhost:8080/VirtualHostBase/http/localhost:3000/Plone/++api++/VirtualHostRoot/foo -S --header="Accept: application/json"

The backend responds with:

HTTP/1.1 302 Found
Content-Type: application/json
Location: http://localhost:3000/bar

At this point, superagent (or the browser) autonomously follows the redirect and makes a request that returns an HTML response, which is then ignored and replaced with a 301 exception here:

https://github.com/plone/volto/blob/9c5b4ccf94281e2849ca9b66e74cafe7f5ef87cb/src/helpers/Api/Api.js#L102

However, in a block, this exception might not be correctly handled, and actually would probably not be the most appropriate way to handle it.

Personally, I see two approaches to address this issue (the first being my preferred option):

1. Handle the superagent REST redirects to rewrite the redirect location.
2. Modify plone.rest to bring back ++api++ on the right side of the Virtual Host Monster (VHM), similar to how it was done with the legacy traverser.

[djay]

@mamico This is the same problem outlined in plone/volto#4800. I think (2) is the solution. api redirect should include ++api++ in it even with VHM.

[mamico]

@mamico This is the same problem outlined in plone/volto#4800. I think (2) is the solution. api redirect should include ++api++ in it even with VHM.

Yes. Exactly the same. Thanks

But I do not know whether the solution could also be, simply: change VHM currently used in Volto (as in documentation and as default for development)

http://localhost:8080/VirtualHostBase/http/localhost:3000/Plone/++api++/VirtualHostRoot/foo

to

http://localhost:8080/VirtualHostBase/http/localhost:3000/Plone/VirtualHostRoot/++api++/foo

\cc @sneridagh

[djay]

@mamico How you do your VHM is up to the user. We use the internal VHM rules and this bug is breaking volto for us.
So the fix should be that regardless of how you do VHM, an api call should redirect to an api call.

We have already done a PR on volto to fix the fact that volto relies on this bug + the specific VHM config to work currently - plone/volto#4834

[davisagli]

This was fixed a while back in plone/volto#4854