ruma_client_api/
error.rs

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
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
//! Errors that can be sent from the homeserver.

use std::{collections::BTreeMap, fmt, str::FromStr, sync::Arc};

use as_variant::as_variant;
use bytes::{BufMut, Bytes};
use ruma_common::{
    api::{
        error::{
            FromHttpResponseError, HeaderDeserializationError, HeaderSerializationError,
            IntoHttpError, MatrixErrorBody,
        },
        EndpointError, OutgoingResponse,
    },
    RoomVersionId,
};
use serde::{Deserialize, Serialize};
use serde_json::{from_slice as from_json_slice, Value as JsonValue};
use web_time::{Duration, SystemTime};

use crate::{
    http_headers::{http_date_to_system_time, system_time_to_http_date},
    PrivOwnedStr,
};

/// Deserialize and Serialize implementations for ErrorKind.
/// Separate module because it's a lot of code.
mod kind_serde;

/// An enum for the error kind.
///
/// Items may contain additional information.
#[derive(Clone, Debug, PartialEq, Eq)]
#[non_exhaustive]
pub enum ErrorKind {
    /// M_FORBIDDEN
    #[non_exhaustive]
    Forbidden {
        /// The `WWW-Authenticate` header error message.
        #[cfg(feature = "unstable-msc2967")]
        authenticate: Option<AuthenticateError>,
    },

    /// M_UNKNOWN_TOKEN
    UnknownToken {
        /// If this is `true`, the client can acquire a new access token by specifying the device
        /// ID it is already using to the login API.
        ///
        /// For more information, see [the spec].
        ///
        /// [the spec]: https://spec.matrix.org/latest/client-server-api/#soft-logout
        soft_logout: bool,
    },

    /// M_MISSING_TOKEN
    MissingToken,

    /// M_BAD_JSON
    BadJson,

    /// M_NOT_JSON
    NotJson,

    /// M_NOT_FOUND
    NotFound,

    /// M_LIMIT_EXCEEDED
    LimitExceeded {
        /// How long a client should wait before they can try again.
        retry_after: Option<RetryAfter>,
    },

    /// M_UNKNOWN
    Unknown,

    /// M_UNRECOGNIZED
    Unrecognized,

    /// M_UNAUTHORIZED
    Unauthorized,

    /// M_USER_DEACTIVATED
    UserDeactivated,

    /// M_USER_IN_USE
    UserInUse,

    /// M_INVALID_USERNAME
    InvalidUsername,

    /// M_ROOM_IN_USE
    RoomInUse,

    /// M_INVALID_ROOM_STATE
    InvalidRoomState,

    /// M_THREEPID_IN_USE
    ThreepidInUse,

    /// M_THREEPID_NOT_FOUND
    ThreepidNotFound,

    /// M_THREEPID_AUTH_FAILED
    ThreepidAuthFailed,

    /// M_THREEPID_DENIED
    ThreepidDenied,

    /// M_SERVER_NOT_TRUSTED
    ServerNotTrusted,

    /// M_UNSUPPORTED_ROOM_VERSION
    UnsupportedRoomVersion,

    /// M_INCOMPATIBLE_ROOM_VERSION
    IncompatibleRoomVersion {
        /// The room's version.
        room_version: RoomVersionId,
    },

    /// M_BAD_STATE
    BadState,

    /// M_GUEST_ACCESS_FORBIDDEN
    GuestAccessForbidden,

    /// M_CAPTCHA_NEEDED
    CaptchaNeeded,

    /// M_CAPTCHA_INVALID
    CaptchaInvalid,

    /// M_MISSING_PARAM
    MissingParam,

    /// M_INVALID_PARAM
    InvalidParam,

    /// M_TOO_LARGE
    TooLarge,

    /// M_EXCLUSIVE
    Exclusive,

    /// M_RESOURCE_LIMIT_EXCEEDED
    ResourceLimitExceeded {
        /// A URI giving a contact method for the server administrator.
        admin_contact: String,
    },

