feat(rln): package rln w/ resources into a static lib (#118)

* feat(rln): package resources into lib

* fix(rln): use Path

* fix(rln): fmt

* fix(rln): trailing slash

.github/workflows/nightly-release.yml

@@ -6,6 +6,13 @@ on:
 
 jobs:
   linux:
+    strategy:
+      matrix:
+        target: 
+          - x86_64-unknown-linux-gnu
+          # TODO: enable after https://github.com/rust-lang/cargo/issues/4133 is resolved
+          # - aarch64-unknown-linux-gnu
+          # - i686-unknown-linux-gnu
     name: Linux build
     runs-on: ubuntu-latest
     steps:
@@ -17,25 +24,32 @@ jobs:
           profile: minimal
           toolchain: stable
           override: true
+          target: ${{ matrix.target }}
       - name: Update git submodules
         run: git submodule update --init --recursive
       - name: cargo build
         run: |
-          cargo build --release --workspace --exclude rln-wasm
+          cargo build --release --target ${{ matrix.target }} --workspace --exclude rln-wasm
           mkdir release
-          cp target/release/librln* release/
-          tar -czvf linux-rln.tar.gz release/
+          cp target/${{ matrix.target }}/release/librln* release/
+          tar -czvf ${{ matrix.target }}-rln.tar.gz release/
 
       - name: Upload archive artifact
         uses: actions/upload-artifact@v2
         with:
-          name: linux-archive
-          path: linux-rln.tar.gz
+          name: ${{ matrix.target }}-archive
+          path: ${{ matrix.target }}-rln.tar.gz
           retention-days: 2
 
   macos:
     name: MacOS build
     runs-on: macos-latest
+    strategy:
+      matrix:
+        target: 
+          - x86_64-apple-darwin
+          # TODO: enable after https://github.com/rust-lang/cargo/issues/4133 is resolved
+          # - aarch64-apple-darwin
     steps:
       - name: Checkout sources
         uses: actions/checkout@v2
@@ -47,20 +61,21 @@ jobs:
           profile: minimal
           toolchain: stable
           override: true
+          target: ${{ matrix.target }}
       - name: Update git submodules
         run: git submodule update --init --recursive
       - name: cargo build
         run: |
-          cargo build --release --workspace --exclude rln-wasm
+          cargo build --release --target ${{ matrix.target }} --workspace --exclude rln-wasm
           mkdir release
-          cp target/release/librln* release/
-          tar -czvf macos-rln.tar.gz release/
+          cp target/${{ matrix.target }}/release/librln* release/
+          tar -czvf ${{ matrix.target }}-rln.tar.gz release/
 
       - name: Upload archive artifact
         uses: actions/upload-artifact@v2
         with:
-          name: macos-archive
-          path: macos-rln.tar.gz
+          name: ${{ matrix.target }}-archive
+          path: ${{ matrix.target }}-rln.tar.gz
           retention-days: 2
 
   browser-rln-wasm:
@@ -125,9 +140,7 @@ jobs:
             --title 'Nightly build ("master" branch)' \
             --generate-notes \
             --notes-start-tag $start_tag \
-            linux-archive/linux-rln.tar.gz \
-            macos-archive/macos-rln.tar.gz \
-            browser-rln-wasm-archive/browser-rln-wasm.tar.gz
+            *-archive/*.tar.gz \
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
 
@@ -136,6 +149,4 @@ jobs:
         with:
           failOnError: false
           name: |
-            linux-archive
-            macos-archive
-            browser-rln-wasm-archive
+            *-archive

rln/Cargo.toml

@@ -5,7 +5,7 @@ edition = "2021"
 license = "MIT OR Apache-2.0"
 
 [lib]
-crate-type = ["cdylib", "rlib", "staticlib"]
+crate-type = ["rlib", "staticlib"]
 
 # This flag disable cargo doctests, i.e. testing example code-snippets in documentation
 doctest = false
@@ -41,7 +41,9 @@ utils = { path = "../utils/", default-features = false }
 pmtree = { git = "https://github.com/Rate-Limiting-Nullifier/pmtree", rev = "f6d1a1fecad72cd39e6808e78085091d541dc882", optional = true}
 
 # serialization
-serde_json = "=1.0.93"
+serde_json = "1.0.48"
+
+include_dir = "=0.7.3"
 
 [dev-dependencies]
 sled = "=0.34.7"

rln/src/circuit.rs

@@ -11,7 +11,6 @@ use cfg_if::cfg_if;
 use color_eyre::{Report, Result};
 use num_bigint::BigUint;
 use serde_json::Value;
-use std::fs::File;
 use std::io::Cursor;
 use std::path::Path;
 use std::str::FromStr;
@@ -22,23 +21,24 @@ cfg_if! {
         use once_cell::sync::OnceCell;
         use std::sync::Mutex;
         use wasmer::{Module, Store};
+        use include_dir::{include_dir, Dir};
     }
 }
 
 const ZKEY_FILENAME: &str = "rln_final.zkey";
-const VK_FILENAME: &str = "verifying_key.json";
+const VK_FILENAME: &str = "verification_key.json";
 const WASM_FILENAME: &str = "rln.wasm";
 
 // These parameters are used for tests
 // Note that the circuit and keys in TEST_RESOURCES_FOLDER are compiled for Merkle trees of height 15, 19 and 20
 // Changing these parameters to other values than these defaults will cause zkSNARK proof verification to fail
 pub const TEST_PARAMETERS_INDEX: usize = 2;
 pub const TEST_TREE_HEIGHT: usize = [15, 19, 20][TEST_PARAMETERS_INDEX];
-pub const TEST_RESOURCES_FOLDER: &str = [
-    "./resources/tree_height_15/",
-    "./resources/tree_height_19/",
-    "./resources/tree_height_20/",
-][TEST_PARAMETERS_INDEX];
+pub const TEST_RESOURCES_FOLDER: &str =
+    ["tree_height_15", "tree_height_19", "tree_height_20"][TEST_PARAMETERS_INDEX];
+
+#[cfg(not(target_arch = "wasm32"))]
+static RESOURCES_DIR: Dir<'_> = include_dir!("$CARGO_MANIFEST_DIR/resources");
 
