libp2p_kad/
addresses.rs

1// Copyright 2019 Parity Technologies (UK) Ltd.
2//
3// Permission is hereby granted, free of charge, to any person obtaining a
4// copy of this software and associated documentation files (the "Software"),
5// to deal in the Software without restriction, including without limitation
6// the rights to use, copy, modify, merge, publish, distribute, sublicense,
7// and/or sell copies of the Software, and to permit persons to whom the
8// Software is furnished to do so, subject to the following conditions:
9//
10// The above copyright notice and this permission notice shall be included in
11// all copies or substantial portions of the Software.
12//
13// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
14// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
15// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
16// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
17// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
18// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
19// DEALINGS IN THE SOFTWARE.
20
21use libp2p_core::Multiaddr;
22use smallvec::SmallVec;
23use std::fmt;
24
25/// A non-empty list of (unique) addresses of a peer in the routing table.
26/// Every address must be a fully-qualified /p2p address.
27#[derive(Clone)]
28pub struct Addresses {
29    addrs: SmallVec<[Multiaddr; 6]>,
30}
31
32#[allow(clippy::len_without_is_empty)]
33impl Addresses {
34    /// Creates a new list of addresses.
35    pub fn new(addr: Multiaddr) -> Addresses {
36        let mut addrs = SmallVec::new();
37        addrs.push(addr);
38        Addresses { addrs }
39    }
40
41    /// Gets a reference to the first address in the list.
42    pub fn first(&self) -> &Multiaddr {
43        &self.addrs[0]
44    }
45
46    /// Returns an iterator over the addresses.
47    pub fn iter(&self) -> impl Iterator<Item = &Multiaddr> {
48        self.addrs.iter()
49    }
50
51    /// Returns the number of addresses in the list.
52    pub fn len(&self) -> usize {
53        self.addrs.len()
54    }
55
56    /// Converts the addresses into a `Vec`.
57    pub fn into_vec(self) -> Vec<Multiaddr> {
58        self.addrs.into_vec()
59    }
60
61    /// Removes the given address from the list.
62    ///
63    /// Returns `Ok(())` if the address is either not in the list or was found and
64    /// removed. Returns `Err(())` if the address is the last remaining address,
65    /// which cannot be removed.
66    ///
67    /// An address should only be removed if is determined to be invalid or
68    /// otherwise unreachable.
69    #[allow(clippy::result_unit_err)]
70    pub fn remove(&mut self, addr: &Multiaddr) -> Result<(), ()> {
71        if self.addrs.len() == 1 && self.addrs[0] == *addr {
72            return Err(());
73        }
74
75        if let Some(pos) = self.addrs.iter().position(|a| a == addr) {
76            self.addrs.remove(pos);
77            if self.addrs.len() <= self.addrs.inline_size() {
78                self.addrs.shrink_to_fit();
79            }
80        }
81
82        Ok(())
83    }
84
85    /// Adds a new address to the end of the list.
86    ///
87    /// Returns true if the address was added, false otherwise (i.e. if the
88    /// address is already in the list).
89    pub fn insert(&mut self, addr: Multiaddr) -> bool {
90        if self.addrs.iter().all(|a| *a != addr) {
91            self.addrs.push(addr);
92            true
93        } else {
94            false
95        }
96    }
97
98    /// Replaces an old address with a new address.
99    ///
100    /// Returns true if the previous address was found and replaced with a clone
101    /// of the new address, returns false otherwise.
102    pub fn replace(&mut self, old: &Multiaddr, new: &Multiaddr) -> bool {
103        if let Some(a) = self.addrs.iter_mut().find(|a| *a == old) {
104            *a = new.clone();
105            return true;
106        }
107
108        false
109    }
110}
111
112impl fmt::Debug for Addresses {
113    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
114        f.debug_list().entries(self.addrs.iter()).finish()
115    }
116}
117
118#[cfg(test)]
119mod tests {
120    use super::*;
121
122    #[test]
123    fn given_one_address_when_removing_different_one_returns_ok() {
124        let mut addresses = make_addresses([tcp_addr(1234)]);
125
126        let result = addresses.remove(&tcp_addr(4321));
127
128        assert!(result.is_ok());
129        assert_eq!(
130            addresses.into_vec(),
131            vec![tcp_addr(1234)],
132            "`Addresses` to not change because we tried to remove a non-present address"
133        );
134    }
135
136    #[test]
137    fn given_one_address_when_removing_correct_one_returns_err() {
138        let mut addresses = make_addresses([tcp_addr(1234)]);
139
140        let result = addresses.remove(&tcp_addr(1234));
141
142        assert!(result.is_err());
143        assert_eq!(
144            addresses.into_vec(),
145            vec![tcp_addr(1234)],
146            "`Addresses` to not be empty because it would have been the last address to be removed"
147        );
148    }
149
150    #[test]
151    fn given_many_addresses_when_removing_different_one_does_not_remove_and_returns_ok() {
152        let mut addresses = make_addresses([tcp_addr(1234), tcp_addr(4321)]);
153
154        let result = addresses.remove(&tcp_addr(5678));
155
156        assert!(result.is_ok());
157        assert_eq!(
158            addresses.into_vec(),
159            vec![tcp_addr(1234), tcp_addr(4321)],
160            "`Addresses` to not change because we tried to remove a non-present address"
161        );
162    }
163
164    #[test]
165    fn given_many_addresses_when_removing_correct_one_removes_and_returns_ok() {
166        let mut addresses = make_addresses([tcp_addr(1234), tcp_addr(4321)]);
167
168        let result = addresses.remove(&tcp_addr(1234));
169
170        assert!(result.is_ok());
171        assert_eq!(
172            addresses.into_vec(),
173            vec![tcp_addr(4321)],
174            "`Addresses to no longer contain address was present and then removed`"
175        );
176    }
177
178    /// Helper function to easily initialize Addresses struct with multiple addresses.
179    fn make_addresses(addresses: impl IntoIterator<Item = Multiaddr>) -> Addresses {
180        Addresses {
181            addrs: SmallVec::from_iter(addresses),
182        }
183    }
184
185    /// Helper function to create a tcp Multiaddr with a specific port
186    fn tcp_addr(port: u16) -> Multiaddr {
187        format!("/ip4/127.0.0.1/tcp/{port}").parse().unwrap()
188    }
189}
libp2p_kad/addresses.rs

libp2p_kad/
addresses.rs