    /// M_CANNOT_LEAVE_SERVER_NOTICE_ROOM
    CannotLeaveServerNoticeRoom,

    /// M_WEAK_PASSWORD
    WeakPassword,

    /// M_UNABLE_TO_AUTHORISE_JOIN
    UnableToAuthorizeJoin,

    /// M_UNABLE_TO_GRANT_JOIN
    UnableToGrantJoin,

    /// M_BAD_ALIAS
    BadAlias,

    /// M_DUPLICATE_ANNOTATION
    DuplicateAnnotation,

    /// M_NOT_YET_UPLOADED
    NotYetUploaded,

    /// M_CANNOT_OVERWRITE_MEDIA
    CannotOverwriteMedia,

    /// M_UNKNOWN_POS for sliding sync
    #[cfg(any(feature = "unstable-msc3575", feature = "unstable-msc4186"))]
    UnknownPos,

    /// M_URL_NOT_SET
    UrlNotSet,

    /// M_BAD_STATUS
    BadStatus {
        /// The HTTP status code of the response.
        status: Option<http::StatusCode>,

        /// The body of the response.
        body: Option<String>,
    },

    /// M_CONNECTION_FAILED
    ConnectionFailed,

    /// M_CONNECTION_TIMEOUT
    ConnectionTimeout,

    /// M_WRONG_ROOM_KEYS_VERSION
    WrongRoomKeysVersion {
        /// The currently active backup version.
        current_version: Option<String>,
    },

    /// M_UNACTIONABLE
    #[cfg(feature = "unstable-msc3843")]
    Unactionable,

    /// M_USER_LOCKED
    UserLocked,

    #[doc(hidden)]
    _Custom { errcode: PrivOwnedStr, extra: Extra },
}

impl ErrorKind {
    /// Constructs an empty [`ErrorKind::Forbidden`] variant.
    pub fn forbidden() -> Self {
        Self::Forbidden {
            #[cfg(feature = "unstable-msc2967")]
            authenticate: None,
        }
    }

    /// Constructs an [`ErrorKind::Forbidden`] variant with the given `WWW-Authenticate` header
    /// error message.
    #[cfg(feature = "unstable-msc2967")]
    pub fn forbidden_with_authenticate(authenticate: AuthenticateError) -> Self {
        Self::Forbidden { authenticate: Some(authenticate) }
    }
}

#[doc(hidden)]
#[derive(Clone, Debug, PartialEq, Eq)]
pub struct Extra(BTreeMap<String, JsonValue>);

