Templates in controllers

Using templates in controllers typically involves rendering them inside a request handler and returning the result as HTML, for example:

struct Index;

#[async_trait]
impl Controller for Index {
    async fn handle(&self, request: &Request) -> Result<Response, Error> {
        let template = Template::load("templates/index.html")?;
        let ctx = context!("title" => "Home page");
        let rendered = template.render(&ctx)?;

        Ok(Response::new().html(rendered))
    }
}

The template will be loaded from the template cache, rendered with the provided context, and used as a body for a response with the correct Content-Type header.

Since this is a very common way to use templates in controllers, Rwf has the render! macro to make this less verbose:

#[async_trait]
impl Controller for Index {
    async fn handle(&self, request: &Request) -> Result<Response, Error> {
        render!("templates/index.html", "title" => "Home page")
    }
}

The render! macro takes the template path as the first argument, and optionally, a mapping of variable names and values as subsequent arguments. It creates a Response automatically, so there is no need to return one manually.

If the template doesn't have any variables, you can use render! with just the template name:

render!("templates/index.html")