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
/*
 * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
 * SPDX-License-Identifier: Apache-2.0
 */

//! AWS-specific request ID support

use aws_smithy_runtime_api::client::result::SdkError;
use aws_smithy_runtime_api::http::Headers;
use aws_smithy_runtime_api::http::Response;
use aws_smithy_types::error::metadata::{Builder as ErrorMetadataBuilder, ErrorMetadata};

/// Constant for the [`ErrorMetadata`] extra field that contains the request ID
const AWS_REQUEST_ID: &str = "aws_request_id";

/// Implementers add a function to return an AWS request ID
pub trait RequestId {
    /// Returns the request ID, or `None` if the service could not be reached.
    fn request_id(&self) -> Option<&str>;
}

impl<E> RequestId for SdkError<E, Response> {
    fn request_id(&self) -> Option<&str> {
        match self {
            Self::ResponseError(err) => err.raw().headers().request_id(),
            Self::ServiceError(err) => err.raw().headers().request_id(),
            _ => None,
        }
    }
}

impl RequestId for ErrorMetadata {
    fn request_id(&self) -> Option<&str> {
        self.extra(AWS_REQUEST_ID)
    }
}

impl<B> RequestId for Response<B> {
    fn request_id(&self) -> Option<&str> {
        self.headers().request_id()
    }
}

impl RequestId for Headers {
    fn request_id(&self) -> Option<&str> {
        self.get("x-amzn-requestid")
            .or(self.get("x-amz-request-id"))
    }
}

impl<O, E> RequestId for Result<O, E>
where
    O: RequestId,
    E: RequestId,
{
    fn request_id(&self) -> Option<&str> {
        match self {
            Ok(ok) => ok.request_id(),
            Err(err) => err.request_id(),
        }
    }
}

/// Applies a request ID to a generic error builder
pub fn apply_request_id(builder: ErrorMetadataBuilder, headers: &Headers) -> ErrorMetadataBuilder {
    if let Some(request_id) = headers.request_id() {
        builder.custom(AWS_REQUEST_ID, request_id)
    } else {
        builder
    }
}

#[cfg(test)]
mod tests {
    use crate::request_id::{apply_request_id, RequestId, AWS_REQUEST_ID};
    use aws_smithy_runtime_api::client::orchestrator::HttpResponse;
    use aws_smithy_runtime_api::client::result::SdkError;
    use aws_smithy_runtime_api::http::Headers;
    use aws_smithy_types::body::SdkBody;
    use aws_smithy_types::error::ErrorMetadata;
    use http::{HeaderValue, Response};

    #[test]
    fn test_request_id_sdk_error() {
        let without_request_id =
            || HttpResponse::try_from(Response::builder().body(SdkBody::empty()).unwrap()).unwrap();
        let with_request_id = || {
            HttpResponse::try_from(
                Response::builder()
                    .header(
                        "x-amzn-requestid",
                        HeaderValue::from_static("some-request-id"),
                    )
                    .body(SdkBody::empty())
                    .unwrap(),
            )
            .unwrap()
        };
        assert_eq!(
            None,
            SdkError::<(), _>::response_error("test", without_request_id()).request_id()
        );
        assert_eq!(
            Some("some-request-id"),
            SdkError::<(), _>::response_error("test", with_request_id()).request_id()
        );
        assert_eq!(
            None,
            SdkError::service_error((), without_request_id()).request_id()
        );
        assert_eq!(
            Some("some-request-id"),
            SdkError::service_error((), with_request_id()).request_id()
        );
    }

    #[test]
    fn test_extract_request_id() {
        let mut headers = Headers::new();
        assert_eq!(None, headers.request_id());

        headers.append(
            "x-amzn-requestid",
            HeaderValue::from_static("some-request-id"),
        );
        assert_eq!(Some("some-request-id"), headers.request_id());

        headers.append(
            "x-amz-request-id",
            HeaderValue::from_static("other-request-id"),
        );
        assert_eq!(Some("some-request-id"), headers.request_id());

        headers.remove("x-amzn-requestid");
        assert_eq!(Some("other-request-id"), headers.request_id());
    }

    #[test]
    fn test_apply_request_id() {
        let mut headers = Headers::new();
        assert_eq!(
            ErrorMetadata::builder().build(),
            apply_request_id(ErrorMetadata::builder(), &headers).build(),
        );

        headers.append(
            "x-amzn-requestid",
            HeaderValue::from_static("some-request-id"),
        );
        assert_eq!(
            ErrorMetadata::builder()
                .custom(AWS_REQUEST_ID, "some-request-id")
                .build(),
            apply_request_id(ErrorMetadata::builder(), &headers).build(),
        );
    }

    #[test]
    fn test_error_metadata_request_id_impl() {
        let err = ErrorMetadata::builder()
            .custom(AWS_REQUEST_ID, "some-request-id")
            .build();
        assert_eq!(Some("some-request-id"), err.request_id());
    }
}