 // The following types define the pairing friendly elliptic curve, the underlying finite fields and groups default to this module
 // Note that proofs are serialized assuming Fr to be 4x8 = 32 bytes in size. Hence, changing to a curve with different encoding will make proof verification to fail
@@ -63,13 +63,14 @@ pub fn zkey_from_raw(zkey_data: &Vec<u8>) -> Result<(ProvingKey<Curve>, Constrai
 }
 
 // Loads the proving key
+#[cfg(not(target_arch = "wasm32"))]
 pub fn zkey_from_folder(
     resources_folder: &str,
 ) -> Result<(ProvingKey<Curve>, ConstraintMatrices<Fr>)> {
-    let zkey_path = format!("{resources_folder}{ZKEY_FILENAME}");
-    if Path::new(&zkey_path).exists() {
-        let mut file = File::open(&zkey_path)?;
-        let proving_key_and_matrices = read_zkey(&mut file)?;
+    let zkey = RESOURCES_DIR.get_file(Path::new(resources_folder).join(ZKEY_FILENAME));
+    if let Some(zkey) = zkey {
+        let mut c = Cursor::new(zkey.contents());
+        let proving_key_and_matrices = read_zkey(&mut c)?;
         Ok(proving_key_and_matrices)
     } else {
         Err(Report::msg("No proving key found!"))
@@ -93,15 +94,18 @@ pub fn vk_from_raw(vk_data: &Vec<u8>, zkey_data: &Vec<u8>) -> Result<VerifyingKe
 }
 
 // Loads the verification key
+#[cfg(not(target_arch = "wasm32"))]
 pub fn vk_from_folder(resources_folder: &str) -> Result<VerifyingKey<Curve>> {
-    let vk_path = format!("{resources_folder}{VK_FILENAME}");
-    let zkey_path = format!("{resources_folder}{ZKEY_FILENAME}");
+    let vk = RESOURCES_DIR.get_file(Path::new(resources_folder).join(VK_FILENAME));
+    let zkey = RESOURCES_DIR.get_file(Path::new(resources_folder).join(ZKEY_FILENAME));
 
     let verifying_key: VerifyingKey<Curve>;
-
-    if Path::new(&vk_path).exists() {
-        vk_from_json(&vk_path)
-    } else if Path::new(&zkey_path).exists() {
+    if let Some(vk) = vk {
+        verifying_key = vk_from_json(vk.contents_utf8().ok_or(Report::msg(
+            "Could not read verification key from JSON file!",
+        ))?)?;
+        Ok(verifying_key)
+    } else if let Some(_zkey) = zkey {
         let (proving_key, _matrices) = zkey_from_folder(resources_folder)?;
         verifying_key = proving_key.vk;
         Ok(verifying_key)
@@ -128,9 +132,14 @@ pub fn circom_from_raw(wasm_buffer: Vec<u8>) -> Result<&'static Mutex<WitnessCal
 #[cfg(not(target_arch = "wasm32"))]
 pub fn circom_from_folder(resources_folder: &str) -> Result<&'static Mutex<WitnessCalculator>> {
     // We read the wasm file
-    let wasm_path = format!("{resources_folder}{WASM_FILENAME}");
-    let wasm_buffer = std::fs::read(wasm_path)?;
-    circom_from_raw(wasm_buffer)
+    let wasm = RESOURCES_DIR.get_file(Path::new(resources_folder).join(WASM_FILENAME));
+
+    if let Some(wasm) = wasm {
+        let wasm_buffer = wasm.contents();
+        circom_from_raw(wasm_buffer.to_vec())
+    } else {
+        Err(Report::msg("No wasm file found!"))
+    }
 }
 
 // The following function implementations are taken/adapted from https://github.com/gakonst/ark-circom/blob/1732e15d6313fe176b0b1abb858ac9e095d0dbd7/src/zkey.rs
@@ -231,10 +240,8 @@ fn to_verifying_key(json: serde_json::Value) -> Result<VerifyingKey<Curve>> {
 }
 
 // Computes the verification key from its JSON serialization
-fn vk_from_json(vk_path: &str) -> Result<VerifyingKey<Curve>> {
-    let json = std::fs::read_to_string(vk_path)?;
-    let json: Value = serde_json::from_str(&json)?;
-
+fn vk_from_json(vk: &str) -> Result<VerifyingKey<Curve>> {
+    let json: Value = serde_json::from_str(vk)?;
     to_verifying_key(json)
 }
 
@@ -247,6 +254,7 @@ fn vk_from_vector(vk: &[u8]) -> Result<VerifyingKey<Curve>> {
 }
 
 // Checks verification key to be correct with respect to proving key
+#[cfg(not(target_arch = "wasm32"))]
 pub fn check_vk_from_zkey(
     resources_folder: &str,
     verifying_key: VerifyingKey<Curve>,

rln/src/public.rs

@@ -61,7 +61,7 @@ impl RLN<'_> {
     /// use std::io::Cursor;
     ///
     /// let tree_height = 20;
-    /// let resources = Cursor::new("./resources/tree_height_20/");
+    /// let resources = Cursor::new("tree_height_20");
     ///
     /// // We create a new RLN instance
     /// let mut rln = RLN::new(tree_height, resources);