Attribute Macro request_header 

#[request_header]

Extracts a specific HTTP request header into a variable with panic on missing value.

This attribute macro retrieves a specific HTTP request header by name and makes it available as a variable. Header values are extracted from the request request headers collection. If the requested header does not exist, the function will panic with an error message.

Usage

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

#[route("/request_header")]
struct RequestHeader;

impl ServerHook for RequestHeader {
    async fn new(_ctx: &Context) -> Self {
        Self
    }

    #[prologue_macros(
        request_header(HOST => request_header),
        response_body(&format!("request header: {request_header}")),
        send
    )]
    async fn handle(self, ctx: &Context) {}
}

impl RequestHeader {
    #[request_header(HOST => request_header)]
    async fn request_header_with_ref_self(&self, ctx: &Context) {}
}

#[request_header(HOST => request_header)]
async fn standalone_request_header_handler(ctx: &Context) {}

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

Panics

This macro will panic if the requested header does not exist in the HTTP request headers.