307 redirects within actions do not result in a new POST request being made

[edwardbrowncross]

What version of Remix are you using?

1.7.0

Steps to Reproduce

Inside an action, redirect with a 307 status code. For example:

throw redirect(request.url, {
    status: 307,
    headers: {
        'Set-Cookie': refreshedAuthToken,
    },
});

Expected Behavior

The semantic meaning of 307 is

make another request with the same method at the new location

Therefore I expect the code above to be interpreted as

Call this action again (making a POST request to this endpoint)

Actual Behavior

It makes a GET request to the URL associated to the action (the normal behaviour of a 302 redirect on the web)

[edwardbrowncross]

My current hack to make this work as I expected is to instead construct a response like this:

throw new Response(null, {
    status: 204,
    headers: {
        'Set-Cookie': cookie,
        'x-three-zero-seven': 'true',
        'Location': request.url,
    },
});

And then have a handleDataRequest function exported from entry.server.tsx like this:

export const handleDataRequest: HandleDataRequestFunction = (response: Response) => {
    if (response.headers.has('x-three-zero-seven')) {
        return new Response(response.body, {
            status: 307,
            headers: response.headers,
        });
    }
    return response;
};

This works since the handleDataRequest is called after the server code that turns redirects into x-remix-redirect responses has already happened.

[kiliman]

That's an odd status. It assumes the user-agent still has access to the originally posted data.

[machour]

Really interesting issue, thanks!
MDN docs for reference: https://developer.mozilla.org/en-US/docs/Web/HTTP/Status/307

[brophdawg11]

Very interesting indeed!

It assumes the user-agent still has access to the originally posted data.

I don't think this is a problem on our end, as we create the Request from source "submission" data, so we should still have the source data available to create another Request in response.

Based on this wording, it sounds like preserving the method is the right behavior in most but not all 3xx cases:

With 302, some old clients were incorrectly changing the method to GET

I'll do some deeper reading on that to be sure, but at a very quick glance it sounds like maybe 301/303 changing to a GET is ok, but 302/307/308 should preserve the method.

Update: @machour is probably correct below that we shouldn't change 302

[machour]

@brophdawg11 to continue the quote:

the behavior with non-GET methods and 302 is then unpredictable on the Web

As far as I remember, I've never seen a 302 doing something other than GET. I'm not sure we should start preserving the method for 302, as it would break a lot of apps..

[brophdawg11]

remix-run/react-router#9597 adds this 307/308 handling to react-router, and Remix should pick that up once we finish moving Remix onto React Router 6.4

[brophdawg11]

We finished the above work in Remix 1.10.0 so this should be handled correctly now. I'm going to close this out but please re-open if you are still running into issues!