d_engine/config/
cluster.rs

1use std::net::SocketAddr;
2use std::path::PathBuf;
3
4use serde::Deserialize;
5use serde::Serialize;
6
7use crate::proto::NodeMeta;
8use crate::Error;
9use crate::Result;
10use crate::FOLLOWER;
11
12/// Cluster node configuration parameters
13///
14/// Encapsulates all essential settings for cluster node initialization and operation,
15/// including network settings, storage paths, and cluster topology.
16///
17/// # Defaults
18/// Configuration can be loaded from file with default values generated via `serde`'s
19/// default implementations. Field-level defaults use helper functions prefixed with `default_`.
20
21#[derive(Debug, Serialize, Deserialize, Clone)]
22pub struct ClusterConfig {
23    /// Unique node identifier in cluster
24    ///
25    /// Default: `default_node_id()` (typically 0 for single-node setup)
26    #[serde(default = "default_node_id")]
27    pub node_id: u32,
28
29    /// Network listening address (IP:PORT)
30    ///
31    /// Default: `default_listen_addr()` (127.0.0.1:8000)
32    #[serde(default = "default_listen_addr")]
33    pub listen_address: SocketAddr,
34
35    /// Seed nodes for cluster initialization
36    ///
37    /// Default: `default_initial_cluster()` (empty vector)
38    ///
39    /// # Note
40    /// Should contain at least 3 nodes for production deployment
41    #[serde(default = "default_initial_cluster")]
42    pub initial_cluster: Vec<NodeMeta>,
43
44    /// Database storage root directory
45    ///
46    /// Default: `default_db_dir()` (./data/db)
47    #[serde(default = "default_db_dir")]
48    pub db_root_dir: PathBuf,
49
50    /// Log files output directory
51    ///
52    /// Default: `default_log_dir()` (./logs)
53    #[serde(default = "default_log_dir")]
54    pub log_dir: PathBuf,
55}
56impl Default for ClusterConfig {
57    fn default() -> Self {
58        Self {
59            node_id: default_node_id(),
60            listen_address: default_listen_addr(),
61            initial_cluster: vec![],
62            db_root_dir: default_db_dir(),
63            log_dir: default_log_dir(),
64        }
65    }
66}
67
68impl ClusterConfig {
69    /// Validates cluster configuration consistency
70    /// # Errors
71    /// Returns `Error::InvalidConfig` if any configuration rules are violated
72    pub fn validate(&self) -> Result<()> {
73        // Validate node identity
74        if self.node_id == 0 {
75            return Err(Error::InvalidConfig(
76                "node_id cannot be 0 (reserved for invalid nodes)".into(),
77            ));
78        }
79
80        // Validate cluster membership
81        if self.initial_cluster.is_empty() {
82            return Err(Error::InvalidConfig(
83                "initial_cluster must contain at least one node".into(),
84            ));
85        }
86
87        // Check node existence in cluster
88        let self_in_cluster = self.initial_cluster.iter().any(|n| n.id == self.node_id);
89        if !self_in_cluster {
90            return Err(Error::InvalidConfig(format!(
91                "Current node {} not found in initial_cluster",
92                self.node_id
93            )));
94        }
95
96        // Check unique node IDs
97        let mut ids = std::collections::HashSet::new();
98        for node in &self.initial_cluster {
99            if !ids.insert(node.id) {
100                return Err(Error::InvalidConfig(format!(
101                    "Duplicate node_id {} in initial_cluster",
102                    node.id
103                )));
104            }
105        }
106
107        // Validate network configuration
108        if self.listen_address.port() == 0 {
109            return Err(Error::InvalidConfig(
110                "listen_address must specify a non-zero port".into(),
111            ));
112        }
113
114        // Validate storage paths
115        self.validate_directory(&self.db_root_dir, "db_root_dir")?;
116        self.validate_directory(&self.log_dir, "log_dir")?;
117
118        Ok(())
119    }
120
121    /// Ensures directory path is valid and writable
122    fn validate_directory(
123        &self,
124        path: &PathBuf,
125        name: &str,
126    ) -> Result<()> {
127        if path.as_os_str().is_empty() {
128            return Err(Error::InvalidConfig(format!("{} path cannot be empty", name)));
129        }
130
131        #[cfg(not(test))]
132        {
133            use std::fs;
134            // Check directory existence or create ability
135            if !path.exists() {
136                fs::create_dir_all(path).map_err(|e| {
137                    Error::InvalidConfig(format!(
138                        "Failed to create {} directory at {}: {}",
139                        name,
140                        path.display(),
141                        e
142                    ))
143                })?;
144            }
145
146            // Check write permissions
147            let test_file = path.join(".permission_test");
148            fs::write(&test_file, b"test").map_err(|e| {
149                Error::InvalidConfig(format!(
150                    "No write permission in {} directory {}: {}",
151                    name,
152                    path.display(),
153                    e
154                ))
155            })?;
156            fs::remove_file(&test_file).ok();
157        }
158
159        Ok(())
160    }
161}
162
163fn default_node_id() -> u32 {
164    1
165}
166fn default_initial_cluster() -> Vec<NodeMeta> {
167    vec![NodeMeta {
168        id: 1,
169        ip: "127.0.0.1".to_string(),
170        port: 8080,
171        role: FOLLOWER,
172    }]
173}
174fn default_listen_addr() -> SocketAddr {
175    "127.0.0.1:9081".parse().unwrap()
176}
177fn default_db_dir() -> PathBuf {
178    PathBuf::from("/tmp/db")
179}
180fn default_log_dir() -> PathBuf {
181    PathBuf::from("/tmp/logs")
182}
d_engine/config/cluster.rs

d_engine/config/
cluster.rs
