Struct trillium_api::ApiHandler

pub struct ApiHandler<F, BodyType> { /* private fields */ }

Trillium API handler

Construct with api or ApiHandler::new and an async function that takes a [Conn] and any type that you’ve defined which implements DeserializeOwned and returns the [Conn].

Examples

use trillium_api::{ApiHandler, ApiConnExt};
use serde::{Serialize, Deserialize};

#[derive(Serialize, Deserialize)]
struct BlogPost {
    title: String,
    body: String,
}

async fn blog_post_handler(conn: trillium::Conn, mut blog_post: BlogPost) -> trillium::Conn {
    match persist(&mut blog_post).await {
        Ok(_) => conn.with_json(&blog_post),
        Err(_) => conn.with_json(&blog_post).with_status(406),
    }
}

let handler = ApiHandler::new(blog_post_handler); // equivalently, api(blog_post_handler)

/// accepts json
assert_ok!(
    post("/")
        .with_request_body(r#"{ "title": "introducing trillium.rs", "body": "it's like plug, for async rust" }"#)
        .with_request_header("content-type", "application/json")
        .on(&handler),
    "{\"title\":\"introducing trillium.rs\",\"body\":\"it's like plug, for async rust\"}",
    "content-type" => "application/json"
);


/// accepts x-www-form-urlencoded
assert_ok!(
    post("/")
        .with_request_body(r#"title=introducing+trillium.rs&body=it%27s+like+plug%2C+for+async+rust"#)
        .with_request_header("content-type", "application/x-www-form-urlencoded")
        .on(&handler),
    "{\"title\":\"introducing trillium.rs\",\"body\":\"it's like plug, for async rust\"}",
    "content-type" => "application/json"
);

Implementations

impl<F, Fut, BodyType> ApiHandler<F, BodyType>where
    BodyType: DeserializeOwned + Send + Sync + 'static,
    F: Fn(Conn, BodyType) -> Fut + Send + Sync + 'static,
    Fut: Future<Output = Conn> + Send + 'static,

pub fn new(handler_fn: F) -> Self

Build a new API handler for the given async function. This is aliased as api.

Trait Implementations

impl<F: Debug, BodyType: Debug> Debug for ApiHandler<F, BodyType>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<F: Default, BodyType: Default> Default for ApiHandler<F, BodyType>

fn default() -> ApiHandler<F, BodyType>

Returns the “default value” for a type.

impl<F, Fut, BodyType> Handler for ApiHandler<F, BodyType>where
    BodyType: DeserializeOwned + Send + Sync + 'static,
    F: Fn(Conn, BodyType) -> Fut + Send + Sync + 'static,
    Fut: Future<Output = Conn> + Send + 'static,

fn run<'life0, 'async_trait>(
    &'life0 self,
    conn: Conn
) -> Pin<Box<dyn Future<Output = Conn> + Send + 'async_trait>>where
    'life0: 'async_trait,
    Self: 'async_trait,

Executes this handler, performing any modifications to the Conn that are desired.

fn init<'life0, 'life1, 'async_trait>(
    &'life0 mut self,
    _info: &'life1 mut Info
) -> Pin<Box<dyn Future<Output = ()> + Send + 'async_trait, Global>>where
    'life0: 'async_trait,
    'life1: 'async_trait,
    Self: 'async_trait,

Performs one-time async set up on a mutable borrow of the Handler before the server starts accepting requests. This allows a Handler to be defined in synchronous code but perform async setup such as establishing a database connection or fetching some state from an external source. This is optional, and chances are high that you do not need this.

fn before_send<'life0, 'async_trait>(
    &'life0 self,
    conn: Conn
) -> Pin<Box<dyn Future<Output = Conn> + Send + 'async_trait, Global>>where
    'life0: 'async_trait,
    Self: 'async_trait,

Performs any final modifications to this conn after all handlers have been run. Although this is a slight deviation from the simple conn->conn->conn chain represented by most Handlers, it provides an easy way for libraries to effectively inject a second handler into a response chain. This is useful for loggers that need to record information both before and after other handlers have run, as well as database transaction handlers and similar library code.

fn has_upgrade(&self, _upgrade: &Upgrade<BoxedTransport>) -> bool

predicate function answering the question of whether this Handler would like to take ownership of the negotiated Upgrade. If this returns true, you must implement [Handler::upgrade]. The first handler that responds true to this will receive ownership of the [trillium::Upgrade][crate::Upgrade] in a subsequent call to [Handler::upgrade]

fn upgrade<'life0, 'async_trait>(
    &'life0 self,
    _upgrade: Upgrade<BoxedTransport>
) -> Pin<Box<dyn Future<Output = ()> + Send + 'async_trait, Global>>where
    'life0: 'async_trait,
    Self: 'async_trait,

This will only be called if the handler reponds true to [Handler::has_upgrade] and will only be called once for this upgrade. There is no return value, and this function takes exclusive ownership of the underlying transport once this is called. You can downcast the transport to whatever the source transport type is and perform any non-http protocol communication that has been negotiated. You probably don’t want this unless you’re implementing something like websockets. Please note that for many transports such as TcpStreams, dropping the transport (and therefore the Upgrade) will hang up / disconnect.

fn name(&self) -> Cow<'static, str>

Customize the name of your handler. This is used in Debug implementations. The default is the type name of this handler.