1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178

//! Validation for the [garde](https://docs.rs/garde/latest/garde) crate.
//! Requires the `garde` feature flag

use ::garde::Validate;
use actix_web::dev::{ServiceFactory, ServiceRequest};
use actix_web::http::StatusCode;
use actix_web::FromRequest;
use actix_web::{App, HttpRequest, HttpResponse, ResponseError};
use futures_core::ready;
use futures_core::Future;
use std::fmt::Display;
use std::sync::Arc;
use std::{fmt::Debug, ops::Deref, pin::Pin, task::Poll};
use thiserror::Error;

/// A validated extactor.
///
/// This type will run any validations on the inner extractors.
///
/// ```
/// use actix_web::{post, web::{self, Json}, App};
/// use serde::Deserialize;
/// use garde::Validate;
///
/// #[derive(Deserialize, Validate)]
/// struct Info {
///     #[garde(length(min = 3))]
///     username: String,
/// }
///
/// #[post("/")]
/// async fn index(info: Validated<Json<Info>>) -> String {
///     format!("Welcome {}!", info.username)
/// }
/// ```
pub struct Validated<T>(pub T);

impl<T> Validated<T> {
    pub fn into_inner(self) -> T {
        self.0
    }
}

impl<T> std::ops::Deref for Validated<T> {
    type Target = T;

    fn deref(&self) -> &Self::Target {
        &self.0
    }
}

impl<T> std::ops::DerefMut for Validated<T> {
    fn deref_mut(&mut self) -> &mut Self::Target {
        &mut self.0
    }
}

pub struct ValidatedFut<T: FromRequest> {
    req: actix_web::HttpRequest,
    fut: <T as FromRequest>::Future,
    error_handler: Option<GardeErrHandler>,
}

impl<T> Future for ValidatedFut<T>
where
    T: FromRequest + Debug + Deref,
    T::Future: Unpin,
    T::Target: Validate,
    <T::Target as garde::Validate>::Context: Default,
{
    type Output = Result<Validated<T>, actix_web::Error>;

    fn poll(
        self: std::pin::Pin<&mut Self>,
        cx: &mut std::task::Context<'_>,
    ) -> std::task::Poll<Self::Output> {
        let this = self.get_mut();
        let res = ready!(Pin::new(&mut this.fut).poll(cx));

        let res = match res {
            Ok(data) => {
                if let Err(e) = data.validate() {
                    if let Some(error_handler) = &this.error_handler {
                        Err((*error_handler)(e, &this.req))
                    } else {
                        let err: Error = e.into();
                        Err(err.into())
                    }
                } else {
                    Ok(Validated(data))
                }
            }
            Err(e) => Err(e.into()),
        };

        Poll::Ready(res)
    }
}

impl<T> FromRequest for Validated<T>
where
    T: FromRequest + Debug + Deref,
    T::Future: Unpin,
    T::Target: Validate,
    <T::Target as garde::Validate>::Context: Default,
{
    type Error = actix_web::Error;

    type Future = ValidatedFut<T>;

    fn from_request(
        req: &actix_web::HttpRequest,
        payload: &mut actix_web::dev::Payload,
    ) -> Self::Future {
        let error_handler = req
            .app_data::<GardeErrorHandler>()
            .map(|h| h.handler.clone());

        let fut = T::from_request(req, payload);

        ValidatedFut {
            fut,
            error_handler,
            req: req.clone(),
        }
    }
}

#[derive(Error, Debug)]
struct Error {
    report: garde::Report,
}

impl From<garde::Report> for Error {
    fn from(value: garde::Report) -> Self {
        Self { report: value }
    }
}

impl Display for Error {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        write!(f, "{}", self.report)
    }
}

impl ResponseError for Error {
    fn error_response(&self) -> HttpResponse {
        let message = self
            .report
            .iter()
            .map(|(path, error)| format!("{}: {}", path.to_string(), error.message().to_string()))
            .collect::<Vec<_>>()
            .join("\n");

        HttpResponse::build(StatusCode::BAD_REQUEST)
            .body(format!("Validation errors in fields:\n{}", message))
    }
}

pub type GardeErrHandler =
    Arc<dyn Fn(garde::Report, &HttpRequest) -> actix_web::Error + Send + Sync>;

struct GardeErrorHandler {
    handler: GardeErrHandler,
}

pub trait GardeErrorHandlerExt {
    fn garde_error_handler(self, handler: GardeErrHandler) -> Self;
}

impl<T> GardeErrorHandlerExt for App<T>
where
    T: ServiceFactory<ServiceRequest, Config = (), Error = actix_web::Error, InitError = ()>,
{
    fn garde_error_handler(self, handler: GardeErrHandler) -> Self {
        self.app_data(GardeErrorHandler { handler })
    }
}