Struct Env

pub struct Env(/* private fields */);

Environment variable abstraction

Environment variables are global to a process, and, as such, are difficult to test with a multi- threaded test runner like Rust’s. This enables loading environment variables either from the actual process environment (std::env::var) or from a hash map.

Process environments are cheap to clone:

• Faked process environments are wrapped in an internal Arc
• Real process environments are pointer-sized

Implementations

impl Env

pub fn get(&self, k: &str) -> Result<String, VarError>

Retrieve a value for the given k and return VarError is that key is not present.

pub fn from_slice<'a>(vars: &[(&'a str, &'a str)]) -> Self

Create a fake process environment from a slice of tuples.

Examples

use aws_types::os_shim_internal::Env;
let mock_env = Env::from_slice(&[
    ("HOME", "/home/myname"),
    ("AWS_REGION", "us-west-2")
]);
assert_eq!(mock_env.get("HOME").unwrap(), "/home/myname");

pub fn real() -> Self

Create a process environment that uses the real process environment

Calls will be delegated to std::env::var.

Trait Implementations

impl Clone for Env

fn clone(&self) -> Env

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Env

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for Env

fn default() -> Self

Returns the “default value” for a type.

impl From<HashMap<String, String>> for Env

fn from(hash_map: HashMap<String, String>) -> Self

Converts to this type from the input type.