samurai 0.1.5

Very early stage user-space P2P network protocol.
Documentation 
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

/// Wrapper to store many buckets
pub mod bucket_list;

use crate::id::Id;
use crate::node::Node;
use std::fmt;
use serde::{Deserialize, Serialize};
use crate::error::BucketError;

#[derive(Serialize, Deserialize)]
pub struct Bucket {
    node_list: Vec<Node>,
    start_id: Id,
    end_id: Id,
    max_nodes: usize,
}

impl Bucket {
    pub fn new(max_nodes: usize, start_id: Id, end_id: Id) -> Self {
        Self {
            node_list: Vec::new(),
            start_id,
            end_id,
            max_nodes,
        }
    }

    /// Add a new ndoe, can fail if the bucket is full, if the node should not
    /// be inside this bucket and if the node is Local but there already is a
    /// local node in this bucket.
    pub fn add_node(&mut self, node: &Node) -> Result<(), BucketError> {
        if self.node_list.len() >= self.max_nodes {
            return Err(BucketError::BucketFull);
        }

        if !self.fits(&node.id()) {
            return Err(BucketError::IncorrectBucket);
        }

        if self.local().is_ok() && node.is_local() {
            return Err(BucketError::RepeatedLNode);
        }

        self.node_list.push(*node);
        Ok(())
    }

    /// Remove a node by its ID
    pub fn rm_node(&mut self, id: Id) {
        if let Some(i) = self.node_list.iter().position(|&i| i.id() == id) {
            self.node_list.remove(i);
        }
    }

    /// Check if the bucket contains the node that represents us
    pub fn local(&self) -> Result<Node, BucketError> {
        for node in self.node_list.iter() {
            if node.is_local() {
                return Ok(*node);
            }
        }

        Err(BucketError::LNodeNotFound)
    }

    /// Divide bucket and split the ID space between the two.
    /// It also moves the nodes to the new bucket if necessary.
    pub fn divide(&mut self) -> Option<Self> {
        if self.node_list.len() >= self.max_nodes {
            println!("Too many nodes");
            return None;
        }

        if self.local().is_err() {
            println!("No local");
            return None;
        }

        // Update the end_id
        let end_id = self.end_id;
        self.end_id = self.end_id.half();

        let mut new_bucket = Bucket::new(self.max_nodes, self.end_id + 1, end_id);

        // Move nodes to corresponding bucket
        let node_list_copy = self.node_list.clone();
        for node in node_list_copy.iter() {
            if new_bucket.add_node(node).is_ok() {
                self.rm_node(node.id())
            }
        }

        Some(new_bucket)
    }

    /// Get a node from the bucket by its index, can fail if index is incorrect.
    pub fn get(&self, i: usize) -> Result<Node, BucketError> {
        if i >= self.node_list.len() {
            return Err(BucketError::IndexError);
        }

        Ok(self.node_list[i])
    }

    /// Get a node from the bucket by its ID.
    pub fn get_by_id(&self, id: &Id) -> Result<Node, BucketError> {
        for node in self.node_list.iter() {
            if node.id() == *id {
                return Ok(*node);
            }
        }

        Err(BucketError::NodeNotFound)
    }

    /// Check if a node fits inside the bucket (in terms of ID)
    pub fn fits(&self, id: &Id) -> bool {
        *id > self.start_id && *id < self.end_id
    }

    /// Get list of nodes inside a bucket
    pub fn nodes(&self) -> &Vec<Node> {
        &self.node_list
    }
}

impl fmt::Debug for Bucket {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        let mut output = format!(
            "{:?}\t{:?}\n\t{:?}",
            self.local().is_ok(),
            self.start_id,
            self.end_id
        );

        for node in self.node_list.iter() {
            output = format!("{}\n\t{:?}", output, node);
        }

        write!(f, "{}\n", output)
    }
}