Per-IP sliding window rate limiter
ocaml-rate-limit: enable MDX on lib/rate_limit.mli, harden doc example
The example used handle_request / process_request / respond_429 as
free functions and didn't run anything. Replaced with a toplevel
[Eio_main.run] block that exhausts the limiter (3 allowed, then
rejected) and asserts on the exact decision values, including the
expected retry_after (60.0 - 3.0 = 57.0). The build now catches drift
in the [decision] type and the sliding-window arithmetic.
+15
-6
+4
lib/dune
+4
lib/dune
+11
-6
lib/rate_limit.mli
+11
-6
lib/rate_limit.mli
···
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{2 Example}
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{[
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-
let limiter = Rate_limit.v ~max_requests:100 ~window_seconds:60.0 ()
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-
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-
let handle_request ~ip ~now =
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-
match Rate_limit.check_and_record limiter ~ip ~now with
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-
| Allowed { remaining } -> process_request ~remaining
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-
| Rejected { retry_after } -> respond_429 ~retry_after
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+
let () =
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+
Eio_main.run @@ fun _env ->
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+
let limiter = Rate_limit.v ~max_requests:3 ~window_seconds:60.0 () in
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let ip = "10.0.0.1" in
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+
let a1 = Rate_limit.check_and_record limiter ~ip ~now:0.0 in
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+
let _a2 = Rate_limit.check_and_record limiter ~ip ~now:1.0 in
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+
let a3 = Rate_limit.check_and_record limiter ~ip ~now:2.0 in
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+
let rejected = Rate_limit.check_and_record limiter ~ip ~now:3.0 in
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+
assert (a1 = Rate_limit.Allowed { remaining = 2 });
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assert (a3 = Rate_limit.Allowed { remaining = 0 });
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assert (rejected = Rate_limit.Rejected { retry_after = 57.0 })
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]} *)
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type t