Add support for encrypted wallet (#20)

Signed-off-by: cyc60 <avsysoev60@gmail.com>

src/common/accounts.py

@@ -1,5 +1,37 @@
+import json
+import os.path
+
 from eth_account import Account
+from eth_account.account import LocalAccount
+
+from src.config.settings import (
+    WALLET_KEYSTORE_PASSWORD_PATH,
+    WALLET_KEYSTORE_PATH,
+    WALLET_PRIVATE_KEY,
+)
+
+
+def get_operator_account() -> LocalAccount:
+    if WALLET_PRIVATE_KEY:
+        return Account().from_key(WALLET_PRIVATE_KEY)
+
+    if WALLET_KEYSTORE_PATH and WALLET_KEYSTORE_PASSWORD_PATH:
+        if not os.path.isfile(WALLET_KEYSTORE_PATH):
+            raise ValueError(f"Can't open WALLET_KEYSTORE_PATH file. "
+                             f' Path: {WALLET_KEYSTORE_PATH}')
+        if not os.path.isfile(WALLET_KEYSTORE_PASSWORD_PATH):
+            raise ValueError(f"Can't open WALLET_KEYSTORE_PASSWORD_PATH file. "
+                             f'Path: {WALLET_KEYSTORE_PASSWORD_PATH}')
+
+        with open(WALLET_KEYSTORE_PATH, 'r', encoding='utf-8') as f:
+            keyfile_json = json.load(f)
+        with open(WALLET_KEYSTORE_PASSWORD_PATH, 'r', encoding='utf-8') as f:
+            password = f.read().strip()
+        key = Account().decrypt(keyfile_json, password)
+        return Account().from_key(key)
+
+    raise ValueError('Provide WALLET_PRIVATE_KEY setting or combination of '
+                     'WALLET_KEYSTORE_PATH and WALLET_KEYSTORE_PASSWORD_PATH settings')
 
-from src.config.settings import OPERATOR_PRIVATE_KEY
 
-operator_account = Account().from_key(OPERATOR_PRIVATE_KEY)
+operator_account = get_operator_account()

src/config/settings.py

@@ -21,8 +21,10 @@
 # deposit data
 DEPOSIT_DATA_PATH = config('DEPOSIT_DATA_PATH')
 
-# operator
-OPERATOR_PRIVATE_KEY = config('OPERATOR_PRIVATE_KEY')
+# wallet private key
+WALLET_PRIVATE_KEY = config('WALLET_PRIVATE_KEY', default=None)
+WALLET_KEYSTORE_PATH = config('WALLET_KEYSTORE_PATH', default=None)
+WALLET_KEYSTORE_PASSWORD_PATH = config('WALLET_KEYSTORE_PASSWORD_PATH', default=None)
 
 # remote IPFS
 IPFS_FETCH_ENDPOINTS = config(