feat: Adds query sdk proc-macro.

Cargo.toml

@@ -20,6 +20,7 @@ members = [
     "plugins/dummy_sha256",
     "plugins/dummy_sha256_sdk",
     "sdk/rust",
+    "hipcheck-sdk-macros",
 ]
 
 # Make sure Hipcheck is run with `cargo run`.

hipcheck-sdk-macros/Cargo.toml

@@ -0,0 +1,17 @@
+[package]
+name = "hipcheck-sdk-macros"
+description = "Helper macros for the `hipcheck-sdk` crate."
+repository = "https://github.com/mitre/hipcheck"
+version = "0.1.0"
+edition = "2021"
+license = "Apache-2.0"
+
+[lib]
+proc-macro = true
+
+[dependencies]
+anyhow = "1.0.89"
+convert_case = "0.6.0"
+proc-macro2 = "1.0.86"
+quote = "1.0.37"
+syn = { version = "2.0.77", features = ["full", "printing"] }

hipcheck-sdk-macros/src/lib.rs

@@ -0,0 +1,240 @@
+// SPDX-License-Identifier: Apache-2.0
+
+use convert_case::Casing;
+use proc_macro::TokenStream;
+use proc_macro2::Span;
+use std::ops::Not;
+use std::sync::{LazyLock, Mutex};
+use syn::spanned::Spanned;
+use syn::{parse_macro_input, Error, Ident, ItemFn, Meta, PatType};
+
+static QUERIES: LazyLock<Mutex<Vec<NamedQuerySpec>>> = LazyLock::new(|| Mutex::new(vec![]));
+
+#[allow(unused)]
+#[derive(Debug, Clone)]
+struct NamedQuerySpec {
+	pub struct_name: String,
+	pub function: String,
+	pub default: bool,
+}
+
+struct QuerySpec {
+	pub function: Ident,
+	pub input_type: syn::Type,
+	pub output_type: syn::Type,
+	pub default: bool,
+}
+
+/// Parse Path to confirm that it represents a Result<T: Serialize> and return the type T
+fn parse_result_generic(p: &syn::Path) -> Result<syn::Type, Error> {
+	use syn::GenericArgument;
+	use syn::PathArguments;
+	// Assert it is a Result
+	// Panic: Safe to unwrap because there should be at least one element in the sequence
+	let last = p.segments.last().unwrap();
+	if last.ident != "Result" {
+		return Err(Error::new(
+			p.span(),
+			"Expected return type to be a Result<T: Serialize>",
+		));
+	}
+	match &last.arguments {
+		PathArguments::AngleBracketed(x) => {
+			let Some(GenericArgument::Type(ty)) = x.args.first() else {
+				return Err(Error::new(
+					p.span(),
+					"Expected return type to be a Result<T: Serialize>",
+				));
+			};
+			Ok(ty.clone())
+		}
+		_ => Err(Error::new(
+			p.span(),
+			"Expected return type to be a Result<T: Serialize>",
+		)),
+	}
+}
+
+/// Parse PatType to confirm that it contains a &mut PluginEngine
+fn parse_plugin_engine(engine_arg: &PatType) -> Result<(), Error> {
+	if let syn::Type::Reference(type_reference) = engine_arg.ty.as_ref() {
+		if type_reference.mutability.is_some() {
+			if let syn::Type::Path(type_path) = type_reference.elem.as_ref() {
+				let last = type_path.path.segments.last().unwrap();
+				if last.ident == "PluginEngine" {
+					return Ok(());
+				}
+			}
+		}
+	}
+
+	Err(Error::new(
+		engine_arg.span(),
+		"The first argument of the query function must be a &mut PluginEngine",
+	))
+}
+
+fn parse_named_query_spec(opt_meta: Option<Meta>, item_fn: ItemFn) -> Result<QuerySpec, Error> {
+	use syn::Meta::*;
+	use syn::ReturnType;
+	let sig = &item_fn.sig;
+
+	let function = sig.ident.clone();
+
+	let input_type: syn::Type = {
+		let inputs = &sig.inputs;
+		if inputs.len() != 2 {
+			return Err(Error::new(item_fn.span(), "Query function must take two arguments: &mut PluginEngine, and an input type that implements Serialize"));
+		}
+		// Validate that the first arg is type &mut PluginEngine
+		if let Some(syn::FnArg::Typed(engine_arg)) = inputs.get(0) {
+			parse_plugin_engine(engine_arg)?;
+		}
+
+		if let Some(input_arg) = inputs.get(1) {
+			let syn::FnArg::Typed(input_arg_info) = input_arg else {
+				return Err(Error::new(item_fn.span(), "Query function must take two arguments: &mut PluginEngine, and an input type that implements Serialize"));
+			};
+			input_arg_info.ty.as_ref().clone()
+		} else {
+			return Err(Error::new(item_fn.span(), "Query function must take two arguments: &mut PluginEngine, and an input type that implements Serialize"));
