Struct Metadata

pub struct Metadata<'a>(/* private fields */);

Request guard for dynamiclly querying template metadata.

Usage

The Metadata type implements Rocket’s FromRequest trait, so it can be used as a request guard in any request handler.

use rocket_contrib::templates::{Template, Metadata};

#[get("/")]
fn homepage(metadata: Metadata) -> Template {
    // Conditionally render a template if it's available.
    if metadata.contains_template("some-template") {
        Template::render("some-template", &context)
    } else {
        Template::render("fallback", &context)
    }
}


fn main() {
    rocket::ignite()
        .attach(Template::fairing())
        // ...
}

Implementations

impl<'a> Metadata<'a>

pub fn contains_template(&self, name: &str) -> bool

Returns true if the template with the given name is currently loaded. Otherwise, returns false.

Example

use rocket_contrib::templates::Metadata;

#[get("/")]
fn handler(metadata: Metadata) {
    // Returns `true` if the template with name `"name"` was loaded.
    let loaded = metadata.contains_template("name");
}

pub fn reloading(&self) -> bool

Returns true if template reloading is enabled.

Example

use rocket_contrib::templates::Metadata;

#[get("/")]
fn handler(metadata: Metadata) {
    // Returns `true` if template reloading is enabled.
    let reloading = metadata.reloading();
}

Trait Implementations

impl<'a, 'r> FromRequest<'a, 'r> for Metadata<'a>

Retrieves the template metadata. If a template fairing hasn’t been attached, an error is printed and an empty Err with status InternalServerError (500) is returned.

type Error = ()

The associated error to be returned if derivation fails.

fn from_request(request: &'a Request<'_>) -> Outcome<Self, ()>

Derives an instance of Self from the incoming request metadata.