wallet: make labels private, and access to need lock

e.g. labels plugin iterated over wallet.labels on asyncio thread while user could trigger an edit from Qt thread

electrum/commands.py

@@ -723,7 +723,7 @@ class Commands:
             if balance:
                 item += (format_satoshis(sum(wallet.get_addr_balance(addr))),)
             if labels:
-                item += (repr(wallet.labels.get(addr, '')),)
+                item += (repr(wallet.get_label(addr)),)
             out.append(item)
         return out
 

electrum/gui/kivy/uix/dialogs/addresses.py

@@ -240,7 +240,7 @@ class AddressesDialog(Factory.Popup):
         n = 0
         cards = []
         for address in _list:
-            label = wallet.labels.get(address, '')
+            label = wallet.get_label(address)
             balance = sum(wallet.get_addr_balance(address))
             is_used_and_empty = wallet.is_used(address) and balance == 0
             if self.show_used == 1 and (balance or is_used_and_empty):

electrum/gui/kivy/uix/dialogs/tx_dialog.py

@@ -297,7 +297,7 @@ class TxDialog(Factory.Popup):
     def label_dialog(self):
         from .label_dialog import LabelDialog
         key = self.tx.txid()
-        text = self.app.wallet.get_label(key)
+        text = self.app.wallet.get_label_for_txid(key)
         def callback(text):
             self.app.wallet.set_label(key, text)
             self.update()

electrum/gui/qt/address_list.py

@@ -160,7 +160,7 @@ class AddressList(MyTreeView):
         addresses_beyond_gap_limit = self.wallet.get_all_known_addresses_beyond_gap_limit()
         for address in addr_list:
             num = self.wallet.get_address_history_len(address)
-            label = self.wallet.labels.get(address, '')
+            label = self.wallet.get_label(address)
             c, u, x = self.wallet.get_addr_balance(address)
             balance = c + u + x
             is_used_and_empty = self.wallet.is_used(address) and balance == 0

electrum/gui/qt/history_list.py

@@ -237,7 +237,7 @@ class HistoryModel(CustomModel, Logger):
 
     def update_label(self, index):
         tx_item = index.internalPointer().get_data()
-        tx_item['label'] = self.parent.wallet.get_label(get_item_key(tx_item))
+        tx_item['label'] = self.parent.wallet.get_label_for_txid(get_item_key(tx_item))
         topLeft = bottomRight = self.createIndex(index.row(), HistoryColumns.DESCRIPTION)
         self.dataChanged.emit(topLeft, bottomRight, [Qt.DisplayRole])
         self.parent.utxo_list.update()
@@ -633,7 +633,7 @@ class HistoryList(MyTreeView, AcceptFileDragDrop):
 
     def show_transaction(self, tx_item, tx):
         tx_hash = tx_item['txid']
-        label = self.wallet.get_label(tx_hash) or None # prefer 'None' if not defined (force tx dialog to hide Description field if missing)
+        label = self.wallet.get_label_for_txid(tx_hash) or None # prefer 'None' if not defined (force tx dialog to hide Description field if missing)
         self.parent.show_transaction(tx, tx_desc=label)
 
     def add_copy_menu(self, menu, idx):

electrum/gui/qt/main_window.py

@@ -3188,7 +3188,7 @@ class ElectrumWindow(QMainWindow, MessageBoxMixin, Logger):
         if fee is None:
             self.show_error(_("Can't bump fee: unknown fee for original transaction."))
             return
-        tx_label = self.wallet.get_label(txid)
+        tx_label = self.wallet.get_label_for_txid(txid)
         tx_size = tx.estimated_size()
         old_fee_rate = fee / tx_size  # sat/vbyte
         d = WindowModalDialog(self, _('Bump Fee'))