+		}
+	};
+
+	let output_type = match &sig.output {
+		ReturnType::Default => {
+			return Err(Error::new(
+				item_fn.span(),
+				"Query function must return Result<T: Serialize>",
+			));
+		}
+		ReturnType::Type(_, b_type) => {
+			use syn::Type;
+			match b_type.as_ref() {
+				Type::Path(p) => parse_result_generic(&p.path)?,
+				_ => {
+					return Err(Error::new(
+						item_fn.span(),
+						"Query function must return Result<T: Serialize>",
+					))
+				}
+			}
+		}
+	};
+
+	let default = match opt_meta {
+		Some(NameValue(nv)) => {
+			// Panic: Safe to unwrap because there should be at least one element in the sequence
+			if nv.path.segments.first().unwrap().ident == "default" {
+				match nv.value {
+					syn::Expr::Lit(e) => match e.lit {
+						syn::Lit::Bool(s) => s.value,
+						_ => {
+							return Err(Error::new(
+								item_fn.span(),
+								"Default field on query function options must have a Boolean value",
+							));
+						}
+					},
+					_ => {
+						return Err(Error::new(
+							item_fn.span(),
+							"Default field on query function options must have a Boolean value",
+						));
+					}
+				}
+			} else {
+				return Err(Error::new(
+					item_fn.span(),
+					"Default field must be set if options are included for the query function",
+				));
+			}
+		}
+		Some(Path(p)) => {
+			let seg: &syn::PathSegment = p.segments.first().unwrap();
+			if seg.ident == "default" {
+				match seg.arguments {
+					syn::PathArguments::None => true,
+					_ => return Err(Error::new(item_fn.span(), "Default field in query options path cannot have any parenthized or bracketed arguments")),
+				}
+			} else {
+				return Err(Error::new(
+					item_fn.span(),
+					"Default field must be set if options are included for the query function",
+				));
+			}
+		}
+		None => false,
+		_ => {
+			return Err(Error::new(
+				item_fn.span(),
+				"Cannot parse query function options",
+			));
+		}
+	};
+
+	Ok(QuerySpec {
+		function,
+		default,
+		input_type,
+		output_type,
+	})
+}
+
+#[proc_macro_attribute]
+pub fn query(attr: TokenStream, item: TokenStream) -> TokenStream {
+	let mut to_return = proc_macro2::TokenStream::from(item.clone());
+	let item_fn = parse_macro_input!(item as ItemFn);
+	let opt_meta: Option<Meta> = if attr.is_empty().not() {
+		Some(parse_macro_input!(attr as Meta))
+	} else {
+		None
+	};
+	let spec = match parse_named_query_spec(opt_meta, item_fn) {
+		Ok(span) => span,
+		Err(err) => return err.to_compile_error().into(),
+	};
+
+	let struct_name = Ident::new(
+		spec.function
+			.to_string()
+			.to_case(convert_case::Case::Pascal)
+			.as_str(),
+		Span::call_site(),
+	);
+	let ident = &spec.function;
+	let input_type = spec.input_type;
+	let output_type = spec.output_type;
+
+	let to_follow = quote::quote! {
+		struct #struct_name {}
+
+		#[hipcheck_sdk::prelude::async_trait]
+		impl hipcheck_sdk::prelude::Query for #struct_name {
+			fn input_schema(&self) -> hipcheck_sdk::prelude::JsonSchema {
+				hipcheck_sdk::prelude::schema_for!(#input_type).schema
+			}
+
+			fn output_schema(&self) -> hipcheck_sdk::prelude::JsonSchema {
+				hipcheck_sdk::prelude::schema_for!(#output_type).schema
+			}
+
+			async fn run(&self, engine: &mut hipcheck_sdk::prelude::PluginEngine, input: hipcheck_sdk::prelude::Value) -> hipcheck_sdk::prelude::Result<hipcheck_sdk::prelude::Value> {
+				let input = hipcheck_sdk::prelude::from_value(input).map_err(|_|
+					hipcheck_sdk::prelude::Error::UnexpectedPluginQueryInputFormat)?;
+				let output = #ident(engine, input).await?;
+				hipcheck_sdk::prelude::to_value(output).map_err(|_|
+					hipcheck_sdk::prelude::Error::UnexpectedPluginQueryOutputFormat)
+			}
+		}
+	};
+
+	QUERIES.lock().unwrap().push(NamedQuerySpec {
+		struct_name: struct_name.to_string(),
+		function: spec.function.to_string(),
+		default: spec.default,
+	});
+
+	to_return.extend(to_follow);
+	proc_macro::TokenStream::from(to_return)
+}

