cloud_sdk_reqwest/asynchronous/
client.rs

1use core::fmt;
2use std::sync::Arc;
3
4use cloud_sdk::Method;
5use cloud_sdk::transport::{
6    AsyncTransport, BoundTransport, EndpointIdentity, EndpointIdentityError, ResponseMetadata,
7    ResponseStorageSanitizer, ResponseWriter, StatusCode, TransportRequest,
8};
9use cloud_sdk_sanitization::{SecretBuffer, sanitize_bytes};
10use reqwest::header::{AUTHORIZATION, HeaderName, HeaderValue};
11use reqwest::{Body, Client};
12
13use crate::shared::{
14    BearerToken, CredentialStateError, CredentialStore, HttpsEndpoint, TokenRotationError,
15    TransportError, capture_response_headers, parse_rate_limit, parse_response_content_type,
16};
17
18use super::body::SanitizedBuffer;
19
20/// Hardened provider-neutral reqwest asynchronous transport.
21///
22/// The adapter uses reqwest's Tokio-based execution internally but does not
23/// install or own a runtime. Callers must poll it from a compatible executor.
24#[derive(Clone)]
25pub struct AsyncClient {
26    client: Client,
27    endpoint: HttpsEndpoint,
28    credentials: Arc<CredentialStore>,
29}
30
31impl AsyncClient {
32    pub(super) fn new(client: Client, endpoint: HttpsEndpoint, token: BearerToken) -> Self {
33        Self {
34            client,
35            endpoint,
36            credentials: Arc::new(CredentialStore::new(token)),
37        }
38    }
39
40    /// Atomically replaces the bearer token used by newly started requests.
41    ///
42    /// In-flight requests retain their previous snapshot. No credential lock
43    /// is held across network I/O or `.await`.
44    pub fn rotate_bearer_token(
45        &self,
46        replacement: BearerToken,
47    ) -> Result<(), CredentialStateError> {
48        self.credentials.rotate(replacement)
49    }
50
51    /// Validates and rotates from mutable bytes, clearing the complete source
52    /// on success or failure. Rejected input leaves the active token unchanged.
53    pub fn rotate_bearer_token_from_mut_bytes(
54        &self,
55        source: &mut [u8],
56    ) -> Result<(), TokenRotationError> {
57        self.credentials.rotate_from_mut_bytes(source)
58    }
59
60    /// Validates and rotates from guarded storage. Dropping the consumed guard
61    /// clears the complete source on success or failure.
62    pub fn rotate_bearer_token_from_secret_buffer(
63        &self,
64        source: SecretBuffer<'_>,
65    ) -> Result<(), TokenRotationError> {
66        self.credentials.rotate_from_secret_buffer(source)
67    }
68
69    async fn send_inner(
70        &self,
71        request: TransportRequest<'_>,
72        response_writer: &mut ResponseWriter<'_>,
73    ) -> Result<(), TransportError> {
74        if response_writer.is_committed() {
75            return Err(TransportError::ResponseCommitFailed);
76        }
77        let url = self
78            .endpoint
79            .compose(request.target())
80            .map_err(|_| TransportError::TargetRejected)?;
81        let token_snapshot = self
82            .credentials
83            .snapshot()
84            .map_err(|_| TransportError::CredentialStateUnavailable)?;
85        let authorization = token_snapshot
86            .header_value()
87            .map_err(|_| TransportError::HeaderRejected)?;
88        let mut outbound = self
89            .client
90            .request(map_method(request.method())?, url)
91            .header(AUTHORIZATION, authorization);
92
93        for header in request.headers().as_slice() {
94            let name = HeaderName::from_bytes(header.name().as_str().as_bytes())
95                .map_err(|_| TransportError::HeaderRejected)?;
96            let mut value = HeaderValue::from_str(header.value().as_str())
97                .map_err(|_| TransportError::HeaderRejected)?;
98            value.set_sensitive(matches!(
99                header.sensitivity(),
100                cloud_sdk::transport::HeaderSensitivity::Sensitive
101            ));
102            outbound = outbound.header(name, value);
103        }
104        if !request.body().is_empty() && request.headers().get("content-type").is_none() {
105            return Err(TransportError::MissingContentType);
106        }
107
108        if !request.body().is_empty() {
109            let body = SanitizedBuffer::copy_from(request.body())
110                .map_err(|_| TransportError::RequestBodyAllocationFailed)?;
111            let _ = u64::try_from(request.body().len())
112                .map_err(|_| TransportError::RequestBodyTooLarge)?;
113            outbound = outbound.body(Body::from(body.into_bytes()));
114        }
115
116        let mut response = outbound.send().await.map_err(classify_reqwest_error)?;
117        self.endpoint
118            .verify_origin(response.url())
119            .map_err(|_| TransportError::ResponseOriginChanged)?;
120        if response.content_length().is_some_and(|length| {
121            u64::try_from(response_writer.body_capacity()).map_or(true, |cap| length > cap)
122        }) {
123            return Err(TransportError::ResponseTooLarge);
124        }
125        let status =
126            StatusCode::new(response.status().as_u16()).ok_or(TransportError::InvalidStatus)?;
127        let buffered = read_response(&mut response, response_writer.body_capacity()).await?;
128        let headers = capture_response_headers(response.headers())?;
129        let rate_limit = parse_rate_limit(&headers)?;
130        let content_type = parse_response_content_type(&headers)?;
131        let body_len = buffered.len();
132        let initialized = response_writer
133            .body_mut()
134            .map_err(|_| TransportError::ResponseCommitFailed)?
