Implement basic request caching for compilation server (#1253)

* Implement basic request caching for compilation server

* Fix formatting

node-graph/compilation-server/src/main.rs

@@ -1,4 +1,4 @@
-use std::sync::Arc;
+use std::{collections::HashMap, sync::Arc, sync::RwLock};
 
 use gpu_compiler_bin_wrapper::CompileRequest;
 use tower_http::cors::CorsLayer;
@@ -12,12 +12,14 @@ use axum::{
 
 struct AppState {
 	compile_dir: tempfile::TempDir,
+	cache: RwLock<HashMap<CompileRequest, Result<Vec<u8>, StatusCode>>>,
 }
 
 #[tokio::main]
 async fn main() {
 	let shared_state = Arc::new(AppState {
 		compile_dir: tempfile::tempdir().expect("failed to create tempdir"),
+		cache: Default::default(),
 	});
 
 	// build our application with a single route
@@ -33,9 +35,15 @@ async fn main() {
 }
 
 async fn post_compile_spirv(State(state): State<Arc<AppState>>, Json(compile_request): Json<CompileRequest>) -> Result<Vec<u8>, StatusCode> {
+	if let Some(result) = state.cache.read().unwrap().get(&compile_request) {
+		return result.clone();
+	}
+
 	let path = std::env::var("CARGO_MANIFEST_DIR").unwrap() + "/../gpu-compiler/Cargo.toml";
-	compile_request.compile(state.compile_dir.path().to_str().expect("non utf8 tempdir path"), &path).map_err(|e| {
+	let result = compile_request.compile(state.compile_dir.path().to_str().expect("non utf8 tempdir path"), &path).map_err(|e| {
 		eprintln!("compilation failed: {}", e);
 		StatusCode::INTERNAL_SERVER_ERROR
-	})
+	});
+	state.cache.write().unwrap().insert(compile_request, result.clone());
+	result
 }

node-graph/gpu-compiler/gpu-compiler-bin-wrapper/src/lib.rs

@@ -41,7 +41,7 @@ pub fn compile_spirv(request: &CompileRequest, compile_dir: Option<&str>, manife
 	Ok(std::fs::read(compile_dir.unwrap().to_owned() + "/shader.spv")?)
 }
 
-#[derive(Serialize, Deserialize, Debug, Clone, PartialEq)]
+#[derive(Serialize, Deserialize, Debug, Clone, PartialEq, Hash, Eq)]
 pub struct CompileRequest {
 	networks: Vec<graph_craft::proto::ProtoNetwork>,
 	input_types: Vec<Type>,

node-graph/graph-craft/src/proto.rs

@@ -23,7 +23,7 @@ pub type TypeErasedPinned<'n> = Pin<Box<dyn for<'i> NodeIO<'i, Any<'i>, Output =
 pub type NodeConstructor = for<'a> fn(Vec<TypeErasedPinnedRef<'static>>) -> DynFuture<'static, TypeErasedPinned<'static>>;
 
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[derive(Debug, Default, PartialEq, Clone)]
+#[derive(Debug, Default, PartialEq, Clone, Hash, Eq)]
 pub struct ProtoNetwork {
 	// Should a proto Network even allow inputs? Don't think so
 	pub inputs: Vec<NodeId>,
@@ -90,12 +90,23 @@ pub enum ConstructionArgs {
 	Inline(InlineRust),
 }
 
+impl Eq for ConstructionArgs {}
+
 impl PartialEq for ConstructionArgs {
 	fn eq(&self, other: &Self) -> bool {
 		match (&self, &other) {
 			(Self::Nodes(n1), Self::Nodes(n2)) => n1 == n2,
 			(Self::Value(v1), Self::Value(v2)) => v1 == v2,
-			_ => core::mem::discriminant(self) == core::mem::discriminant(other),
+			_ => {
+				use std::hash::Hasher;
+				use xxhash_rust::xxh3::Xxh3;
+				let hash = |input: &Self| {
+					let mut hasher = Xxh3::new();
+					input.hash(&mut hasher);
+					hasher.finish()
+				};
+				hash(self) == hash(other)
+			}
 		}
 	}
 }
@@ -126,7 +137,7 @@ impl ConstructionArgs {
 }
 
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
-#[derive(Debug, PartialEq, Clone)]
+#[derive(Debug, PartialEq, Clone, Hash, Eq)]
 pub struct ProtoNode {
 	pub construction_args: ConstructionArgs,
 	pub input: ProtoNodeInput,
@@ -137,7 +148,7 @@ pub struct ProtoNode {
 /// A ProtoNodeInput represents the input of a node in a ProtoNetwork.
 /// For documentation on the meaning of the variants, see the documentation of the `NodeInput` enum
 /// in the `document` module
-#[derive(Debug, PartialEq, Eq, Clone)]
+#[derive(Debug, PartialEq, Eq, Clone, Hash)]
 #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
 pub enum ProtoNodeInput {
 	None,