Struct rocket::fairing::AdHoc

pub struct AdHoc { /* private fields */ }

A ad-hoc fairing that can be created from a function or closure.

This enum can be used to create a fairing from a simple function or closure without creating a new structure or implementing Fairing directly.

Usage

Use the on_attach, on_launch, on_request, or on_response constructors to create an AdHoc structure from a function or closure. Then, simply attach the structure to the Rocket instance.

Example

The following snippet creates a Rocket instance with two ad-hoc fairings. The first, a launch fairing named “Launch Printer”, simply prints a message indicating that the application is about to the launch. The second named “Put Rewriter”, a request fairing, rewrites the method of all requests to be PUT.

use rocket::fairing::AdHoc;
use rocket::http::Method;

rocket::ignite()
    .attach(AdHoc::on_launch("Launch Printer", |_| {
        println!("Rocket is about to launch! Exciting! Here we go...");
    }))
    .attach(AdHoc::on_request("Put Rewriter", |req, _| {
        req.set_method(Method::Put);
    }));

Implementations

impl AdHoc

pub fn on_attach<F>(name: &'static str, f: F) -> AdHoc where
    F: FnOnce(Rocket) -> Result<Rocket, Rocket> + Send + 'static, 

Constructs an AdHoc attach fairing named name. The function f will be called by Rocket when this fairing is attached.

Example

use rocket::fairing::AdHoc;

// The no-op attach fairing.
let fairing = AdHoc::on_attach("No-Op", |rocket| Ok(rocket));

pub fn on_launch<F>(name: &'static str, f: F) -> AdHoc where
    F: FnOnce(&Rocket) + Send + 'static, 

Constructs an AdHoc launch fairing named name. The function f will be called by Rocket just prior to launching.

Example

use rocket::fairing::AdHoc;

// A fairing that prints a message just before launching.
let fairing = AdHoc::on_launch("Launch Count", |rocket| {
    println!("Launching in T-3..2..1..");
});

pub fn on_request<F>(name: &'static str, f: F) -> AdHoc where
    F: Fn(&mut Request<'_>, &Data) + Send + Sync + 'static, 

Constructs an AdHoc request fairing named name. The function f will be called by Rocket when a new request is received.

Example

use rocket::fairing::AdHoc;

// The no-op request fairing.
let fairing = AdHoc::on_request("Dummy", |req, data| {
    // do something with the request and data...
});

pub fn on_response<F>(name: &'static str, f: F) -> AdHoc where
    F: Fn(&Request<'_>, &mut Response<'_>) + Send + Sync + 'static, 

Constructs an AdHoc response fairing named name. The function f will be called by Rocket when a response is ready to be sent.

Example

use rocket::fairing::AdHoc;

// The no-op response fairing.
let fairing = AdHoc::on_response("Dummy", |req, resp| {
    // do something with the request and pending response...
});

Trait Implementations

impl Fairing for AdHoc

fn info(&self) -> Info

Returns an Info structure containing the name and Kind of this fairing. The name can be any arbitrary string. Kind must be an ord set of Kind variants.

fn on_attach(&self, rocket: Rocket) -> Result<Rocket, Rocket>

The attach callback. Returns Ok if launch should proceed and Err if launch should be aborted.

fn on_launch(&self, rocket: &Rocket)

The launch callback.

fn on_request(&self, request: &mut Request<'_>, data: &Data)

The request callback.

fn on_response(&self, request: &Request<'_>, response: &mut Response<'_>)

The response callback.