Unify the methods to save and load session keys

example/index.ts

@@ -3,10 +3,10 @@ import {getRandomBytesSync} from "ethereum-cryptography/random";
 
 async function example(): Promise<void> {
     const openfort = new Openfort("pk_test_a6508438-48d2-4af9-a557-51b638800a14", "http://localhost:3002");
-    if (!(await openfort.loadSessionKeyFromFile())) {
+    if (!(await openfort.loadSessionKey())) {
         openfort.createSessionKey();
         // TODO: call server to authenticate user and register session
-        await openfort.saveSessionKeyToFile();
+        await openfort.saveSessionKey();
     }
 
     // TODO: replace the message

src/key-pair.ts

@@ -8,8 +8,7 @@ import {arrayify, Bytes, BytesLike, joinSignature} from "@ethersproject/bytes";
 import {hashMessage} from "@ethersproject/hash";
 
 export class KeyPair extends SigningKey {
-    private static readonly localStorage = new LocalStorage();
-    private static readonly fileStorage = new FileStorage();
+    private static readonly storage = LocalStorage.isAvailable ? new LocalStorage() : new FileStorage();
 
     /**
      * Initialize keypair based on the private key, if it is provided or generate a brand new keypair.
@@ -28,47 +27,17 @@ export class KeyPair extends SigningKey {
     }
 
     /**
-     * Save to the storage provided in the parameter of the function
-     * @param storage The implementation of BaseStorage interface to store and load
+     * Save to the storage initialized as a static property of the KeyPair class
      */
-    public async saveToStorage(storage: BaseStorage): Promise<void> {
-        await storage.save(StorageKeys.SESSION_KEY, this.privateKey);
+    public async save(): Promise<void> {
+        await KeyPair.storage.save(StorageKeys.SESSION_KEY, this.privateKey);
     }
 
     /**
-     * Save the generated key to the local storage
+     * Load private key from the storage and generate keypair based on it.
      */
-    public async saveToLocalStorage(): Promise<void> {
-        await this.saveToStorage(KeyPair.localStorage);
-    }
-
-    /**
-     * Save the generated key to the json file in the local file system
-     */
-    public async saveToFile(): Promise<void> {
-        await this.saveToStorage(KeyPair.fileStorage);
-    }
-
-    /**
-     * Load private key from the json file in the local file system and generate keypair based on it.
-     * @param storage The implementation of BaseStorage interface to store and load
-     */
-    public static async loadFromStorage(storage: BaseStorage): Promise<KeyPair | null> {
-        const privateKey = await storage.get(StorageKeys.SESSION_KEY);
+    public static async load(): Promise<KeyPair | null> {
+        const privateKey = await KeyPair.storage.get(StorageKeys.SESSION_KEY);
         return privateKey ? new KeyPair(arrayify(privateKey)) : null;
     }
-
-    /**
-     * Load private key from the local storage and generate keypair based on it.
-     */
-    public static async loadFromLocalStorage(): Promise<KeyPair | null> {
-        return KeyPair.loadFromStorage(KeyPair.localStorage);
-    }
-
-    /**
-     * Load private key from the json file in the local file system and generate keypair based on it.
-     */
-    public static async loadFromFile(): Promise<KeyPair | null> {
-        return KeyPair.loadFromStorage(KeyPair.fileStorage);
-    }
 }

src/openfort.ts

@@ -40,22 +40,13 @@ export default class Openfort {
         return this._keyPair;
     }
 
-    public async loadSessionKeyFromFile(): Promise<KeyPair | null> {
-        this._keyPair = await KeyPair.loadFromFile();
+    public async loadSessionKey(): Promise<KeyPair | null> {
+        this._keyPair = await KeyPair.load();
         return this._keyPair;
     }
 
-    public async loadSessionKeyFromLocalStorage(): Promise<KeyPair | null> {
-        this._keyPair = await KeyPair.loadFromLocalStorage();
-        return this._keyPair;
-    }
-
-    public async saveSessionKeyToFile(): Promise<void> {
-        return this.keyPair.saveToFile();
-    }
-
-    public async saveSessionKeyToLocalStorage(): Promise<void> {
-        return this.keyPair.saveToLocalStorage();
+    public async saveSessionKey(): Promise<void> {
+        return this.keyPair.save();
     }
 
     public signMessage(message: Bytes | string): string {

src/storage/local-storage.ts

@@ -7,12 +7,16 @@ export class LocalStorage implements BaseStorage {
 
     public constructor(private readonly name?: string) {}
 
+    public static get isAvailable(): boolean {
+        return "localStorage" in global && !!global.localStorage;
+    }
+
     private formatKey(key: StorageKeys): string {
         return [LocalStorage._prefix, this.name, key].filter((n) => n).join(LocalStorage._separator);
     }
 
     private static get localStorage(): LocalStorageInterface {
-        if ("localStorage" in global && global.localStorage) {
+        if (LocalStorage.isAvailable) {
             return global.localStorage as LocalStorageInterface;
         }
         throw Error("Local storage is not available in the current context");