impl AsRef<str> for ErrorKind {
    fn as_ref(&self) -> &str {
        match self {
            Self::Forbidden { .. } => "M_FORBIDDEN",
            Self::UnknownToken { .. } => "M_UNKNOWN_TOKEN",
            Self::MissingToken => "M_MISSING_TOKEN",
            Self::BadJson => "M_BAD_JSON",
            Self::NotJson => "M_NOT_JSON",
            Self::NotFound => "M_NOT_FOUND",
            Self::LimitExceeded { .. } => "M_LIMIT_EXCEEDED",
            Self::Unknown => "M_UNKNOWN",
            Self::Unrecognized => "M_UNRECOGNIZED",
            Self::Unauthorized => "M_UNAUTHORIZED",
            Self::UserDeactivated => "M_USER_DEACTIVATED",
            Self::UserInUse => "M_USER_IN_USE",
            Self::InvalidUsername => "M_INVALID_USERNAME",
            Self::RoomInUse => "M_ROOM_IN_USE",
            Self::InvalidRoomState => "M_INVALID_ROOM_STATE",
            Self::ThreepidInUse => "M_THREEPID_IN_USE",
            Self::ThreepidNotFound => "M_THREEPID_NOT_FOUND",
            Self::ThreepidAuthFailed => "M_THREEPID_AUTH_FAILED",
            Self::ThreepidDenied => "M_THREEPID_DENIED",
            Self::ServerNotTrusted => "M_SERVER_NOT_TRUSTED",
            Self::UnsupportedRoomVersion => "M_UNSUPPORTED_ROOM_VERSION",
            Self::IncompatibleRoomVersion { .. } => "M_INCOMPATIBLE_ROOM_VERSION",
            Self::BadState => "M_BAD_STATE",
            Self::GuestAccessForbidden => "M_GUEST_ACCESS_FORBIDDEN",
            Self::CaptchaNeeded => "M_CAPTCHA_NEEDED",
            Self::CaptchaInvalid => "M_CAPTCHA_INVALID",
            Self::MissingParam => "M_MISSING_PARAM",
            Self::InvalidParam => "M_INVALID_PARAM",
            Self::TooLarge => "M_TOO_LARGE",
            Self::Exclusive => "M_EXCLUSIVE",
            Self::ResourceLimitExceeded { .. } => "M_RESOURCE_LIMIT_EXCEEDED",
            Self::CannotLeaveServerNoticeRoom => "M_CANNOT_LEAVE_SERVER_NOTICE_ROOM",
            Self::WeakPassword => "M_WEAK_PASSWORD",
            Self::UnableToAuthorizeJoin => "M_UNABLE_TO_AUTHORISE_JOIN",
            Self::UnableToGrantJoin => "M_UNABLE_TO_GRANT_JOIN",
            Self::BadAlias => "M_BAD_ALIAS",
            Self::DuplicateAnnotation => "M_DUPLICATE_ANNOTATION",
            Self::NotYetUploaded => "M_NOT_YET_UPLOADED",
            Self::CannotOverwriteMedia => "M_CANNOT_OVERWRITE_MEDIA",
            #[cfg(any(feature = "unstable-msc3575", feature = "unstable-msc4186"))]
            Self::UnknownPos => "M_UNKNOWN_POS",
            Self::UrlNotSet => "M_URL_NOT_SET",
            Self::BadStatus { .. } => "M_BAD_STATUS",
            Self::ConnectionFailed => "M_CONNECTION_FAILED",
            Self::ConnectionTimeout => "M_CONNECTION_TIMEOUT",
            Self::WrongRoomKeysVersion { .. } => "M_WRONG_ROOM_KEYS_VERSION",
            #[cfg(feature = "unstable-msc3843")]
            Self::Unactionable => "M_UNACTIONABLE",
            Self::UserLocked => "M_USER_LOCKED",
            Self::_Custom { errcode, .. } => &errcode.0,
        }
    }
}

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

/// The body of a Matrix Client API error.
#[derive(Debug, Clone)]
#[allow(clippy::exhaustive_enums)]
pub enum ErrorBody {
    /// A JSON body with the fields expected for Client API errors.
    Standard {
        /// A value which can be used to handle an error message.
        kind: ErrorKind,

        /// A human-readable error message, usually a sentence explaining what went wrong.
        message: String,
    },

    /// A JSON body with an unexpected structure.
    Json(JsonValue),

    /// A response body that is not valid JSON.
    NotJson {
        /// The raw bytes of the response body.
        bytes: Bytes,

        /// The error from trying to deserialize the bytes as JSON.
        deserialization_error: Arc<serde_json::Error>,
    },
}

/// A JSON body with the fields expected for Client API errors.
#[derive(Clone, Debug, Deserialize, Serialize)]
#[allow(clippy::exhaustive_structs)]
pub struct StandardErrorBody {
    /// A value which can be used to handle an error message.
    #[serde(flatten)]
    pub kind: ErrorKind,

    /// A human-readable error message, usually a sentence explaining what went wrong.
    #[serde(rename = "error")]
    pub message: String,
}

/// A Matrix Error
#[derive(Debug, Clone)]
#[cfg_attr(not(feature = "unstable-exhaustive-types"), non_exhaustive)]
pub struct Error {
    /// The http status code.
    pub status_code: http::StatusCode,

    /// The http response's body.
    pub body: ErrorBody,
}

impl Error {
    /// Constructs a new `Error` with the given status code and body.
    ///
    /// This is equivalent to calling `body.into_error(status_code)`.
    pub fn new(status_code: http::StatusCode, body: ErrorBody) -> Self {
        Self { status_code, body }
    }

