docker-env

A small Rust utility crate for reading environment variables and Docker-style secrets in containerised applications.

This library is designed for applications running in Docker or Kubernetes environments where secrets may be injected either as environment variables or mounted files.

🔧 Features

• Simple and typed access to environment variables.
• Support for Docker-style secrets via _FILE suffix (e.g., DATABASE_PASSWORD_FILE).
• Fallback to default values or panics for required variables.
• Logs helpful error messages on failure (requires tracing).

📦 Installation

Add to your Cargo.toml:

[dependencies]
docker-env = "0.1"

🚀 Usage

use docker_env::{get_env, get_env_or, get_env_or_panic};

// Read a value as a secret (from a file path in ENV)
let password: String = get_env("DATABASE_PASSWORD", true).unwrap();

// Read with a fallback default
let port: u16 = get_env_or("PORT", 8080, false);

// Panic if missing (e.g., required configuration)
let api_key: String = get_env_or_panic("API_KEY", false);

🔐 Docker Secret Support

If a variable is marked with has_secret = true, docker-env will first attempt to read its corresponding secret file.

For example, if your app expects:

DATABASE_PASSWORD_FILE=/run/secrets/db_password

Then calling:

get_env::<String>("DATABASE_PASSWORD", true);

will load the contents of /run/secrets/db_password.