electrum/gui/qt/utxo_list.py

@@ -98,7 +98,7 @@ class UTXOList(MyTreeView):
         name = utxo.prevout.to_str()
         name_short = utxo.prevout.txid.hex()[:16] + '...' + ":%d" % utxo.prevout.out_idx
         self._utxo_dict[name] = utxo
-        label = self.wallet.get_label(utxo.prevout.txid.hex())
+        label = self.wallet.get_label_for_txid(utxo.prevout.txid.hex())
         amount = self.parent.format_amount(utxo.value_sats(), whitespaces=True)
         labels = [name_short, address, label, amount, '%d'%height]
         utxo_item = [QStandardItem(x) for x in labels]
@@ -178,7 +178,7 @@ class UTXOList(MyTreeView):
             # "Details"
             tx = self.wallet.db.get_transaction(txid)
             if tx:
-                label = self.wallet.get_label(txid) or None # Prefer None if empty (None hides the Description: field in the window)
+                label = self.wallet.get_label_for_txid(txid) or None # Prefer None if empty (None hides the Description: field in the window)
                 menu.addAction(_("Details"), lambda: self.parent.show_transaction(tx, tx_desc=label))
             # "Copy ..."
             idx = self.indexAt(position)

electrum/gui/stdio.py

@@ -108,7 +108,7 @@ class ElectrumGui:
             else:
                 time_str = 'unconfirmed'
 
-            label = self.wallet.get_label(hist_item.txid)
+            label = self.wallet.get_label_for_txid(hist_item.txid)
             messages.append(format_str % (time_str, label, format_satoshis(delta, whitespaces=True),
                                           format_satoshis(hist_item.balance, whitespaces=True)))
 
@@ -140,7 +140,7 @@ class ElectrumGui:
         self.print_list(messages, "%19s  %25s "%("Key", "Value"))
 
     def print_addresses(self):
-        messages = map(lambda addr: "%30s    %30s       "%(addr, self.wallet.labels.get(addr,"")), self.wallet.get_addresses())
+        messages = map(lambda addr: "%30s    %30s       "%(addr, self.wallet.get_label(addr)), self.wallet.get_addresses())
         self.print_list(messages, "%19s  %25s "%("Address", "Label"))
 
     def print_order(self):
@@ -209,7 +209,7 @@ class ElectrumGui:
             return
 
         if self.str_description:
-            self.wallet.labels[tx.txid()] = self.str_description
+            self.wallet.set_label(tx.txid(), self.str_description)
 
         print(_("Please wait..."))
         try:

electrum/gui/text.py

@@ -136,7 +136,7 @@ class ElectrumGui:
             else:
                 time_str = 'unconfirmed'
 
-            label = self.wallet.get_label(hist_item.txid)
+            label = self.wallet.get_label_for_txid(hist_item.txid)
             if len(label) > 40:
                 label = label[0:37] + '...'
             self.history.append(format_str % (time_str, label, format_satoshis(hist_item.delta, whitespaces=True),
@@ -177,7 +177,7 @@ class ElectrumGui:
 
     def print_addresses(self):
         fmt = "%-35s  %-30s"
-        messages = map(lambda addr: fmt % (addr, self.wallet.labels.get(addr,"")), self.wallet.get_addresses())
+        messages = map(lambda addr: fmt % (addr, self.wallet.get_label(addr)), self.wallet.get_addresses())
         self.print_list(messages,   fmt % ("Address", "Label"))
 
     def print_edit_line(self, y, label, text, index, size):
@@ -314,7 +314,7 @@ class ElectrumGui:
             elif out == "Edit label":
                 s = self.get_string(6 + self.pos, 18)
                 if s:
-                    self.wallet.labels[key] = s
+                    self.wallet.set_label(key, s)
 
     def run_banner_tab(self, c):
         self.show_message(repr(c))
@@ -379,7 +379,7 @@ class ElectrumGui:
             return
 
         if self.str_description:
-            self.wallet.labels[tx.txid()] = self.str_description
+            self.wallet.set_label(tx.txid(), self.str_description)
 
         self.show_message(_("Please wait..."), getchar=False)
         try:

