response.rs

fn main() {
    lambda::gateway::start(|req| {
        //...

        let encoded_thumbnail = encode_png_image(thumbnail)?;
        let encoded_thumbnail = base64::encode(&encoded_thumbnail);

        let res = lambda::gateway::response() // Create a response
            .status(200) // Set HTTP status code as 200 (Ok)
            .body(lambda::gateway::Body::from(encoded_thumbnail))?; // Convert the encoded_thumbnail to 

        Ok(res)
    })
}