plugins/dummy_sha256_sdk/Cargo.toml

@@ -7,6 +7,6 @@ publish = false
 
 [dependencies]
 clap = { version = "4.5.18", features = ["derive"] }
-hipcheck-sdk = { path = "../../sdk/rust" }
+hipcheck-sdk = { path = "../../sdk/rust", features = ["macros"]}
 sha2 = "0.10.8"
 tokio = { version = "1.40.0", features = ["rt"] }

plugins/dummy_sha256_sdk/src/main.rs

@@ -4,52 +4,17 @@ use clap::Parser;
 use hipcheck_sdk::prelude::*;
 use sha2::{Digest, Sha256};
 
-static SHA256_KEY_SCHEMA: &str = include_str!("../schema/query_schema_sha256.json");
-static SHA256_OUTPUT_SCHEMA: &str = include_str!("../schema/query_schema_sha256.json");
-
-/// calculate sha256 of provided content
-fn sha256(content: &[u8]) -> Vec<u8> {
+#[query(default = false)]
+async fn query_sha256(_engine: &mut PluginEngine, content: Vec<u8>) -> Result<Vec<u8>> {
 	let mut hasher = Sha256::new();
-	hasher.update(content);
-	hasher.finalize().to_vec()
+	hasher.update(content.as_slice());
+	Ok(hasher.finalize().to_vec())
 }
 
 /// This plugin takes in a Value::Array(Vec<Value::Number>) and calculates its sha256
 #[derive(Clone, Debug)]
 struct Sha256Plugin;
 
-#[async_trait]
-impl Query for Sha256Plugin {
-	fn input_schema(&self) -> JsonSchema {
-		from_str(SHA256_KEY_SCHEMA).unwrap()
-	}
-
-	fn output_schema(&self) -> JsonSchema {
-		from_str(SHA256_OUTPUT_SCHEMA).unwrap()
-	}
-
-	async fn run(
-		&self,
-		_engine: &mut PluginEngine,
-		input: Value,
-	) -> hipcheck_sdk::error::Result<Value> {
-		let Value::Array(data) = &input else {
-			return Err(Error::UnexpectedPluginQueryInputFormat);
-		};
-
-		let data = data
-			.iter()
-			.map(|elem| elem.as_u64().map(|num| num as u8))
-			.collect::<Option<Vec<_>>>()
-			.ok_or_else(|| Error::UnexpectedPluginQueryInputFormat)?;
-
-		let hash = sha256(&data);
-		// convert to Value
-		let hash = hash.iter().map(|x| Value::Number((*x).into())).collect();
-		Ok(hash)
-	}
-}
-
 impl Plugin for Sha256Plugin {
 	const PUBLISHER: &'static str = "dummy";
 
@@ -70,7 +35,7 @@ impl Plugin for Sha256Plugin {
 	fn queries(&self) -> impl Iterator<Item = NamedQuery> {
 		vec![NamedQuery {
 			name: "sha256",
-			inner: Box::new(Sha256Plugin),
+			inner: Box::new(QuerySha256 {}),
 		}]
 		.into_iter()
 	}

sdk/rust/Cargo.toml

@@ -15,7 +15,11 @@ tokio = { version = "1.39.2", features = ["rt"] }
 tokio-stream = "0.1.15"
 tonic = "0.12.1"
 schemars = "0.8.21"
+hipcheck-sdk-macros = { path = "../../hipcheck-sdk-macros", version = "0.1.0", optional = true }
 
 [build-dependencies]
 anyhow = "1.0.86"
 tonic-build = "0.12.1"
+
+[features]
+macros = ["hipcheck-sdk-macros"]

sdk/rust/src/error.rs

@@ -49,6 +49,10 @@ pub enum Error {
 	#[error("unexpected JSON value from plugin")]
 	UnexpectedPluginQueryInputFormat,
 
+	/// The `Query::run` function implementation produced an output that cannot be serialized to JSON
+	#[error("plugin output could not be serialized to JSON")]
+	UnexpectedPluginQueryOutputFormat,
+
 	/// The `PluginEngine` received a request for an unknown query endpoint
 	#[error("could not determine which plugin query to run")]
 	UnknownPluginQuery,