    /// If `self` is a server error in the `errcode` + `error` format expected
    /// for client-server API endpoints, returns the error kind (`errcode`).
    pub fn error_kind(&self) -> Option<&ErrorKind> {
        as_variant!(&self.body, ErrorBody::Standard { kind, .. } => kind)
    }
}

impl EndpointError for Error {
    fn from_http_response<T: AsRef<[u8]>>(response: http::Response<T>) -> Self {
        let status = response.status();

        let body_bytes = &response.body().as_ref();
        let error_body: ErrorBody = match from_json_slice(body_bytes) {
            Ok(StandardErrorBody { mut kind, message }) => {
                let headers = response.headers();

                match &mut kind {
                    #[cfg(feature = "unstable-msc2967")]
                    ErrorKind::Forbidden { authenticate } => {
                        *authenticate = headers
                            .get(http::header::WWW_AUTHENTICATE)
                            .and_then(|val| val.to_str().ok())
                            .and_then(AuthenticateError::from_str);
                    }
                    ErrorKind::LimitExceeded { retry_after } => {
                        // The Retry-After header takes precedence over the retry_after_ms field in
                        // the body.
                        if let Some(Ok(retry_after_header)) =
                            headers.get(http::header::RETRY_AFTER).map(RetryAfter::try_from)
                        {
                            *retry_after = Some(retry_after_header);
                        }
                    }
                    _ => {}
                }

                ErrorBody::Standard { kind, message }
            }
            Err(_) => match MatrixErrorBody::from_bytes(body_bytes) {
                MatrixErrorBody::Json(json) => ErrorBody::Json(json),
                MatrixErrorBody::NotJson { bytes, deserialization_error, .. } => {
                    ErrorBody::NotJson { bytes, deserialization_error }
                }
            },
        };

        error_body.into_error(status)
    }
}

impl fmt::Display for Error {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        let status_code = self.status_code.as_u16();
        match &self.body {
            ErrorBody::Standard { kind, message } => {
                write!(f, "[{status_code} / {kind}] {message}")
            }
            ErrorBody::Json(json) => write!(f, "[{status_code}] {json}"),
            ErrorBody::NotJson { .. } => write!(f, "[{status_code}] <non-json bytes>"),
        }
    }
}

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

impl ErrorBody {
    /// Convert the ErrorBody into an Error by adding the http status code.
    ///
    /// This is equivalent to calling `Error::new(status_code, self)`.
    pub fn into_error(self, status_code: http::StatusCode) -> Error {
        Error { status_code, body: self }
    }
}

impl OutgoingResponse for Error {
    fn try_into_http_response<T: Default + BufMut>(
        self,
    ) -> Result<http::Response<T>, IntoHttpError> {
        let mut builder = http::Response::builder()
            .header(http::header::CONTENT_TYPE, "application/json")
            .status(self.status_code);

        #[allow(clippy::collapsible_match)]
        if let ErrorBody::Standard { kind, .. } = &self.body {
            match kind {
                #[cfg(feature = "unstable-msc2967")]
                ErrorKind::Forbidden { authenticate: Some(auth_error) } => {
                    builder = builder.header(http::header::WWW_AUTHENTICATE, auth_error);
                }
                ErrorKind::LimitExceeded { retry_after: Some(retry_after) } => {
                    let header_value = http::HeaderValue::try_from(retry_after)?;
                    builder = builder.header(http::header::RETRY_AFTER, header_value);
                }
                _ => {}
            }
        }

        builder
            .body(match self.body {
                ErrorBody::Standard { kind, message } => {
                    ruma_common::serde::json_to_buf(&StandardErrorBody { kind, message })?
                }
                ErrorBody::Json(json) => ruma_common::serde::json_to_buf(&json)?,
                ErrorBody::NotJson { .. } => {
                    return Err(IntoHttpError::Json(serde::ser::Error::custom(
                        "attempted to serialize ErrorBody::NotJson",
                    )));
                }
            })
            .map_err(Into::into)
    }
}

