main

Main function attribute for a Compute program.

Usage

This attribute should be applied to a main function that takes a request and returns a response or an error. For example:

use fastly::{Error, Request, Response};

#[fastly::main]
fn main(ds_req: Request) -> Result<Response, Error> {
    Ok(ds_req.send("example_backend")?)
}

You can apply #[fastly::main] to any function that takes Request as its sole argument, and returns a Result<Response, Error>.

More Information

This is a convenience to abstract over the common usage of Request::from_client() and Response::send_to_client() at the beginning and end of a program's main() function. The macro use above is equivalent to the following code:

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use fastly::{Error, Request};

fn main() -> Result<(), Error> {
    let ds_req = Request::from_client();
    let us_resp = ds_req.send("example_backend")?;
    us_resp.send_to_client();
    Ok(())
}