qiniu_http_client/client/resolver/
shuffled.rs

1use super::{ResolveOptions, ResolveResult, Resolver};
2use rand::{prelude::*, thread_rng};
3
4#[cfg(feature = "async")]
5use futures::future::BoxFuture;
6
7/// 域名解析随机混淆器
8///
9/// 基于一个域名解析器实例，但将其返回的解析结果打乱
10#[derive(Debug, Default, Clone)]
11pub struct ShuffledResolver<R: ?Sized> {
12    base_resolver: R,
13}
14
15impl<R> ShuffledResolver<R> {
16    /// 创建域名解析随机混淆器
17    #[inline]
18    pub const fn new(base_resolver: R) -> Self {
19        Self { base_resolver }
20    }
21}
22
23impl<R: Resolver + Clone> Resolver for ShuffledResolver<R> {
24    #[inline]
25    fn resolve(&self, domain: &str, opts: ResolveOptions) -> ResolveResult {
26        let mut answers = self.base_resolver.resolve(domain, opts)?;
27        answers.ip_addrs_mut().shuffle(&mut thread_rng());
28        Ok(answers)
29    }
30
31    #[inline]
32    #[cfg(feature = "async")]
33    #[cfg_attr(feature = "docs", doc(cfg(feature = "async")))]
34    fn async_resolve<'a>(&'a self, domain: &'a str, opts: ResolveOptions<'a>) -> BoxFuture<'a, ResolveResult> {
35        Box::pin(async move {
36            let mut answers = self.base_resolver.async_resolve(domain, opts).await?;
37            answers.ip_addrs_mut().shuffle(&mut thread_rng());
38            Ok(answers)
39        })
40    }
41}
42
43#[cfg(test)]
44mod tests {
45    use super::*;
46    use crate::test_utils::make_static_resolver;
47    use std::{
48        collections::HashSet,
49        error::Error,
50        net::{IpAddr, Ipv4Addr},
51        result::Result,
52    };
53
54    const IPS: &[IpAddr] = &[
55        IpAddr::V4(Ipv4Addr::new(1, 1, 1, 1)),
56        IpAddr::V4(Ipv4Addr::new(2, 2, 2, 2)),
57        IpAddr::V4(Ipv4Addr::new(3, 3, 3, 3)),
58    ];
59
60    #[test]
61    fn test_shuffled_resolver() -> Result<(), Box<dyn Error>> {
62        let resolver = ShuffledResolver::new(make_static_resolver(IPS.to_vec().into()));
63        let ips = resolver.resolve("testdomain.com", Default::default())?;
64        assert_eq!(make_set(ips.ip_addrs()), make_set(IPS));
65        Ok(())
66    }
67
68    fn make_set(ips: impl AsRef<[IpAddr]>) -> HashSet<IpAddr> {
69        let mut h = HashSet::new();
70        h.extend(ips.as_ref());
71        h
72    }
73}
qiniu_http_client/client/resolver/shuffled.rs

qiniu_http_client/client/resolver/
shuffled.rs