electrum/lnworker.py

@@ -678,7 +678,7 @@ class LNWallet(LNWorker):
             item = {
                 'channel_id': bh2u(chan.channel_id),
                 'type': 'channel_opening',
-                'label': self.wallet.get_label(funding_txid) or (_('Open channel') + ' ' + chan.get_id_for_log()),
+                'label': self.wallet.get_label_for_txid(funding_txid) or (_('Open channel') + ' ' + chan.get_id_for_log()),
                 'txid': funding_txid,
                 'amount_msat': chan.balance(LOCAL, ctn=0),
                 'direction': 'received',
@@ -693,7 +693,7 @@ class LNWallet(LNWorker):
             item = {
                 'channel_id': bh2u(chan.channel_id),
                 'txid': closing_txid,
-                'label': self.wallet.get_label(closing_txid) or (_('Close channel') + ' ' + chan.get_id_for_log()),
+                'label': self.wallet.get_label_for_txid(closing_txid) or (_('Close channel') + ' ' + chan.get_id_for_log()),
                 'type': 'channel_closure',
                 'amount_msat': -chan.balance_minus_outgoing_htlcs(LOCAL),
                 'direction': 'sent',
@@ -724,7 +724,7 @@ class LNWallet(LNWorker):
                 'amount_msat': 0,
                 #'amount_msat': amount_msat, # must not be added
                 'type': 'swap',
-                'label': self.wallet.get_label(txid) or label,
+                'label': self.wallet.get_label_for_txid(txid) or label,
             }
         return out
 

electrum/plugins/labels/labels.py

@@ -36,18 +36,18 @@ class LabelsPlugin(BasePlugin):
         self.target_host = 'labels.electrum.org'
         self.wallets = {}
 
-    def encode(self, wallet, msg):
+    def encode(self, wallet: 'Abstract_Wallet', msg: str) -> str:
         password, iv, wallet_id = self.wallets[wallet]
         encrypted = aes_encrypt_with_iv(password, iv, msg.encode('utf8'))
         return base64.b64encode(encrypted).decode()
 
-    def decode(self, wallet, message):
+    def decode(self, wallet: 'Abstract_Wallet', message: str) -> str:
         password, iv, wallet_id = self.wallets[wallet]
         decoded = base64.b64decode(message)
         decrypted = aes_decrypt_with_iv(password, iv, decoded)
         return decrypted.decode('utf8')
 
-    def get_nonce(self, wallet):
+    def get_nonce(self, wallet: 'Abstract_Wallet'):
         # nonce is the nonce to be used with the next change
         nonce = wallet.db.get('wallet_nonce')
         if nonce is None:
@@ -55,12 +55,12 @@ class LabelsPlugin(BasePlugin):
             self.set_nonce(wallet, nonce)
         return nonce
 
-    def set_nonce(self, wallet, nonce):
+    def set_nonce(self, wallet: 'Abstract_Wallet', nonce):
         self.logger.info(f"set {wallet.basename()} nonce to {nonce}")
         wallet.db.put("wallet_nonce", nonce)
 
     @hook
-    def set_label(self, wallet, item, label):
+    def set_label(self, wallet: 'Abstract_Wallet', item, label):
         if wallet not in self.wallets:
             return
         if not item:
@@ -99,7 +99,7 @@ class LabelsPlugin(BasePlugin):
                 except Exception as e:
                     raise Exception('Could not decode: ' + await result.text()) from e
 
-    async def push_thread(self, wallet):
+    async def push_thread(self, wallet: 'Abstract_Wallet'):
         wallet_data = self.wallets.get(wallet, None)
         if not wallet_data:
             raise Exception('Wallet {} not loaded'.format(wallet))
@@ -107,7 +107,7 @@ class LabelsPlugin(BasePlugin):
         bundle = {"labels": [],
                   "walletId": wallet_id,
                   "walletNonce": self.get_nonce(wallet)}
-        for key, value in wallet.labels.items():
+        for key, value in wallet.get_all_labels().items():
             try:
                 encoded_key = self.encode(wallet, key)
                 encoded_value = self.encode(wallet, value)
@@ -118,7 +118,7 @@ class LabelsPlugin(BasePlugin):
                                      'externalId': encoded_key})
         await self.do_post("/labels", bundle)
 
