Attribute Macro header

#[header]

Extracts a specific HTTP header into a variable.

This attribute macro retrieves a specific HTTP header by name and makes it available as a variable. Header values are extracted from the request headers collection.

Usage

use hyperlane_macros::*;
use hyperlane::*;

#[header(HOST => host_header)]
async fn handle_with_host(ctx: Context) {
    if let Some(host) = host_header {
        // Use the host header value
    }
}

#[header("Content-Type" => content_type)]
async fn handle_with_content_type(ctx: Context) {
    if let Some(ct) = content_type {
        // Use the content type header
    }
}

The macro accepts a header name-to-variable mapping in the format HEADER_NAME => variable_name or "Header-Name" => variable_name. The variable will be available as an Option<String>.