fix: Serialization of contract artifact

yarn-project/.gitignore

@@ -43,6 +43,7 @@ scripts/tmp
 noir-contracts.js/src
 noir-contracts.js/artifacts/
 noir-contracts.js/codegenCache.json
+types/fixtures/*.json
 
 .yarn/*
 !.yarn/patches

yarn-project/types/package.json

@@ -13,16 +13,19 @@
     "./noir": "./dest/noir/index.js"
   },
   "scripts": {
-    "build": "yarn clean && tsc -b",
+    "build": "yarn clean && yarn generate && tsc -b",
     "build:dev": "tsc -b --watch",
     "clean": "rm -rf ./dest .tsbuildinfo",
     "formatting": "run -T prettier --check ./src && run -T eslint ./src",
     "formatting:fix": "run -T eslint --fix ./src && run -T prettier -w ./src",
     "test:light": "NODE_NO_WARNINGS=1 node --experimental-vm-modules $(yarn bin jest) --passWithNoTests",
-    "test": "NODE_NO_WARNINGS=1 node --experimental-vm-modules $(yarn bin jest) --passWithNoTests"
+    "test": "NODE_NO_WARNINGS=1 node --experimental-vm-modules $(yarn bin jest) --passWithNoTests",
+    "generate": "yarn generate:noir-contracts",
+    "generate:noir-contracts": "./scripts/copy-contracts.sh"
   },
   "inherits": [
-    "../package.common.json"
+    "../package.common.json",
+    "./package.local.json"
   ],
   "jest": {
     "preset": "ts-jest/presets/default-esm",

yarn-project/types/package.local.json

@@ -0,0 +1,7 @@
+{
+  "scripts": {
+    "build": "yarn clean && yarn generate && tsc -b",
+    "generate": "yarn generate:noir-contracts",
+    "generate:noir-contracts": "./scripts/copy-contracts.sh"
+  }
+}

yarn-project/types/scripts/copy-contracts.sh

@@ -0,0 +1,5 @@
+#! /bin/bash
+set -euo pipefail
+mkdir -p ./fixtures
+
+cp "../../noir-projects/noir-contracts/target/benchmarking_contract-Benchmarking.json" ./fixtures/Benchmarking.test.json

yarn-project/types/src/abi/contract_artifact.test.ts

@@ -0,0 +1,12 @@
+import { getSampleContractArtifact } from '../test/fixtures.js';
+import { contractArtifactFromBuffer, contractArtifactToBuffer } from './contract_artifact.js';
+
+describe('contract_artifact', () => {
+  it('serializes and deserializes an instance', () => {
+    const artifact = getSampleContractArtifact();
+    delete artifact.aztecNrVersion;
+    const serialized = contractArtifactToBuffer(artifact);
+    const deserialized = contractArtifactFromBuffer(serialized);
+    expect(deserialized).toEqual(artifact);
+  });
+});

yarn-project/types/src/abi/contract_artifact.ts

@@ -23,8 +23,21 @@ import { mockVerificationKey } from './mocked_keys.js';
  * @returns A buffer.
  */
 export function contractArtifactToBuffer(artifact: ContractArtifact): Buffer {
-  // TODO(@spalladino): More efficient serialization
-  return Buffer.from(JSON.stringify(artifact), 'utf8');
+  return Buffer.from(
+    JSON.stringify(artifact, (key, value) => {
+      if (
+        key === 'bytecode' &&
+        value !== null &&
+        typeof value === 'object' &&
+        value.type === 'Buffer' &&
+        Array.isArray(value.data)
+      ) {
+        return Buffer.from(value.data).toString('base64');
+      }
+      return value;
+    }),
+    'utf-8',
+  );
 }
 
 /**
@@ -33,8 +46,12 @@ export function contractArtifactToBuffer(artifact: ContractArtifact): Buffer {
  * @returns Deserialized artifact.
  */
 export function contractArtifactFromBuffer(buffer: Buffer): ContractArtifact {
-  // TODO(@spalladino): More efficient serialization
-  return JSON.parse(buffer.toString('utf8')) as ContractArtifact;
+  return JSON.parse(buffer.toString('utf-8'), (key, value) => {
+    if (key === 'bytecode' && typeof value === 'string') {
+      return Buffer.from(value, 'base64');
+    }
+    return value;
+  });
 }
 
 /**

yarn-project/types/src/test/fixtures.ts

@@ -0,0 +1,19 @@
+import { ContractArtifact } from '@aztec/foundation/abi';
+
+import { readFileSync } from 'fs';
+import { dirname, resolve } from 'path';
+import { fileURLToPath } from 'url';
+
+import { loadContractArtifact } from '../abi/contract_artifact.js';
+import { NoirCompiledContract } from '../noir/index.js';
+
+// Copied from the build output for the contract `Benchmarking` in noir-contracts
+export function getSampleContractArtifact(): ContractArtifact {
+  const path = getPathToFixture('Benchmarking.test.json');
+  const content = JSON.parse(readFileSync(path).toString()) as NoirCompiledContract;
+  return loadContractArtifact(content);
+}
+
+function getPathToFixture(name: string) {
+  return resolve(dirname(fileURLToPath(import.meta.url)), `../../fixtures/${name}`);
+}