-    async def pull_thread(self, wallet, force):
+    async def pull_thread(self, wallet: 'Abstract_Wallet', force: bool):
         wallet_data = self.wallets.get(wallet, None)
         if not wallet_data:
             raise Exception('Wallet {} not loaded'.format(wallet))
@@ -148,8 +148,8 @@ class LabelsPlugin(BasePlugin):
             result[key] = value
 
         for key, value in result.items():
-            if force or not wallet.labels.get(key):
-                wallet.labels[key] = value
+            if force or not wallet.get_label(key):
+                wallet._set_label(key, value)
 
         self.logger.info(f"received {len(response)} labels")
         self.set_nonce(wallet, response["nonce"] + 1)
@@ -160,21 +160,21 @@ class LabelsPlugin(BasePlugin):
 
     @ignore_exceptions
     @log_exceptions
-    async def pull_safe_thread(self, wallet, force):
+    async def pull_safe_thread(self, wallet: 'Abstract_Wallet', force: bool):
         try:
             await self.pull_thread(wallet, force)
         except ErrorConnectingServer as e:
             self.logger.info(repr(e))
 
-    def pull(self, wallet, force):
+    def pull(self, wallet: 'Abstract_Wallet', force: bool):
         if not wallet.network: raise Exception(_('You are offline.'))
         return asyncio.run_coroutine_threadsafe(self.pull_thread(wallet, force), wallet.network.asyncio_loop).result()
 
-    def push(self, wallet):
+    def push(self, wallet: 'Abstract_Wallet'):
         if not wallet.network: raise Exception(_('You are offline.'))
         return asyncio.run_coroutine_threadsafe(self.push_thread(wallet), wallet.network.asyncio_loop).result()
 
-    def start_wallet(self, wallet):
+    def start_wallet(self, wallet: 'Abstract_Wallet'):
         if not wallet.network: return  # 'offline' mode
         nonce = self.get_nonce(wallet)
         self.logger.info(f"wallet {wallet.basename()} nonce is {nonce}")

electrum/wallet.py

@@ -263,7 +263,7 @@ class Abstract_Wallet(AddressSynchronizer, ABC):
         # saved fields
         self.use_change            = db.get('use_change', True)
         self.multiple_change       = db.get('multiple_change', False)
-        self.labels                = db.get_dict('labels')
+        self._labels                = db.get_dict('labels')
         self.frozen_addresses      = set(db.get('frozen_addresses', []))
         self.frozen_coins          = set(db.get('frozen_coins', []))  # set of txid:vout strings
         self.fiat_value            = db.get_dict('fiat_value')
@@ -423,20 +423,28 @@ class Abstract_Wallet(AddressSynchronizer, ABC):
     def is_deterministic(self) -> bool:
         return self.keystore.is_deterministic()
 
+    def _set_label(self, key: str, value: Optional[str]) -> None:
+        with self.lock:
+            if value is None:
+                self._labels.pop(key, None)
+            else:
+                self._labels[key] = value
+
     def set_label(self, name: str, text: str = None) -> bool:
         if not name:
             return False
         changed = False
-        old_text = self.labels.get(name)
-        if text:
-            text = text.replace("\n", " ")
-            if old_text != text:
-                self.labels[name] = text
-                changed = True
-        else:
-            if old_text is not None:
-                self.labels.pop(name)
-                changed = True
+        with self.lock:
+            old_text = self._labels.get(name)
+            if text:
+                text = text.replace("\n", " ")
+                if old_text != text:
+                    self._labels[name] = text
+                    changed = True
+            else:
+                if old_text is not None:
+                    self._labels.pop(name)
+                    changed = True
         if changed:
             run_hook('set_label', self, name, text)
         return changed
@@ -447,7 +455,7 @@ class Abstract_Wallet(AddressSynchronizer, ABC):
             self.set_label(key, value)
 