135            .get_mut(..body_len)
136            .ok_or(TransportError::ResponseReadFailed)?;
137        initialized.copy_from_slice(buffered.as_ref());
138        let metadata = ResponseMetadata::EMPTY.with_headers(headers);
139        let metadata = content_type.map_or(metadata, |value| metadata.with_content_type(value));
140        let metadata = rate_limit.map_or(metadata, |value| metadata.with_rate_limit(value));
141        drop(token_snapshot);
142        response_writer
143            .commit(status, body_len, metadata)
144            .map_err(|_| TransportError::ResponseCommitFailed)
145    }
146}
147
148impl AsyncTransport for AsyncClient {
149    type Error = TransportError;
150
151    async fn send<'transport, 'request, 'writer>(
152        &'transport self,
153        request: TransportRequest<'request>,
154        response: &'writer mut ResponseWriter<'_>,
155    ) -> Result<(), Self::Error>
156    where
157        'transport: 'writer,
158        'request: 'writer,
159    {
160        self.send_inner(request, response).await
161    }
162}
163
164impl ResponseStorageSanitizer for AsyncClient {
165    fn sanitize_response_storage(&self, response_storage: &mut [u8]) {
166        sanitize_bytes(response_storage);
167    }
168}
169
170impl BoundTransport for AsyncClient {
171    fn endpoint_identity(&self) -> Result<EndpointIdentity<'_>, EndpointIdentityError> {
172        self.endpoint.identity()
173    }
174}
175
176impl fmt::Debug for AsyncClient {
177    fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result {
178        formatter
179            .debug_struct("AsyncClient")
180            .field("endpoint", &"[redacted]")
181            .field("credentials", &"[redacted]")
182            .finish_non_exhaustive()
183    }
184}
185
186async fn read_response(
187    response: &mut reqwest::Response,
188    limit: usize,
189) -> Result<SanitizedBuffer, TransportError> {
190    let mut buffered = SanitizedBuffer::with_capacity(limit)
191        .map_err(|_| TransportError::ResponseBodyAllocationFailed)?;
192    loop {
193        let chunk = response
194            .chunk()
195            .await
196            .map_err(|_| TransportError::ResponseReadFailed)?;
197        let Some(chunk) = chunk else { break };
198        buffered
199            .extend_bounded(&chunk, limit)
200            .map_err(|_| TransportError::ResponseTooLarge)?;
201    }
202    Ok(buffered)
203}
204
205fn map_method(method: Method) -> Result<reqwest::Method, TransportError> {
206    reqwest::Method::from_bytes(method.as_str().as_bytes())
207        .map_err(|_| TransportError::MethodRejected)
208}
209
210fn classify_reqwest_error(error: reqwest::Error) -> TransportError {
211    if error.is_timeout() {
212        TransportError::TimedOut
213    } else if error.is_connect() {
214        TransportError::ConnectFailed
215    } else {
216        TransportError::RequestFailed
217    }
218}
cloud_sdk_reqwest/asynchronous/client.rs

cloud_sdk_reqwest/asynchronous/
client.rs
