camel_component_wasm/
lib.rs

1//! WebAssembly component for rust-camel — executes WASM modules as route processors via a Wasmtime runtime.
2//!
3//! Main types: `WasmComponent`, `WasmBundle`, `WasmConfig`, `WasmEndpoint`, `StateStore`.
4//! Main modules: `runtime`, `bindings`, `state_store`, `host_functions`.
5//!
6//! # Limitations
7//!
8//! - Only the [Wasmtime](https://wasmtime.dev) runtime is supported; other WASM runtimes
9//!   (Wasmer, WasmEdge, etc.) are not compatible.
10//! - WASM modules must export a specific interface defined by `camel_wasm_bindings`; arbitrary
11//!   WASM binaries cannot be dropped in without meeting this contract.
12//! - The WASM sandbox has no access to the host filesystem or network by default;
13//!   host functions are limited to what is explicitly exposed via `host_functions`.
14//! - Epoch-based fuel/interruption requires the `epoch` feature; long-running modules
15//!   without epoch support may block the async executor.
16
17pub mod authorization_policy;
18pub mod bean;
19pub mod bean_bindings;
20pub mod bindings;
21pub mod bundle;
22pub mod config;
23pub mod endpoint;
24pub mod epoch;
25pub mod error;
26pub mod health;
27pub mod host_functions;
28pub mod producer;
29pub mod runtime;
30pub mod security_policy;
31pub mod security_policy_bindings;
32pub mod serde_bridge;
33pub mod state_store;
34pub mod wasm_plugin_context;
35
36pub use authorization_policy::{WasmAuthorizationPolicyEvaluator, build_permission_registry};
37pub use bundle::WasmBundle;
38pub use config::WasmConfig;
39pub use endpoint::WasmEndpoint;
40pub use epoch::EpochTicker;
41pub use error::{TrapReason, WasmError};
42pub use health::WasmHealthCheck;
43pub use security_policy::{WasmSecurityPolicy, build_security_policy_registry};
44pub use state_store::StateStore;
45
46use std::path::PathBuf;
47use std::sync::Arc;
48use std::sync::atomic::AtomicBool;
49
50use camel_api::CamelError;
51use camel_component_api::{Component, ComponentContext, Endpoint};
52use camel_core::Registry;
53
54pub struct WasmComponent {
55    registry: Arc<std::sync::Mutex<Registry>>,
56    base_dir: PathBuf,
57    engine_loaded: Arc<AtomicBool>,
58}
59
60impl WasmComponent {
61    pub fn new(registry: Arc<std::sync::Mutex<Registry>>, base_dir: PathBuf) -> Self {
62        Self {
63            registry,
64            base_dir,
65            // TODO: set to true when WASM module is successfully loaded/instantiated
66            engine_loaded: Arc::new(AtomicBool::new(false)),
67        }
68    }
69
70    fn validate_and_resolve_path(&self, uri_path: &str) -> Result<PathBuf, CamelError> {
71        if PathBuf::from(uri_path).is_absolute() {
72            return Err(CamelError::InvalidUri(
73                "WASM path must be relative (not absolute)".to_string(),
74            ));
75        }
76
77        if PathBuf::from(uri_path)
78            .components()
79            .any(|c| matches!(c, std::path::Component::ParentDir))
80        {
81            return Err(CamelError::InvalidUri(
82                "WASM path must not contain '..'".to_string(),
83            ));
84        }
85
86        let resolved = self.base_dir.join(uri_path);
87        let canonical = resolved.canonicalize().map_err(|_| {
88            CamelError::ComponentNotFound(format!("WASM module not found: {}", resolved.display()))
89        })?;
90
91        let canonical_base = self.base_dir.canonicalize().map_err(|_| {
92            CamelError::EndpointCreationFailed(format!(
93                "failed to resolve base directory: {}",
94                self.base_dir.display()
95            ))
96        })?;
97
98        if !canonical.starts_with(&canonical_base) {
99            return Err(CamelError::InvalidUri(
100                "WASM path escapes project root".to_string(),
101            ));
102        }
103
104        Ok(canonical)
105    }
106}
107
108impl Component for WasmComponent {
109    fn scheme(&self) -> &str {
110        "wasm"
111    }
112
113    fn create_endpoint(
114        &self,
115        uri: &str,
116        ctx: &dyn ComponentContext,
117    ) -> Result<Box<dyn Endpoint>, CamelError> {
118        let uri_without_scheme = uri.strip_prefix("wasm:").ok_or_else(|| {
119            CamelError::InvalidUri(format!("WASM URI must start with 'wasm:': {uri}"))
120        })?;
121
122        let (path_part, wasm_config) = crate::config::WasmConfig::from_uri(uri_without_scheme);
123        if path_part.is_empty() {
124            return Err(CamelError::InvalidUri(
125                "WASM URI must include a module path".to_string(),
126            ));
127        }
128
129        let module_path = self.validate_and_resolve_path(&path_part)?;
130
131        let health_check = WasmHealthCheck::new(Arc::clone(&self.engine_loaded));
132        ctx.register_current_route_health_check(Arc::new(health_check));
133
134        Ok(Box::new(WasmEndpoint::new(
135            uri.to_string(),
136            module_path,
137            self.registry.clone(),
138            wasm_config,
139        )))
140    }
141}
camel_component_wasm/lib.rs

camel_component_wasm/
lib.rs