/// Errors in the `WWW-Authenticate` header.
///
/// To construct this use `::from_str()`. To get its serialized form, use its
/// `TryInto<http::HeaderValue>` implementation.
#[cfg(feature = "unstable-msc2967")]
#[derive(Clone, Debug, PartialEq, Eq)]
#[non_exhaustive]
pub enum AuthenticateError {
    /// insufficient_scope
    ///
    /// Encountered when authentication is handled by OpenID Connect and the current access token
    /// isn't authorized for the proper scope for this request. It should be paired with a
    /// `401` status code and a `M_FORBIDDEN` error.
    InsufficientScope {
        /// The new scope to request an authorization for.
        scope: String,
    },

    #[doc(hidden)]
    _Custom { errcode: PrivOwnedStr, attributes: AuthenticateAttrs },
}

#[cfg(feature = "unstable-msc2967")]
#[doc(hidden)]
#[derive(Clone, Debug, PartialEq, Eq)]
pub struct AuthenticateAttrs(BTreeMap<String, String>);

#[cfg(feature = "unstable-msc2967")]
impl AuthenticateError {
    /// Construct an `AuthenticateError` from a string.
    ///
    /// Returns `None` if the string doesn't contain an error.
    fn from_str(s: &str) -> Option<Self> {
        if let Some(val) = s.strip_prefix("Bearer").map(str::trim) {
            let mut errcode = None;
            let mut attrs = BTreeMap::new();

            // Split the attributes separated by commas and optionally spaces, then split the keys
            // and the values, with the values optionally surrounded by double quotes.
            for (key, value) in val
                .split(',')
                .filter_map(|attr| attr.trim().split_once('='))
                .map(|(key, value)| (key, value.trim_matches('"')))
            {
                if key == "error" {
                    errcode = Some(value);
                } else {
                    attrs.insert(key.to_owned(), value.to_owned());
                }
            }

            if let Some(errcode) = errcode {
                let error = if let Some(scope) =
                    attrs.get("scope").filter(|_| errcode == "insufficient_scope")
                {
                    AuthenticateError::InsufficientScope { scope: scope.to_owned() }
                } else {
                    AuthenticateError::_Custom {
                        errcode: PrivOwnedStr(errcode.into()),
                        attributes: AuthenticateAttrs(attrs),
                    }
                };

                return Some(error);
            }
        }

        None
    }
}

#[cfg(feature = "unstable-msc2967")]
impl TryFrom<&AuthenticateError> for http::HeaderValue {
    type Error = http::header::InvalidHeaderValue;

    fn try_from(error: &AuthenticateError) -> Result<Self, Self::Error> {
        let s = match error {
            AuthenticateError::InsufficientScope { scope } => {
                format!("Bearer error=\"insufficient_scope\", scope=\"{scope}\"")
            }
            AuthenticateError::_Custom { errcode, attributes } => {
                let mut s = format!("Bearer error=\"{}\"", errcode.0);

                for (key, value) in attributes.0.iter() {
                    s.push_str(&format!(", {key}=\"{value}\""));
                }

                s
            }
        };

        s.try_into()
    }
}

/// How long a client should wait before it tries again.
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
#[allow(clippy::exhaustive_enums)]
pub enum RetryAfter {
    /// The client should wait for the given duration.
    ///
    /// This variant should be preferred for backwards compatibility, as it will also populate the
    /// `retry_after_ms` field in the body of the response.
    Delay(Duration),
    /// The client should wait for the given date and time.
    DateTime(SystemTime),
}

impl TryFrom<&http::HeaderValue> for RetryAfter {
    type Error = HeaderDeserializationError;

    fn try_from(value: &http::HeaderValue) -> Result<Self, Self::Error> {
        if value.as_bytes().iter().all(|b| b.is_ascii_digit()) {
            // It should be a duration.
            Ok(Self::Delay(Duration::from_secs(u64::from_str(value.to_str()?)?)))
        } else {
            // It should be a date.
            Ok(Self::DateTime(http_date_to_system_time(value)?))
        }
    }
}

impl TryFrom<&RetryAfter> for http::HeaderValue {
    type Error = HeaderSerializationError;

    fn try_from(value: &RetryAfter) -> Result<Self, Self::Error> {
        match value {
            RetryAfter::Delay(duration) => Ok(duration.as_secs().into()),
            RetryAfter::DateTime(time) => system_time_to_http_date(time),
        }
    }
}

/// Extension trait for `FromHttpResponseError<ruma_client_api::Error>`.
pub trait FromHttpResponseErrorExt {
    /// If `self` is a server error in the `errcode` + `error` format expected
    /// for client-server API endpoints, returns the error kind (`errcode`).
    fn error_kind(&self) -> Option<&ErrorKind>;
}

impl FromHttpResponseErrorExt for FromHttpResponseError<Error> {
    fn error_kind(&self) -> Option<&ErrorKind> {
        as_variant!(self, Self::Server)?.error_kind()
    }
}

#[cfg(test)]
mod tests {
    use assert_matches2::assert_matches;
    use ruma_common::api::{EndpointError, OutgoingResponse};
    use serde_json::{
        from_slice as from_json_slice, from_value as from_json_value, json, Value as JsonValue,
    };
    use web_time::{Duration, UNIX_EPOCH};

    use super::{Error, ErrorBody, ErrorKind, RetryAfter, StandardErrorBody};

    #[test]
    fn deserialize_forbidden() {
        let deserialized: StandardErrorBody = from_json_value(json!({
            "errcode": "M_FORBIDDEN",
            "error": "You are not authorized to ban users in this room.",
        }))
        .unwrap();

        assert_eq!(
            deserialized.kind,
            ErrorKind::Forbidden {
                #[cfg(feature = "unstable-msc2967")]
                authenticate: None
            }
        );
        assert_eq!(deserialized.message, "You are not authorized to ban users in this room.");
    }

    #[test]
    fn deserialize_wrong_room_key_version() {
        let deserialized: StandardErrorBody = from_json_value(json!({
            "current_version": "42",
            "errcode": "M_WRONG_ROOM_KEYS_VERSION",
            "error": "Wrong backup version."
        }))
        .expect("We should be able to deserialize a wrong room keys version error");

        assert_matches!(deserialized.kind, ErrorKind::WrongRoomKeysVersion { current_version });
        assert_eq!(current_version.as_deref(), Some("42"));
        assert_eq!(deserialized.message, "Wrong backup version.");
    }

    #[cfg(feature = "unstable-msc2967")]
    #[test]
    fn custom_authenticate_error_sanity() {
        use super::AuthenticateError;

        let s = "Bearer error=\"custom_error\", misc=\"some content\"";

        let error = AuthenticateError::from_str(s).unwrap();
        let error_header = http::HeaderValue::try_from(&error).unwrap();

        assert_eq!(error_header.to_str().unwrap(), s);
    }

    #[cfg(feature = "unstable-msc2967")]
    #[test]
    fn serialize_insufficient_scope() {
        use super::AuthenticateError;

        let error =
            AuthenticateError::InsufficientScope { scope: "something_privileged".to_owned() };
        let error_header = http::HeaderValue::try_from(&error).unwrap();

        assert_eq!(
            error_header.to_str().unwrap(),
            "Bearer error=\"insufficient_scope\", scope=\"something_privileged\""
        );
    }

    #[cfg(feature = "unstable-msc2967")]
    #[test]
    fn deserialize_insufficient_scope() {
        use super::AuthenticateError;

        let response = http::Response::builder()
            .header(
                http::header::WWW_AUTHENTICATE,
                "Bearer error=\"insufficient_scope\", scope=\"something_privileged\"",
            )
            .status(http::StatusCode::UNAUTHORIZED)
            .body(
                serde_json::to_string(&json!({
                    "errcode": "M_FORBIDDEN",
                    "error": "Insufficient privilege",
                }))
                .unwrap(),
            )
            .unwrap();
        let error = Error::from_http_response(response);

        assert_eq!(error.status_code, http::StatusCode::UNAUTHORIZED);
        assert_matches!(error.body, ErrorBody::Standard { kind, message });
        assert_matches!(kind, ErrorKind::Forbidden { authenticate });
        assert_eq!(message, "Insufficient privilege");
        assert_matches!(authenticate, Some(AuthenticateError::InsufficientScope { scope }));
        assert_eq!(scope, "something_privileged");
    }

    #[test]
    fn deserialize_limit_exceeded_no_retry_after() {
        let response = http::Response::builder()
            .status(http::StatusCode::TOO_MANY_REQUESTS)
            .body(
                serde_json::to_string(&json!({
                    "errcode": "M_LIMIT_EXCEEDED",
                    "error": "Too many requests",
                }))
                .unwrap(),
            )
            .unwrap();
        let error = Error::from_http_response(response);

        assert_eq!(error.status_code, http::StatusCode::TOO_MANY_REQUESTS);
        assert_matches!(
            error.body,
            ErrorBody::Standard { kind: ErrorKind::LimitExceeded { retry_after: None }, message }
        );
        assert_eq!(message, "Too many requests");
    }

    #[test]
    fn deserialize_limit_exceeded_retry_after_body() {
        let response = http::Response::builder()
            .status(http::StatusCode::TOO_MANY_REQUESTS)
            .body(
                serde_json::to_string(&json!({
                    "errcode": "M_LIMIT_EXCEEDED",
                    "error": "Too many requests",
                    "retry_after_ms": 2000,
                }))
                .unwrap(),
            )
            .unwrap();
        let error = Error::from_http_response(response);

        assert_eq!(error.status_code, http::StatusCode::TOO_MANY_REQUESTS);
        assert_matches!(
            error.body,
            ErrorBody::Standard {
                kind: ErrorKind::LimitExceeded { retry_after: Some(retry_after) },
                message
            }
        );
        assert_matches!(retry_after, RetryAfter::Delay(delay));
        assert_eq!(delay.as_millis(), 2000);
        assert_eq!(message, "Too many requests");
    }

    #[test]
    fn deserialize_limit_exceeded_retry_after_header_delay() {
        let response = http::Response::builder()
            .status(http::StatusCode::TOO_MANY_REQUESTS)
            .header(http::header::RETRY_AFTER, "2")
            .body(
                serde_json::to_string(&json!({
                    "errcode": "M_LIMIT_EXCEEDED",
                    "error": "Too many requests",
                }))
                .unwrap(),
            )
            .unwrap();
        let error = Error::from_http_response(response);

        assert_eq!(error.status_code, http::StatusCode::TOO_MANY_REQUESTS);
        assert_matches!(
            error.body,
            ErrorBody::Standard {
                kind: ErrorKind::LimitExceeded { retry_after: Some(retry_after) },
                message
            }
        );
        assert_matches!(retry_after, RetryAfter::Delay(delay));
        assert_eq!(delay.as_millis(), 2000);
        assert_eq!(message, "Too many requests");
    }

    #[test]
    fn deserialize_limit_exceeded_retry_after_header_datetime() {
        let response = http::Response::builder()
            .status(http::StatusCode::TOO_MANY_REQUESTS)
            .header(http::header::RETRY_AFTER, "Fri, 15 May 2015 15:34:21 GMT")
            .body(
                serde_json::to_string(&json!({
                    "errcode": "M_LIMIT_EXCEEDED",
                    "error": "Too many requests",
                }))
                .unwrap(),
            )
            .unwrap();
        let error = Error::from_http_response(response);

        assert_eq!(error.status_code, http::StatusCode::TOO_MANY_REQUESTS);
        assert_matches!(
            error.body,
            ErrorBody::Standard {
                kind: ErrorKind::LimitExceeded { retry_after: Some(retry_after) },
                message
            }
        );
        assert_matches!(retry_after, RetryAfter::DateTime(time));
        assert_eq!(time.duration_since(UNIX_EPOCH).unwrap().as_secs(), 1_431_704_061);
        assert_eq!(message, "Too many requests");
    }

    #[test]
    fn deserialize_limit_exceeded_retry_after_header_over_body() {
        let response = http::Response::builder()
            .status(http::StatusCode::TOO_MANY_REQUESTS)
            .header(http::header::RETRY_AFTER, "2")
            .body(
                serde_json::to_string(&json!({
                    "errcode": "M_LIMIT_EXCEEDED",
                    "error": "Too many requests",
                    "retry_after_ms": 3000,
                }))
                .unwrap(),
            )
            .unwrap();
        let error = Error::from_http_response(response);

        assert_eq!(error.status_code, http::StatusCode::TOO_MANY_REQUESTS);
        assert_matches!(
            error.body,
            ErrorBody::Standard {
                kind: ErrorKind::LimitExceeded { retry_after: Some(retry_after) },
                message
            }
        );
        assert_matches!(retry_after, RetryAfter::Delay(delay));
        assert_eq!(delay.as_millis(), 2000);
        assert_eq!(message, "Too many requests");
    }

    #[test]
    fn serialize_limit_exceeded_retry_after_none() {
        let error = Error::new(
            http::StatusCode::TOO_MANY_REQUESTS,
            ErrorBody::Standard {
                kind: ErrorKind::LimitExceeded { retry_after: None },
                message: "Too many requests".to_owned(),
            },
        );

        let response = error.try_into_http_response::<Vec<u8>>().unwrap();

        assert_eq!(response.status(), http::StatusCode::TOO_MANY_REQUESTS);
        assert_eq!(response.headers().get(http::header::RETRY_AFTER), None);

        let json_body: JsonValue = from_json_slice(response.body()).unwrap();
        assert_eq!(
            json_body,
            json!({
                "errcode": "M_LIMIT_EXCEEDED",
                "error": "Too many requests",
            })
        );
    }

    #[test]
    fn serialize_limit_exceeded_retry_after_delay() {
        let error = Error::new(
            http::StatusCode::TOO_MANY_REQUESTS,
            ErrorBody::Standard {
                kind: ErrorKind::LimitExceeded {
                    retry_after: Some(RetryAfter::Delay(Duration::from_secs(3))),
                },
                message: "Too many requests".to_owned(),
            },
        );

        let response = error.try_into_http_response::<Vec<u8>>().unwrap();

        assert_eq!(response.status(), http::StatusCode::TOO_MANY_REQUESTS);
        let retry_after_header = response.headers().get(http::header::RETRY_AFTER).unwrap();
        assert_eq!(retry_after_header.to_str().unwrap(), "3");

        let json_body: JsonValue = from_json_slice(response.body()).unwrap();
        assert_eq!(
            json_body,
            json!({
                "errcode": "M_LIMIT_EXCEEDED",
                "error": "Too many requests",
                "retry_after_ms": 3000,
            })
        );
    }

    #[test]
    fn serialize_limit_exceeded_retry_after_datetime() {
        let error = Error::new(
            http::StatusCode::TOO_MANY_REQUESTS,
            ErrorBody::Standard {
                kind: ErrorKind::LimitExceeded {
                    retry_after: Some(RetryAfter::DateTime(
                        UNIX_EPOCH + Duration::from_secs(1_431_704_061),
                    )),
                },
                message: "Too many requests".to_owned(),
            },
        );

        let response = error.try_into_http_response::<Vec<u8>>().unwrap();

        assert_eq!(response.status(), http::StatusCode::TOO_MANY_REQUESTS);
        let retry_after_header = response.headers().get(http::header::RETRY_AFTER).unwrap();
        assert_eq!(retry_after_header.to_str().unwrap(), "Fri, 15 May 2015 15:34:21 GMT");

        let json_body: JsonValue = from_json_slice(response.body()).unwrap();
        assert_eq!(
            json_body,
            json!({
                "errcode": "M_LIMIT_EXCEEDED",
                "error": "Too many requests",
            })
        );
    }

    #[test]
    fn serialize_user_locked() {
        let error = Error::new(
            http::StatusCode::UNAUTHORIZED,
            ErrorBody::Standard {
                kind: ErrorKind::UserLocked,
                message: "This account has been locked".to_owned(),
            },
        );

        let response = error.try_into_http_response::<Vec<u8>>().unwrap();

        assert_eq!(response.status(), http::StatusCode::UNAUTHORIZED);
        let json_body: JsonValue = from_json_slice(response.body()).unwrap();
        assert_eq!(
            json_body,
            json!({
                "errcode": "M_USER_LOCKED",
                "error": "This account has been locked",
                "soft_logout": true,
            })
        );
    }
}