     def export_labels(self, path):
-        write_json_file(path, self.labels)
+        write_json_file(path, self.get_all_labels())
 
     def set_fiat_value(self, txid, ccy, text, fx, value_sat):
         if not self.db.get_transaction(txid):
@@ -568,7 +576,7 @@ class Abstract_Wallet(AddressSynchronizer, ABC):
                       and bool(tx_we_already_have_in_db))
         if tx.is_complete():
             if tx_we_already_have_in_db:
-                label = self.get_label(tx_hash)
+                label = self.get_label_for_txid(tx_hash)
                 if tx_mined_status.height > 0:
                     if tx_mined_status.conf:
                         status = _("{} confirmations").format(tx_mined_status.conf)
@@ -680,7 +688,7 @@ class Abstract_Wallet(AddressSynchronizer, ABC):
                 'bc_value': Satoshis(hist_item.delta),
                 'bc_balance': Satoshis(hist_item.balance),
                 'date': timestamp_to_datetime(hist_item.tx_mined_status.timestamp),
-                'label': self.get_label(hist_item.txid),
+                'label': self.get_label_for_txid(hist_item.txid),
                 'txpos_in_block': hist_item.tx_mined_status.txpos,
             }
 
@@ -823,7 +831,7 @@ class Abstract_Wallet(AddressSynchronizer, ABC):
         for invoice in self.get_relevant_invoices_for_tx(tx):
             if invoice.message:
                 labels.append(invoice.message)
-        if labels and not self.labels.get(tx_hash, ''):
+        if labels and not self._labels.get(tx_hash, ''):
             self.set_label(tx_hash, "; ".join(labels))
         return bool(labels)
 
@@ -994,19 +1002,28 @@ class Abstract_Wallet(AddressSynchronizer, ABC):
             item['capital_gain'] = Fiat(cg, fx.ccy)
         return item
 
-    def get_label(self, tx_hash: str) -> str:
-        return self.labels.get(tx_hash, '') or self.get_default_label(tx_hash)
+    def get_label(self, key: str) -> str:
+        # key is typically: address / txid / LN-payment-hash-hex
+        return self._labels.get(key) or ''
+
+    def get_label_for_txid(self, tx_hash: str) -> str:
+        return self._labels.get(tx_hash) or self._get_default_label_for_txid(tx_hash)
 
-    def get_default_label(self, tx_hash) -> str:
+    def _get_default_label_for_txid(self, tx_hash: str) -> str:
+        # if no inputs are ismine, concat labels of output addresses
         if not self.db.get_txi_addresses(tx_hash):
             labels = []
             for addr in self.db.get_txo_addresses(tx_hash):
-                label = self.labels.get(addr)
+                label = self._labels.get(addr)
                 if label:
                     labels.append(label)
             return ', '.join(labels)
         return ''
 
+    def get_all_labels(self) -> Dict[str, str]:
+        with self.lock:
+            return copy.copy(self._labels)
+
     def get_tx_status(self, tx_hash, tx_mined_info: TxMinedInfo):
         extra = []
         height = tx_mined_info.height
@@ -1672,7 +1689,7 @@ class Abstract_Wallet(AddressSynchronizer, ABC):
 
     def get_request_URI(self, req: OnchainInvoice) -> str:
         addr = req.get_address()
-        message = self.labels.get(addr, '')
+        message = self.get_label(addr)
         amount = req.amount_sat
         extra_query_params = {}
         if req.time:

electrum/wallet_db.py

@@ -1051,7 +1051,7 @@ class WalletDB(JsonDB):
         self.tx_fees.pop(txid, None)
 
     @locked
-    def get_dict(self, name):
+    def get_dict(self, name) -> dict:
         # Warning: interacts un-intuitively with 'put': certain parts
         # of 'data' will have pointers saved as separate variables.
         if name not in self.data: