Don't use Caqti but sqlite3-ocaml

dune-project

@@ -25,9 +25,6 @@
   (alcotest :with-test)
   (ocamlformat
    (= 0.26.0))
-  caqti
-  caqti-driver-sqlite3
-  caqti-lwt
   csv
   dream
   dune
@@ -41,6 +38,7 @@
   ppx_deriving
   (ppx_yojson_conv
    (<= v0.15.1))
+  sqlite3
   yojson))
 
 (using menhir 2.1)

lib/command.ml

@@ -1,5 +1,4 @@
 open Util
-open Lwt.Infix
 
 let to_json filename =
   match Parser.parse_file filename with
@@ -21,8 +20,7 @@ let check filename =
   try
     let m, notes = Loader.load_file filename in
     match
-      Lwt_main.run
-        (Sql_writer.dump_on_memory m >>= fun con -> Verifier.verify con notes)
+      Sql_writer.dump_on_memory m |> fun con -> Verifier.verify con notes
     with
     | Ok () ->
         Printf.printf "%d accounts\n%d transactions\n" (List.length m.accounts)
@@ -32,14 +30,8 @@ let check filename =
 
 let dump in_filename out_filename =
   let m, _ = Loader.load_file in_filename in
-  Lwt_main.run
-  @@
-  let%lwt _ =
-    Sql_writer.dump
-      ("sqlite3://" ^ Filename.concat (Sys.getcwd ()) out_filename)
-      m
-  in
-  Lwt.return_unit
+  let filepath = Filename.concat (Sys.getcwd ()) out_filename in
+  Sql_writer.dump filepath m |> ignore
 
 let serve =
   let interface, port =

lib/datastore.ml

@@ -0,0 +1,41 @@
+type connection = Sqlite3.db
+type prepared_stmt = Sqlite3.stmt
+type value = Int of int | Text of string | Null
+
+let value_of_sqlite3_data = function
+  | Sqlite3.Data.INT i -> Int (Int64.to_int i)
+  | Sqlite3.Data.TEXT s -> Text s
+  | Sqlite3.Data.NULL -> Null
+  | _ -> failwith "value_of_sqlite3_data: Invalid datatype"
+
+let sqlite3_data_of_value = function
+  | Int i -> Sqlite3.Data.INT (Int64.of_int i)
+  | Text s -> Sqlite3.Data.TEXT s
+  | Null -> Sqlite3.Data.NULL
+
+let in_memory_database = ":memory:"
+let connect path = Sqlite3.db_open path
+let disconnect con = Sqlite3.db_close con |> ignore
+let prepare conn sql = Sqlite3.prepare conn sql
+
+exception Sqlite_error of string
+
+let raise_if_not_success rc =
+  if Sqlite3.Rc.is_success rc then ()
+  else raise (Sqlite_error (Sqlite3.Rc.to_string rc))
+
+let query stmt values =
+  try
+    Sqlite3.reset stmt |> raise_if_not_success;
+    values
+    |> List.map sqlite3_data_of_value
+    |> Sqlite3.bind_values stmt |> raise_if_not_success;
+    let result, rows =
+      Sqlite3.fold stmt ~init:[] ~f:(fun acc row ->
+          (Array.to_list row |> List.map value_of_sqlite3_data) :: acc)
+    in
+    raise_if_not_success result;
+    Ok (List.rev rows)
+  with Sqlite_error msg -> Error msg
+
+let execute stmt values = query stmt values |> Result.map (fun _ -> ())

lib/datastore.mli

@@ -0,0 +1,10 @@
+type connection
+type prepared_stmt
+type value = Int of int | Text of string | Null
+
+val in_memory_database : string
+val connect : string -> connection
+val disconnect : connection -> unit
+val prepare : connection -> string -> prepared_stmt
+val execute : prepared_stmt -> value list -> (unit, string) result
+val query : prepared_stmt -> value list -> (value list list, string) result

lib/dune

@@ -9,12 +9,4 @@
  (name qash)
  (preprocess
   (pps lwt_ppx ppx_deriving.make ppx_deriving.show ppx_yojson_conv))
- (libraries
-  caqti-driver-sqlite3
-  caqti-lwt
-  cmdliner
-  csv
-  dream
-  fsnotify
-  logs.fmt
-  pcre))
+ (libraries cmdliner csv dream fsnotify logs.fmt pcre sqlite3))