logo
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
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
//! Types representing various errors that can occur in a Rocket application.

use std::{io, fmt};
use std::sync::{Arc, atomic::{Ordering, AtomicBool}};
use std::error::Error as StdError;

use yansi::Paint;
use figment::Profile;

use crate::{Rocket, Orbit};

/// An error that occurs during launch.
///
/// An `Error` is returned by [`launch()`](Rocket::launch()) when launching an
/// application fails or, more rarely, when the runtime fails after lauching.
///
/// # Panics
///
/// A value of this type panics if it is dropped without first being inspected.
/// An _inspection_ occurs when any method is called. For instance, if
/// `println!("Error: {}", e)` is called, where `e: Error`, the `Display::fmt`
/// method being called by `println!` results in `e` being marked as inspected;
/// a subsequent `drop` of the value will _not_ result in a panic. The following
/// snippet illustrates this:
///
/// ```rust
/// # let _ = async {
/// if let Err(error) = rocket::build().launch().await {
///     // This println "inspects" the error.
///     println!("Launch failed! Error: {}", error);
///
///     // This call to drop (explicit here for demonstration) will do nothing.
///     drop(error);
/// }
/// # };
/// ```
///
/// When a value of this type panics, the corresponding error message is pretty
/// printed to the console. The following illustrates this:
///
/// ```rust
/// # let _ = async {
/// let error = rocket::build().launch().await;
///
/// // This call to drop (explicit here for demonstration) will result in
/// // `error` being pretty-printed to the console along with a `panic!`.
/// drop(error);
/// # };
/// ```
///
/// # Usage
///
/// An `Error` value should usually be allowed to `drop` without inspection.
/// There are at least two exceptions:
///
///   1. If you are writing a library or high-level application on-top of
///      Rocket, you likely want to inspect the value before it drops to avoid a
///      Rocket-specific `panic!`. This typically means simply printing the
///      value.
///
///   2. You want to display your own error messages.
pub struct Error {
    handled: AtomicBool,
    kind: ErrorKind
}

/// The kind error that occurred.
///
/// In almost every instance, a launch error occurs because of an I/O error;
/// this is represented by the `Io` variant. A launch error may also occur
/// because of ill-defined routes that lead to collisions or because a fairing
/// encountered an error; these are represented by the `Collision` and
/// `FailedFairing` variants, respectively.
#[derive(Debug)]
#[non_exhaustive]
pub enum ErrorKind {
    /// Binding to the provided address/port failed.
    Bind(io::Error),
    /// An I/O error occurred during launch.
    Io(io::Error),
    /// A valid [`Config`](crate::Config) could not be extracted from the
    /// configured figment.
    Config(figment::Error),
    /// Route collisions were detected.
    Collisions(crate::router::Collisions),
    /// Launch fairing(s) failed.
    FailedFairings(Vec<crate::fairing::Info>),
    /// Sentinels requested abort.
    SentinelAborts(Vec<crate::sentinel::Sentry>),
    /// The configuration profile is not debug but not secret key is configured.
    InsecureSecretKey(Profile),
    /// Shutdown failed.
    Shutdown(
        /// The instance of Rocket that failed to shutdown.
        Arc<Rocket<Orbit>>,
        /// The error that occurred during shutdown, if any.
        Option<Box<dyn StdError + Send + Sync>>
    ),
}

impl From<ErrorKind> for Error {
    fn from(kind: ErrorKind) -> Self {
        Error::new(kind)
    }
}

impl Error {
    #[inline(always)]
    pub(crate) fn new(kind: ErrorKind) -> Error {
        Error { handled: AtomicBool::new(false), kind }
    }

    #[inline(always)]
    pub(crate) fn shutdown<E>(rocket: Arc<Rocket<Orbit>>, error: E) -> Error
        where E: Into<Option<crate::http::hyper::Error>>
    {
        let error = error.into().map(|e| Box::new(e) as Box<dyn StdError + Sync + Send>);
        Error::new(ErrorKind::Shutdown(rocket, error))
    }

    #[inline(always)]
    fn was_handled(&self) -> bool {
        self.handled.load(Ordering::Acquire)
    }

    #[inline(always)]
    fn mark_handled(&self) {
        self.handled.store(true, Ordering::Release)
    }

    /// Retrieve the `kind` of the launch error.
    ///
    /// # Example
    ///
    /// ```rust
    /// use rocket::error::ErrorKind;
    ///
    /// # let _ = async {
    /// if let Err(error) = rocket::build().launch().await {
    ///     match error.kind() {
    ///         ErrorKind::Io(e) => println!("found an i/o launch error: {}", e),
    ///         e => println!("something else happened: {}", e)
    ///     }
    /// }
    /// # };
    /// ```
    #[inline]
    pub fn kind(&self) -> &ErrorKind {
        self.mark_handled();
        &self.kind
    }
}

impl std::error::Error for Error {  }

impl fmt::Display for ErrorKind {
    #[inline]
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        match self {
            ErrorKind::Bind(e) => write!(f, "binding failed: {}", e),
            ErrorKind::Io(e) => write!(f, "I/O error: {}", e),
            ErrorKind::Collisions(_) => "collisions detected".fmt(f),
            ErrorKind::FailedFairings(_) => "launch fairing(s) failed".fmt(f),
            ErrorKind::InsecureSecretKey(_) => "insecure secret key config".fmt(f),
            ErrorKind::Config(_) => "failed to extract configuration".fmt(f),
            ErrorKind::SentinelAborts(_) => "sentinel(s) aborted".fmt(f),
            ErrorKind::Shutdown(_, Some(e)) => write!(f, "shutdown failed: {}", e),
            ErrorKind::Shutdown(_, None) => "shutdown failed".fmt(f),
        }
    }
}

impl fmt::Debug for Error {
    #[inline]
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        self.mark_handled();
        self.kind().fmt(f)
    }
}

impl fmt::Display for Error {
    #[inline]
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        self.mark_handled();
        write!(f, "{}", self.kind())
    }
}

impl Drop for Error {
    fn drop(&mut self) {
        // Don't panic if the message has been seen. Don't double-panic.
        if self.was_handled() || std::thread::panicking() {
            return
        }

        match self.kind() {
            ErrorKind::Bind(ref e) => {
                error!("Rocket failed to bind network socket to given address/port.");
                info_!("{}", e);
                panic!("aborting due to socket bind error");
            }
            ErrorKind::Io(ref e) => {
                error!("Rocket failed to launch due to an I/O error.");
                info_!("{}", e);
                panic!("aborting due to i/o error");
            }
            ErrorKind::Collisions(ref collisions) => {
                fn log_collisions<T: fmt::Display>(kind: &str, collisions: &[(T, T)]) {
                    if collisions.is_empty() { return }

                    error!("Rocket failed to launch due to the following {} collisions:", kind);
                    for &(ref a, ref b) in collisions {
                        info_!("{} {} {}", a, Paint::red("collides with").italic(), b)
                    }
                }

                log_collisions("route", &collisions.routes);
                log_collisions("catcher", &collisions.catchers);

                info_!("Note: Route collisions can usually be resolved by ranking routes.");
                panic!("routing collisions detected");
            }
            ErrorKind::FailedFairings(ref failures) => {
                error!("Rocket failed to launch due to failing fairings:");
                for fairing in failures {
                    info_!("{}", fairing.name);
                }

                panic!("aborting due to fairing failure(s)");
            }
            ErrorKind::InsecureSecretKey(profile) => {
                error!("secrets enabled in non-debug without `secret_key`");
                info_!("selected profile: {}", Paint::default(profile).bold());
                info_!("disable `secrets` feature or configure a `secret_key`");
                panic!("aborting due to insecure configuration")
            }
            ErrorKind::Config(error) => {
                crate::config::pretty_print_error(error.clone());
                panic!("aborting due to invalid configuration")
            }
            ErrorKind::SentinelAborts(ref failures) => {
                error!("Rocket failed to launch due to aborting sentinels:");
                for sentry in failures {
                    let name = Paint::default(sentry.type_name).bold();
                    let (file, line, col) = sentry.location;
                    info_!("{} ({}:{}:{})", name, file, line, col);
                }

                panic!("aborting due to sentinel-triggered abort(s)");
            }
            ErrorKind::Shutdown(_, error) => {
                error!("Rocket failed to shutdown gracefully.");
                if let Some(e) = error {
                    info_!("{}", e);
                }

                panic!("aborting due to failed shutdown");
            }
        }
    }
}