Add ability to pre-compile modules in wasmtime

Signed-off-by: James Sturtevant <[email protected]>

crates/containerd-shim-wasm/Cargo.toml

@@ -31,6 +31,9 @@ ttrpc = { workspace = true }
 wat = { workspace = true }
 tokio = { version = "1.34.0", features = [ "full" ] }
 futures = { version = "0.3.29" }
+tokio-stream = { version = "0.1" }
+prost-types = "0.11" # should match version in containerd-shim
+sha256 = "1.4.0"
 
 [target.'cfg(unix)'.dependencies]
 caps = "0.5"

crates/containerd-shim-wasm/src/container/context.rs

@@ -42,6 +42,7 @@ pub enum Source<'a> {
     // and they will be included in this array, e.g., a `toml` file with the
     // runtime configuration.
     Oci(&'a [WasmLayer]),
+    Precompiled(&'a WasmLayer),
 }
 
 /// The entrypoint for a WASI module / component.
@@ -79,6 +80,8 @@ impl RuntimeContext for WasiContext<'_> {
 
         let source = if self.wasm_layers.is_empty() {
             Source::File(PathBuf::from(path))
+        } else if self.wasm_layers.len() == 1 && self.wasm_layers[0].precompiled {
+            Source::Precompiled(&self.wasm_layers[0])
         } else {
             Source::Oci(self.wasm_layers)
         };
@@ -337,6 +340,7 @@ mod tests {
             wasm_layers: &[WasmLayer {
                 layer: vec![],
                 config: Descriptor::new(oci_spec::image::MediaType::Other("".to_string()), 10, ""),
+                precompiled: false,
             }],
             platform: &Platform::default(),
         };

crates/containerd-shim-wasm/src/container/engine.rs

@@ -1,7 +1,7 @@
 use std::fs::File;
 use std::io::Read;
 
-use anyhow::{Context, Result};
+use anyhow::{bail, Context, Result};
 
 use super::Source;
 use crate::container::{PathResolve, RuntimeContext};
@@ -26,6 +26,7 @@ pub trait Engine: Clone + Send + Sync + 'static {
         let path = match source {
             Source::File(path) => path,
             Source::Oci(_) => return Ok(()),
+            Source::Precompiled(_) => return Ok(()),
         };
 
         path.resolve_in_path_or_cwd()
@@ -52,4 +53,14 @@ pub trait Engine: Clone + Send + Sync + 'static {
     fn supported_layers_types() -> &'static [&'static str] {
         &["application/vnd.bytecodealliance.wasm.component.layer.v0+wasm"]
     }
+
+    /// Precomiple a module
+    fn precompile(&self, _layers: &[Vec<u8>]) -> Result<Vec<u8>> {
+        bail!("precompilation not supported for this runtime")
+    }
+
+    /// Precomiple a module
+    fn can_precompile() -> bool {
+        false
+    }
 }