mcp_memory/
config.rs

1use crate::errors::{MCSError, Result};
2use crate::Transport;
3use std::sync::Arc;
4
5/// How aggressively to push WAL writes to durable storage before acknowledging
6/// the client.
7///
8/// The default [`Async`](Durability::Async) flushes to the kernel page cache
9/// and returns immediately; the background sync thread calls `fsync` within
10/// ~1 second. Journal-mode filesystems (ext4, APFS, NTFS) typically absorb a
11/// power loss within that window.
12///
13/// [`Sync`](Durability::Sync) calls `fsync` before returning, confirming the
14/// data is on stable media. Use this when every write must survive an immediate
15/// power failure, at the cost of higher write latency.
16#[derive(Debug, Clone, Copy, PartialEq, Eq)]
17pub enum Durability {
18    Async,
19    Sync,
20}
21
22impl Durability {
23    pub const fn is_sync(self) -> bool {
24        matches!(self, Durability::Sync)
25    }
26}
27
28impl std::str::FromStr for Durability {
29    type Err = String;
30    fn from_str(s: &str) -> std::result::Result<Self, Self::Err> {
31        match s {
32            "async" | "Async" => Ok(Durability::Async),
33            "sync" | "Sync" => Ok(Durability::Sync),
34            _ => Err(format!("unknown durability '{s}'; expected 'async' or 'sync'")),
35        }
36    }
37}
38
39#[derive(Debug, Clone)]
40pub struct Config {
41    pub memory_file_path: String,
42    pub transport: Transport,
43    pub bind_addr: String,
44    pub durability: Durability,
45    /// Optional bearer token required on the `tcp` and `http` transports. When
46    /// `None`, those transports accept unauthenticated connections (stdio is
47    /// always local and never authenticated).
48    pub auth_token: Option<Arc<str>>,
49    pub mmap_size: i64,
50    pub lru_cache_size: usize,
51    /// Size of the read-only connection pool (concurrent reads). Always >= 1.
52    pub read_pool_size: usize,
53}
54
55impl Config {
56    pub fn from_args(args: &super::Args) -> Result<Self> {
57        let memory_file_path = args
58            .memory_file
59            .clone()
60            .or_else(|| std::env::var("MEMORY_FILE_PATH").ok())
61            .unwrap_or_else(|| "memory.mcpmem".to_string());
62
63        // Resolve the auth token from --auth-token, then --auth-token-file, then
64        // the MCP_MEMORY_AUTH_TOKEN env var. A configured-but-empty token file
65        // is a hard error: fail closed rather than silently disabling auth.
66        let auth_token: Option<Arc<str>> = if let Some(t) = args.auth_token.clone() {
67            Some(Arc::from(t.as_str()))
68        } else if let Some(path) = args.auth_token_file.clone() {
69            let contents = std::fs::read_to_string(&path).map_err(|e| {
70                MCSError::InvalidParams(format!("failed to read --auth-token-file '{path}': {e}"))
71            })?;
72            let token = contents.trim();
73            if token.is_empty() {
74                return Err(MCSError::InvalidParams(format!(
75                    "--auth-token-file '{path}' is empty; refusing to start with auth disabled"
76                )));
77            }
78            Some(Arc::from(token))
79        } else {
80            std::env::var("MCP_MEMORY_AUTH_TOKEN")
81                .ok()
82                .filter(|t| !t.is_empty())
83                .map(|t| Arc::from(t.as_str()))
84        };
85
86        let durability = if let Ok(env) = std::env::var("MCP_MEMORY_DURABILITY") {
87            env.parse().unwrap_or_else(|e| {
88                tracing::warn!("MCP_MEMORY_DURABILITY parse failed: {e}; falling back to Async");
89                Durability::Async
90            })
91        } else {
92            Durability::Async
93        };
94
95        Ok(Config {
96            memory_file_path,
97            transport: args.transport,
98            bind_addr: args.bind.clone(),
99            durability,
100            auth_token,
101            mmap_size: args.mmap_size,
102            lru_cache_size: args.lru_cache_size,
103            read_pool_size: args.read_pool_size.max(1),
104        })
105    }
106}
107
108impl Default for Config {
109    fn default() -> Self {
110        Self {
111            memory_file_path: "memory.mcpmem".to_string(),
112            transport: Transport::Stdio,
113            bind_addr: "127.0.0.1:8080".to_string(),
114            durability: Durability::Async,
115            auth_token: None,
116            mmap_size: 268435456,
117            lru_cache_size: 10000,
118            read_pool_size: 4,
119        }
120    }
121}
122
123
mcp_memory/config.rs

mcp_memory/
config.rs
