Struct EnvHandler 

pub struct EnvHandler<'a> { /* private fields */ }

A handler for retrieving values from environment variables.

This struct is responsible for handling requests by checking for the existence of an environment variable corresponding to the provided key. If the environment variable is not found, it delegates the request to the next handler (if provided).

Examples

use cor_args::{EnvHandler, Handler};

// Create a new EnvHandler specifying a prefix for environment variables
let handler = EnvHandler::new().prefix("MYAPP_");

// Add a fallback handler
//let handler = handler.next(some_other_handler.into());

// Handle a configuration request matching `MYAPP_some_key`
let value = handler.handle_request("some_key");

Implementations

impl<'a> EnvHandler<'a>

pub fn new() -> Self

Creates a new EnvHandler.

Arguments

• prefix - An optional prefix to which requests will prepend when handle_request() is executed.IfNone`, an empty string is assigned.

Examples

use cor_args::EnvHandler;

let handler = EnvHandler::new();

pub fn next(self, handler: Box<dyn Handler>) -> Self

pub fn prefix<S>(self, prefix: S) -> Self

where S: Into<Cow<'a, str>>,

Trait Implementations

impl<'a> Handler for EnvHandler<'a>

fn handle_request(&self, key: &str) -> Option<String>

Retrieves a value for the specified key from the environment variables.

If the environment variable corresponding to the key is not found, and if a next handler is provided, it delegates the request to the next handler. If there’s no next handler or if the key is not found both in the environment and the next handler, it returns None.

Arguments

• key - The key for which the value needs to be retrieved from environment variables.

Returns

An Option containing the value associated with the key, or None if the key is not found.

impl<'a> Into<Box<dyn Handler + 'a>> for EnvHandler<'a>

fn into(self) -> Box<dyn Handler + 'a>

Converts this type into the (usually inferred) input type.