model_context_protocol/
transport_factory.rs

1//! Transport factory for creating MCP transports from configuration.
2//!
3//! This module provides a unified interface for creating transports based on
4//! `McpServerConnectionConfig`, eliminating duplicate transport creation logic
5//! in hub.rs and server_hub.rs.
6
7use std::sync::Arc;
8use std::time::Duration;
9
10use crate::client::http::HttpTransportAdapter;
11use crate::client::stdio::StdioTransportAdapter;
12use crate::transport::{
13    McpServerConnectionConfig, McpTransport, McpTransportError, TransportTypeId,
14};
15
16/// Factory for creating MCP transports from configuration.
17pub struct TransportFactory;
18
19impl TransportFactory {
20    /// Create a transport from a connection configuration.
21    ///
22    /// Returns a boxed transport trait object that can be used for communication.
23    ///
24    /// # Errors
25    ///
26    /// Returns an error if:
27    /// - Stdio transport is missing command
28    /// - HTTP transport is missing URL
29    /// - Transport creation fails
30    pub async fn create(
31        config: &McpServerConnectionConfig,
32    ) -> Result<Arc<dyn McpTransport>, McpTransportError> {
33        match config.transport {
34            TransportTypeId::Stdio => Self::create_stdio(config).await,
35            TransportTypeId::Http => Self::create_http(config).await,
36        }
37    }
38
39    /// Create a stdio transport.
40    async fn create_stdio(
41        config: &McpServerConnectionConfig,
42    ) -> Result<Arc<dyn McpTransport>, McpTransportError> {
43        let command = config.command.as_ref().ok_or_else(|| {
44            McpTransportError::TransportError("Stdio transport requires command".to_string())
45        })?;
46
47        let timeout = Duration::from_secs(config.timeout_secs);
48
49        let transport = StdioTransportAdapter::connect_with_env(
50            command,
51            &config.args,
52            config.env.clone(),
53            Some(config.config.clone()),
54            timeout,
55        )
56        .await?;
57
58        Ok(Arc::new(transport))
59    }
60
61    /// Create an HTTP transport.
62    async fn create_http(
63        config: &McpServerConnectionConfig,
64    ) -> Result<Arc<dyn McpTransport>, McpTransportError> {
65        let url = config.url.as_ref().ok_or_else(|| {
66            McpTransportError::TransportError("HTTP transport requires URL".to_string())
67        })?;
68
69        let timeout = Duration::from_secs(config.timeout_secs);
70        let transport = HttpTransportAdapter::with_timeout(url, timeout)?;
71
72        Ok(Arc::new(transport))
73    }
74
75    /// Check if a transport type is supported.
76    pub fn is_supported(transport_type: TransportTypeId) -> bool {
77        matches!(
78            transport_type,
79            TransportTypeId::Stdio | TransportTypeId::Http
80        )
81    }
82
83    /// List supported transport types.
84    pub fn supported_types() -> Vec<TransportTypeId> {
85        vec![TransportTypeId::Stdio, TransportTypeId::Http]
86    }
87}
88
89#[cfg(test)]
90mod tests {
91    use super::*;
92
93    #[test]
94    fn test_is_supported() {
95        assert!(TransportFactory::is_supported(TransportTypeId::Stdio));
96        assert!(TransportFactory::is_supported(TransportTypeId::Http));
97    }
98
99    #[test]
100    fn test_supported_types() {
101        let types = TransportFactory::supported_types();
102        assert!(types.contains(&TransportTypeId::Stdio));
103        assert!(types.contains(&TransportTypeId::Http));
104    }
105}
model_context_protocol/transport_factory.rs

model_context_protocol/
transport_factory.rs
