environment decoder

Deno package to decode environment variables.

Usage

Import the decodeEnvironment function and call it with an object that defines which decoder to use for each of your environment variables. For example:

import {
  decodeEnvironment,
  asBoolean,
  asString,
  asNumber,
  asStringUnion,
} from "https://deno.land/x/environment-decoder";

const myEnv = decodeEnvironment({
  BASE_URL: asString, // myEnv.BASE_URL will have type 'string'
  ENVIRONMENT: asStringUnion("dev", "qa", "prod"), // myEnv.ENVIRONMENT will have type '"dev" | "qa" | "prod"'
  PORT: asNumber, // myEnv.PORT will have type 'number'
  FEATURE_FLAG: asBoolean, // myEnv.FEATURE_FLAG will have type 'boolean'
  OPTIONAL_FLAG: asString.withDefault("OPTION_1"), // use `.withDefault()` to set default values for non-required environment variables.
});

Notes

environment-decoder will throw an exception when:

environment variables are not set and not using .withDefault()
environment variables cannot be cast to the requested type (for example, using asNumber on abcde)
using asStringUnion or asNumberUnion and the environment variable is not set to one of the allowed values