Dotenv Build Status GitHub tag (latest SemVer)

Dotenv handling for deno.

Usage

Setup a .env file in the root of your project.

# .env
GREETING=hello world

Then import the configuration using the config function.

// app.ts
import { config } from "https://deno.land/x/dotenv/mod.ts";

console.log(config());

Then run your app.

> deno app.ts
{ GREETING: "hello world" }

Options

  • path?: string: Optional path to .env file. Defaults to ./.env.
  • export?: boolean: Set to true to export all .env variables to the current processes environment. Variables are then accessable via deno's env function. Defaults to false.
  • safe?: boolean: Set to true to ensure that all necessary environment variables are defined after reading from .env. It will read .env.example to get the list of needed variables.
  • example?: string: Optional path to .env.example file. Defaults to ./.env.example.
  • allowEmptyValues?: boolean: Set to true to allow required env variables to be empty. Otherwise it will throw an error if any variable is empty. Defaults to false.

Auto loading

load.ts automatically loads the local .env file on import and exports it to the process environment:

# .env
GREETING=hello world
// app.ts
import "https://deno.land/x/dotenv/load.ts";
import { env } from "deno";

console.log(env().GREETING);
> deno --allow-env app.ts
hello world

Safe Mode

To enable safe mode, create a .env.example file in the root of the project.

# .env.example
GREETING=

Then import the configuration with safe option set to true.

// app.ts
import { config } from "https://deno.land/x/dotenv/mod.ts";

console.log(config({ safe: true }));

If any of the defined variables is not in .env, an error will occur. This method is preferred because it prevents runtime errors in a production application due to improper configuration.

Another way to suply required variables is externally, like so:

GREETING="hello world" deno --allow-env app.ts

Parsing Rules

The parsing engine currently supports the following rules:

  • BASIC=basic becomes {BASIC: 'basic'}
  • empty lines are skipped
  • lines beginning with # are treated as comments
  • empty values become empty strings (EMPTY= becomes {EMPTY: ''})
  • single and double quoted values are escaped (SINGLE_QUOTE='quoted' becomes {SINGLE_QUOTE: "quoted"})
  • new lines are expanded if in double quotes (MULTILINE="new\nline" becomes
{MULTILINE: 'new
line'}
  • inner quotes are maintained (think JSON) (JSON={"foo": "bar"} becomes {JSON:"{\"foo\": \"bar\"}")
  • whitespace is removed from both ends of the value (see more on trim) (FOO=" some value " becomes {FOO: 'some value'})

Contributing

Issues and pull requests welcome. Please run make fmt before commiting.

Credit

  • Inspired by the node module dotenv.