package oenv

Oenv

A composeable environment variable reader for OCaml

Example

let ( let* ) m k = Result.bind in
let* debug = Oenv.(bool "DEBUG" |> read) in
let* api_key = Oenv.(string "API_KEY" |> read) in
Printf.printf "settigns: debug: %b, api_key: %s\n" debug api_key;
Result.ok ()

Features

• Basic types: string, int, bool
• 2nd types: list, option
• Product
• Custom types
• Logs support

Product

Product creates product reader.

type t =
  { name : string
  ; value : string option
  }
let make name value = { name; value }

let t = Oenv.(Product.v make
  +: string "NAME"
  +: string "VALUE" |> option
  |> close)

Oenv.read t

Custom types

Make custom type reader with custom combinator.

type flag = A | B
let of_string = function
  | "A" -> Ok A
  | "B" -> Ok B
  | other -> Error (`Parse ("flag", other))

let flag = Oenv.custom ~secret:false "FLAG" of_string

See ./examples and reference for more details.