alux_http_rocket/
handler.rs

1//! Reaches one endpoint: it reads the arguments its roles state, applies the operation, and answers.
2
3use crate::RocketAnswer;
4use crate::input::{
5    RocketBodyInput, RocketCookieInput, RocketFormInput, RocketHeadInput, RocketHeaderInput, RocketInputsAlg,
6    RocketMultipartInput, RocketPathInput, RocketQueryInput, RocketRawBodyInput,
7};
8use crate::route::{RocketEndpoint, RocketRoute, RocketRouteImpl, RocketSelector};
9use alux_ext::{ApplyAlg, HandlerContextAlg, OperationAlg};
10use alux_http::{
11    HandlerAlg, HandlerEndpointAlg, HttpErrorAlg, HttpInputAlg, HttpMethod, HttpSelectorAlg, OutputAlg, OutputKindAlg,
12    RouteAlg, RoutePath, SelectorAlg,
13};
14use std::sync::Arc;
15
16/// Interprets typed HTTP programs as executable Rocket routes.
17pub struct RocketHandlerImpl<Context> {
18    context: Arc<Context>,
19}
20
21impl<Context> RocketHandlerImpl<Context> {
22    /// Creates an interpreter owning a newly shared context.
23    pub fn new(context: Context) -> Self {
24        Self { context: Arc::new(context) }
25    }
26
27    /// Creates an interpreter from an existing shared context.
28    pub fn from_shared(context: Arc<Context>) -> Self {
29        Self { context }
30    }
31}
32
33impl<Context> HandlerContextAlg<Context> for RocketHandlerImpl<Context>
34where
35    Context: Send + Sync + 'static,
36{
37    type Handle = Arc<Context>;
38}
39
40impl<Context> HandlerAlg for RocketHandlerImpl<Context> {
41    type Endpoint = RocketEndpoint;
42}
43
44impl<Context> HttpInputAlg for RocketHandlerImpl<Context> {
45    type Path<I> = RocketPathInput<I>;
46    type Query<I> = RocketQueryInput<I>;
47    type Body<I> = RocketBodyInput<I>;
48    type Form<I> = RocketFormInput<I>;
49    type Multipart<I> = RocketMultipartInput<I>;
50    type RawBody<I> = RocketRawBodyInput<I>;
51    // Rocket reads a header, an authentication value, and an endpoint context from the headers.
52    type Header<I> = RocketHeaderInput<I>;
53    type Cookie<I> = RocketCookieInput<I>;
54    type Auth<I> = RocketHeaderInput<I>;
55    type Context<I> = RocketHeadInput<I>;
56}
57
58impl<Context, Inputs, Args, Transform, Answering, Output>
59    HandlerEndpointAlg<Arc<Context>, Inputs, Args, Transform, Output> for RocketHandlerImpl<Context>
60where
61    Context: Send + Sync + 'static,
62    Inputs: RocketInputsAlg<Args> + Send + 'static,
63    Args: Send + 'static,
64    Output: Send + 'static,
65    Transform: OutputKindAlg<Self, Output, Transform = Answering> + Send + 'static,
66    Answering: OutputAlg<Output, Output = RocketAnswer>,
67{
68    fn finish_handler<Handler>(&self, handler: Handler) -> <Self as HandlerAlg>::Endpoint
69    where
70        Handler: OperationAlg + ApplyAlg<Arc<Context>, Args, Output = Output> + Send + Sync + 'static,
71    {
72        let context = Arc::clone(&self.context);
73        let handler = Arc::new(handler);
74
75        RocketEndpoint::new(move |request| {
76            let context = Arc::clone(&context);
77            let handler = Arc::clone(&handler);
78            Box::pin(async move {
79                let inputs = match Inputs::extract(&request).await {
80                    Ok(inputs) => inputs,
81                    Err(error) => return unreadable(&error),
82                };
83                let output = handler.apply(context, inputs).await;
84
85                Answering::output(output)
86            })
87        })
88    }
89}
90
91/// Answers with what reading a request meant when it could not be read.
92fn unreadable(error: &impl HttpErrorAlg) -> RocketAnswer {
93    RocketAnswer::content(error.http_status(), "text/plain; charset=utf-8", error.http_message())
94}
95
96impl<Context> SelectorAlg for RocketHandlerImpl<Context> {
97    type Selector = RocketSelector;
98
99    fn identity(&self) -> Self::Selector {
100        SelectorAlg::identity(&RocketRouteImpl)
101    }
102
103    fn compose(&self, first: Self::Selector, second: Self::Selector) -> Self::Selector {
104        SelectorAlg::compose(&RocketRouteImpl, first, second)
105    }
106}
107
108impl<Context> RouteAlg for RocketHandlerImpl<Context> {
109    type Route = RocketRoute;
110    type Selector = RocketSelector;
111    type Endpoint = RocketEndpoint;
112
113    fn initial(&self) -> Self::Route {
114        RouteAlg::initial(&RocketRouteImpl)
115    }
116
117    fn coproduct(&self, left: Self::Route, right: Self::Route) -> Self::Route {
118        RouteAlg::coproduct(&RocketRouteImpl, left, right)
119    }
120
121    fn precompose(&self, selector: Self::Selector, route: Self::Route) -> Self::Route {
122        RouteAlg::precompose(&RocketRouteImpl, selector, route)
123    }
124
125    fn lift(&self, endpoint: Self::Endpoint) -> Self::Route {
126        RouteAlg::lift(&RocketRouteImpl, endpoint)
127    }
128}
129
130impl<Context> HttpSelectorAlg for RocketHandlerImpl<Context> {
131    type Selector = RocketSelector;
132
133    fn http_method(&self, method: HttpMethod) -> Self::Selector {
134        HttpSelectorAlg::http_method(&RocketRouteImpl, method)
135    }
136
137    fn http_path(&self, path: &RoutePath) -> Self::Selector {
138        HttpSelectorAlg::http_path(&RocketRouteImpl, path)
139    }
140
141    fn http_prefix(&self, prefix: &RoutePath) -> Self::Selector {
142        HttpSelectorAlg::http_prefix(&RocketRouteImpl, prefix)
143    }
144}
alux_http_rocket/handler.rs

alux_http_rocket/
handler.rs
