Application-wide route prefix management

[loppear]

Rather than modules all managing a "baseUrl" config and exposing that as a responder for other modules to retrieve and use in constructing sub-urls, provide a general mechanism for prefixing routes. In effect, routes become a namespace with known values (commonly based on module name) (/admin/, /users/), and router handles where those actually respond.

Proposal

Router config gets a routePrefixes key, with possible values like:

"routePrefixes": {
  "/": "/myapp/"
  "/users": "/staff",
  "/admin": "/manage"
}

These are all checked for initial matches to routes on startup when routes are actually registered with express, so this example would produce urls like:

/myapp/
/myapp/staff
/myapp/manage

And router provides helpers (responder and ejs) for finding the real value of a route for redirects or links:

  router.realPath("/admin/whatever").then(::res.redirect)

  <a href="<%= realPath("/users/profile") %>">

[mjreich]

Would adding router middleware to auto redirect on found mappings handle most cases? I guess there would still be the possibility for collisions.

[mjreich]

Also, this feels like it could very easily break everything unless everyone opts in.

[loppear]

Yes, hard coded routes would be liable to break, everyone would need to use realPath. Just like right now everyone needs to know that they need to construct user/admin paths by pulling some global config.

I don't think redirecting middleware helps the CAIT case where the app itself is mounted somewhere that is shared. Same issue, everyone would be expected to use realPath.

[mjreich]

Ok, good points. I think this is a fine solution then.