Struct WhenActive 

pub struct WhenActive { /* private fields */ }

A route that is not there yet.

Why 404 and not 403

A 403 is an admission. It says “there is something at this address, and you are not it” — which tells anyone who tries the URL that the feature exists, roughly what it is called, and that it is worth coming back for. Half-built features get found this way: somebody diffs the routes between two deploys, walks the ones that answer 403, and reads the names.

A route behind a flag that is off has not shipped. The honest answer, and the same one the router gives for a path nobody ever wrote, is 404 — and it is byte-for-byte the router’s own 404 here, because a body that differed would give the whole thing away again.

This is concealment, not authorization. It keeps a URL from being interesting; it does not keep anybody out. If the feature behind the flag must not be reachable by the people outside the rollout — because it costs money, or exposes somebody else’s data — put rustlavel_rbac::Can in front of it as well. A flag is a release tool.

What it does to the request

On the way through, the ScopedFlags it resolved is attached to the request, so a handler that asks the same or another flag reuses the memo instead of running the resolvers again.

Implementations

impl WhenActive

pub fn new(flag: impl Into<String>) -> Self

Guard the routes below with one flag.

pub fn flag(&self) -> &str

The flag this guard is checking.

Trait Implementations

impl Clone for WhenActive

fn clone(&self) -> WhenActive

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for WhenActive

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Middleware for WhenActive

fn handle(&self, request: Request, next: Next) -> BoxFuture<Response>