Add rate limit handling

1 files changed, 29 insertions, 0 deletions

diff --git a/lib/rl.ml b/lib/rl.ml
new file mode 100644
index 0000000..316abcf
--- /dev/null
+++ b/lib/rl.ml
@@ -0,0 +1,29 @@
+open Core
+open Async
+
+module RouteMap = Map.Make(String)
+
+type rl = {
+    limit: int;
+    remaining: int;
+    reset: int;
+}
+
+type t = ((rl, read_write) Mvar.t) RouteMap.t
+
+let rl_of_header h =
+    let module C = Cohttp.Header in
+    match C.get h "X-RateLimit-Limit", C.get h "X-RateLimit-Remaining", C.get h "X-RateLimit-Reset" with
+    | Some lim, Some rem, Some re ->
+        let limit = Int.of_string lim in
+        let remaining = Int.of_string rem in
+        let reset = Int.of_string re in
+        Some { limit; remaining; reset; }
+    | _ -> None
+
+let update = RouteMap.update
+let empty : t = RouteMap.empty
+let find = RouteMap.find
+let find_exn m s = match find m s with
+    | Some r -> r
+    | None -> raise (Not_found_s (String.sexp_of_t s))
\ No newline at end of file