fix: add missing overloaded load method for cluster keys

src/nilql.ts

@@ -430,6 +430,16 @@ class ClusterKey extends SecretKey {
 
     return clusterKey as ClusterKey;
   }
+
+  /**
+   * Create an instance from its JSON-compatible object representation.
+   */
+  public static load(object: object): ClusterKey {
+    const secretKey = SecretKey.load(object);
+    const clusterKey = new ClusterKey(secretKey.cluster, secretKey.operations);
+    clusterKey.material = secretKey.material;
+    return clusterKey;
+  }
 }
 
 /**

tests/nilql.test.ts

@@ -138,7 +138,7 @@ describe("methods of cryptographic key classes", () => {
     expect(decrypted).toEqual(plaintext);
   });
 
-  test("generate, dump, JSONify, and load key for sum operation with multiple nodes", async () => {
+  test("generate, dump, JSONify, and load secret key for sum operation with multiple nodes", async () => {
     const cluster = { nodes: [{}, {}, {}] };
     const secretKey = await nilql.SecretKey.generate(cluster, { sum: true });
 
@@ -151,6 +151,20 @@ describe("methods of cryptographic key classes", () => {
     expect(decrypted).toEqual(plaintext);
   });
 
+  test("generate, dump, JSONify, and load cluster key for sum operation with multiple nodes", async () => {
+    const cluster = { nodes: [{}, {}, {}] };
+    const clusterKey = await nilql.ClusterKey.generate(cluster, { sum: true });
+
+    const clusterKeyObject = JSON.parse(JSON.stringify(clusterKey.dump()));
+    const clusterKeyLoaded = nilql.ClusterKey.load(clusterKeyObject);
+    expect(clusterKeyLoaded instanceof nilql.ClusterKey).toEqual(true);
+
+    const plaintext = BigInt(123);
+    const ciphertext = await nilql.encrypt(clusterKey, plaintext);
+    const decrypted = await nilql.decrypt(clusterKeyLoaded, ciphertext);
+    expect(decrypted).toEqual(plaintext);
+  });
+
   test("generate key from seed for store operation with single node", async () => {
     const secretKeyFromSeed = await nilql.SecretKey.generate(
       { nodes: [{}] },