cachekit/backend/
cachekitio_ttl.rs

1//! [`TtlInspectable`] implementation for the cachekit.io HTTP backend.
2
3use std::time::Duration;
4
5use async_trait::async_trait;
6use serde::{Deserialize, Serialize};
7
8use super::cachekitio::{reqwest_err_sanitized, CachekitIO};
9use super::TtlInspectable;
10use crate::error::BackendError;
11
12#[derive(Deserialize)]
13#[serde(deny_unknown_fields)]
14struct TtlResponse {
15    ttl: Option<u64>,
16}
17
18#[derive(Serialize)]
19struct RefreshTtlRequest {
20    ttl: u64,
21}
22
23#[cfg(not(target_arch = "wasm32"))]
24#[cfg_attr(not(feature = "unsync"), async_trait)]
25#[cfg_attr(feature = "unsync", async_trait(?Send))]
26impl TtlInspectable for CachekitIO {
27    async fn ttl(&self, key: &str) -> Result<Option<Duration>, BackendError> {
28        let url = self.ttl_url(key)?;
29
30        let req =
31            self.with_standard_headers(self.client().get(&url).bearer_auth(self.api_key_str()));
32
33        let resp = req
34            .send()
35            .await
36            .map_err(|e| reqwest_err_sanitized(e, self.api_key_str()))?;
37
38        match resp.status().as_u16() {
39            200 => {
40                let body: TtlResponse = resp.json().await.map_err(|e| {
41                    BackendError::transient(format!("failed to parse TTL response: {e}"))
42                })?;
43                Ok(body.ttl.map(Duration::from_secs))
44            }
45            404 => Ok(None),
46            _ => Err(self.error_from_response(resp).await),
47        }
48    }
49
50    async fn refresh_ttl(&self, key: &str, ttl: Duration) -> Result<bool, BackendError> {
51        let secs = ttl.as_secs();
52        if secs == 0 {
53            return Err(BackendError::permanent(
54                "refresh_ttl requires at least 1 second".to_string(),
55            ));
56        }
57
58        let url = self.ttl_url(key)?;
59
60        let body = serde_json::to_vec(&RefreshTtlRequest { ttl: secs }).map_err(|e| {
61            BackendError::permanent(format!("failed to serialize refresh_ttl request: {e}"))
62        })?;
63
64        let req = self.with_standard_headers(
65            self.client()
66                .patch(&url)
67                .bearer_auth(self.api_key_str())
68                .header("Content-Type", "application/json")
69                .body(body),
70        );
71
72        let resp = req
73            .send()
74            .await
75            .map_err(|e| reqwest_err_sanitized(e, self.api_key_str()))?;
76
77        match resp.status().as_u16() {
78            200 | 204 => Ok(true),
79            404 => Ok(false),
80            _ => Err(self.error_from_response(resp).await),
81        }
82    }
83}
84
85#[cfg(test)]
86mod tests {
87    use super::*;
88
89    /// Compile-time proof that CachekitIO implements TtlInspectable.
90    fn _assert_ttl_inspectable(_b: &dyn TtlInspectable) {}
91
92    #[test]
93    fn cachekitio_is_ttl_inspectable() {
94        fn _check(backend: &CachekitIO) {
95            _assert_ttl_inspectable(backend);
96        }
97    }
98
99    /// The server answers `{"ttl": null}` for a live key with no expiry.
100    /// That must decode to `None`, never a parse error.
101    #[test]
102    fn ttl_response_decodes_null_ttl_as_none() {
103        let decode = |json: &str| serde_json::from_str::<TtlResponse>(json).map(|r| r.ttl);
104
105        assert!(matches!(decode(r#"{"ttl":null}"#), Ok(None)));
106        assert!(matches!(decode(r#"{"ttl":42}"#), Ok(Some(42))));
107        assert!(decode(r#"{"ttl":null,"extra":1}"#).is_err());
108    }
109}
cachekit/backend/cachekitio_ttl.rs

cachekit/backend/
cachekitio_ttl.rs
