51 lines
2.0 KiB
OCaml
51 lines
2.0 KiB
OCaml
(**************************************************************************)
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(* *)
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(* Copyright (c) 2014 - 2017. *)
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(* Dynamic Ledger Solutions, Inc. <contact@tezos.com> *)
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(* *)
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(* All rights reserved. No warranty, explicit or implicit, provided. *)
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(* *)
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(**************************************************************************)
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type t = {
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allowed_headers : string list ;
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allowed_origins : string list ;
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}
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let default = { allowed_headers = [] ; allowed_origins = [] }
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let check_origin_matches origin allowed_origin =
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String.equal "*" allowed_origin ||
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String.equal allowed_origin origin ||
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begin
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let allowed_w_slash = allowed_origin ^ "/" in
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let len_a_w_s = String.length allowed_w_slash in
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let len_o = String.length origin in
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(len_o >= len_a_w_s) &&
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String.equal allowed_w_slash @@ String.sub origin 0 len_a_w_s
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end
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let find_matching_origin allowed_origins origin =
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let matching_origins =
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List.filter (check_origin_matches origin) allowed_origins in
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let compare_by_length_neg a b =
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~- (compare (String.length a) (String.length b)) in
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let matching_origins_sorted =
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List.sort compare_by_length_neg matching_origins in
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match matching_origins_sorted with
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| [] -> None
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| x :: _ -> Some x
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let add_headers headers cors origin_header =
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let cors_headers =
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Cohttp.Header.add_multi headers
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"Access-Control-Allow-Headers" cors.allowed_headers in
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match origin_header with
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| None -> cors_headers
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| Some origin ->
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match find_matching_origin cors.allowed_origins origin with
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| None -> cors_headers
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| Some allowed_origin ->
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Cohttp.Header.add_multi cors_headers
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"Access-Control-Allow-Origin" [allowed_origin]
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