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

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§

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impl<'a> Metadata<'a>

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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");
}
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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§

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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.

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type Error = ()

The associated error to be returned if derivation fails.
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fn from_request(request: &'a Request<'_>) -> Outcome<Self, ()>

Derives an instance of Self from the incoming request metadata. Read more

Auto Trait Implementations§

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impl<'a> Freeze for Metadata<'a>

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impl<'a> RefUnwindSafe for Metadata<'a>

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impl<'a> Send for Metadata<'a>

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impl<'a> Sync for Metadata<'a>

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impl<'a> Unpin for Metadata<'a>

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impl<'a> UnwindSafe for Metadata<'a>

Blanket Implementations§

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impl<T> Any for T
where T: 'static + ?Sized,

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fn type_id(&self) -> TypeId

Gets the TypeId of self. Read more
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impl<T, I> AsResult<T, I> for T
where I: Input,

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fn as_result(self) -> Result<T, ParseErr<I>>

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impl<T> Borrow<T> for T
where T: ?Sized,

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fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more
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impl<T> BorrowMut<T> for T
where T: ?Sized,

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fn borrow_mut(&mut self) -> &mut T

Mutably borrows from an owned value. Read more
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impl<T> From<T> for T

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fn from(t: T) -> T

Returns the argument unchanged.

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impl<T, U> Into<U> for T
where U: From<T>,

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fn into(self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

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impl<T> IntoCollection<T> for T

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fn into_collection<A>(self) -> SmallVec<A>
where A: Array<Item = T>,

Converts self into a collection.
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fn mapped<U, F, A>(self, f: F) -> SmallVec<A>
where F: FnMut(T) -> U, A: Array<Item = U>,

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impl<T> IntoSql for T

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fn into_sql<T>(self) -> Self::Expression
where Self: AsExpression<T> + Sized,

Convert self to an expression for Diesel’s query builder. Read more
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fn as_sql<'a, T>(&'a self) -> <&'a Self as AsExpression<T>>::Expression

Convert &self to an expression for Diesel’s query builder. Read more
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impl<T> Same for T

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type Output = T

Should always be Self
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impl<T, U> TryFrom<U> for T
where U: Into<T>,

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type Error = Infallible

The type returned in the event of a conversion error.
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fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>

Performs the conversion.
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impl<T, U> TryInto<U> for T
where U: TryFrom<T>,

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type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.
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fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

Performs the conversion.
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impl<T, U> TryInto<U> for T
where U: TryFrom<T>,

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type Err = <U as TryFrom<T>>::Err

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fn try_into(self) -> Result<U, <U as TryFrom<T>>::Err>

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impl<T> Typeable for T
where T: Any,

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fn get_type(&self) -> TypeId

Get the TypeId of this object.
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impl<V, T> VZip<V> for T
where V: MultiLane<T>,

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fn vzip(self) -> V