mte/unikernel/duniverse/ocaml-caqti/caqti/lib-template/request.ml
2025-11-11 02:07:51 +01:00

92 lines
2.8 KiB
OCaml

(* Copyright (C) 2017--2025 Petter A. Urkedal <paurkedal@gmail.com>
*
* This library is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or (at your
* option) any later version, with the LGPL-3.0 Linking Exception.
*
* This library is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
* License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* and the LGPL-3.0 Linking Exception along with this library. If not, see
* <http://www.gnu.org/licenses/> and <https://spdx.org>, respectively.
*)
[@@@alert "-caqti_private"]
module Log = (val Logs.src_log (Logs.Src.create "caqti"))
type prepare_policy =
| Direct
| Dynamic
| Static
type ('a, 'b, +'m) t = {
id: int option;
prepare_policy: prepare_policy;
query: Dialect.t -> Query.t;
param_type: 'a Row_type.t;
row_type: 'b Row_type.t;
row_mult: 'm Row_mult.t;
} constraint 'm = [< `Zero | `One | `Many]
let last_id = ref (-1)
let create prepare_policy (param_type, row_type, row_mult) query =
let id =
(match prepare_policy with
| Direct -> None
| Static | Dynamic -> incr last_id; Some !last_id)
in
{id; prepare_policy; query; param_type; row_type; row_mult}
let prepare_policy request = request.prepare_policy
let param_type request = request.param_type
let row_type request = request.row_type
let row_mult request = request.row_mult
let query_id request = request.id
let query request = request.query
let empty_subst _ = raise Not_found
let default_dialect = Dialect.create_unknown ~purpose:`Printing ()
let make_pp ?(dialect = default_dialect) ?(subst = empty_subst) () ppf req =
let query = Query.expand subst (req.query dialect) in
Format.fprintf ppf "(%a -->%s %a) {|%a|}"
Row_type.pp req.param_type
(match Row_mult.expose req.row_mult with
| `Zero -> "."
| `One -> ""
| `Zero_or_one -> "?"
| `Zero_or_more -> "*")
Row_type.pp req.row_type
Query.pp query
let pp ppf = make_pp () ppf
let pp_with_param_enabled =
(match Sys.getenv "CAQTI_DEBUG_PARAM" with
| "true" -> true
| "false" -> false
| s ->
Log.err (fun f ->
f "Invalid value %s for CAQTI_DEBUG_PARAM, assuming false." s);
false
| exception Not_found -> false)
let make_pp_with_param ?dialect ?subst () ppf (req, param) =
let pp = make_pp ?subst ?dialect () in
pp ppf req;
if pp_with_param_enabled then
Format.fprintf ppf " %a" (Row.pp req.param_type) param
type liveness_witness = int option
let liveness_witness request =
assert (request.id <> None);
request.id