network: implement basic "add server as bookmark" functionality

implement backend and expose it to qt gui

electrum/gui/icons/bookmark.svg

@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="iso-8859-1"?>
+<!-- Generator: Adobe Illustrator 19.1.1, SVG Export Plug-In . SVG Version: 6.00 Build 0)  -->
+<svg version="1.1"  xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" x="0px" y="0px"
+	 viewBox="0 0 40 40" style="enable-background:new 0 0 40 40;" xml:space="preserve">
+<g>
+	<polygon style="fill:#F78F8F;" points="20,31.441 8.5,37.191 8.5,2.5 31.5,2.5 31.5,37.191 	"/>
+	<g>
+		<path style="fill:#C74343;" d="M31,3v33.382l-10.553-5.276L20,30.882l-0.447,0.224L9,36.382V3H31 M32,2H8v36l12-6l12,6V2L32,2z"/>
+	</g>
+</g>
+</svg>

electrum/gui/icons/bookmark_add.svg

@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="iso-8859-1"?>
+<!-- Generator: Adobe Illustrator 25.2.3, SVG Export Plug-In . SVG Version: 6.00 Build 0)  -->
+<svg version="1.1" baseProfile="basic" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" x="0px"
+	 y="0px" viewBox="0 0 40 40" xml:space="preserve">
+<g id="Layer_10">
+</g>
+<g id="fluent_1_">
+</g>
+<g id="color">
+</g>
+<g id="office">
+	<path style="fill:#F78F8F;" d="M20,31.441l-11.5,5.75V2.5h23v34.691L20,31.441z"/>
+	<path style="fill:#C74343;" d="M31,3v33.382l-10.553-5.276L20,30.882l-0.447,0.224L9,36.382V3H31 M32,2H8v36l12-6l12,6V2L32,2z"/>
+	<path style="fill:#BAE0BD;" d="M31,26.5c-4.687,0-8.5-3.813-8.5-8.5s3.813-8.5,8.5-8.5s8.5,3.813,8.5,8.5S35.687,26.5,31,26.5z"/>
+	<path style="fill:#5E9C76;" d="M31,10c4.411,0,8,3.589,8,8s-3.589,8-8,8s-8-3.589-8-8S26.589,10,31,10 M31,9c-4.971,0-9,4.029-9,9
+		s4.029,9,9,9s9-4.029,9-9S35.971,9,31,9L31,9z"/>
+	<polygon style="fill:#FFFFFF;" points="32,23 30,23 30,19 26,19 26,17 30,17 30,13 32,13 32,17 36,17 36,19 32,19 	"/>
+</g>
+<g id="ios">
+</g>
+<g id="fluent">
+</g>
+</svg>

electrum/gui/icons/bookmark_remove.svg

@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="iso-8859-1"?>
+<!-- Generator: Adobe Illustrator 25.2.3, SVG Export Plug-In . SVG Version: 6.00 Build 0)  -->
+<svg version="1.1" baseProfile="basic" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" x="0px"
+	 y="0px" viewBox="0 0 40 40" xml:space="preserve">
+<g id="Layer_10">
+</g>
+<g id="fluent_1_">
+</g>
+<g id="color">
+</g>
+<g id="office">
+	<path style="fill:#F78F8F;" d="M20,31.441l-11.5,5.75V2.5h23v34.691L20,31.441z"/>
+	<path style="fill:#C74343;" d="M31,3v33.382l-10.553-5.276L20,30.882l-0.447,0.224L9,36.382V3H31 M32,2H8v36l12-6l12,6V2L32,2z"/>
+	<path style="fill:#FFC49C;" d="M31,26.5c-4.687,0-8.5-3.813-8.5-8.5s3.813-8.5,8.5-8.5s8.5,3.813,8.5,8.5S35.687,26.5,31,26.5z"/>
+	<path style="fill:#A16A4A;" d="M31,10c4.411,0,8,3.589,8,8s-3.589,8-8,8s-8-3.589-8-8S26.589,10,31,10 M31,9c-4.971,0-9,4.029-9,9
+		s4.029,9,9,9s9-4.029,9-9S35.971,9,31,9L31,9z"/>
+	<rect x="26" y="17" style="fill:#FFFFFF;" width="10" height="2"/>
+</g>
+<g id="ios">
+</g>
+<g id="fluent">
+</g>
+</svg>

electrum/gui/qt/network_dialog.py

@@ -123,6 +123,13 @@ class NodesListWidget(QTreeWidget):
                 def do_set_server():
                     self.setServer.emit(str(server))
                 menu.addAction(read_QIcon("chevron-right.png"), _("Use as server"), do_set_server)
+            def set_bookmark(*, add: bool):
+                self.network.set_server_bookmark(server, add=add)
+                self.update()
+            if self.network.is_server_bookmarked(server):
+                menu.addAction(read_QIcon("bookmark_remove.png"), _("Remove from bookmarks"), lambda: set_bookmark(add=False))
+            else:
+                menu.addAction(read_QIcon("bookmark_add.png"), _("Bookmark this server"), lambda: set_bookmark(add=True))
         elif item_type == self.ItemType.CHAIN:
             chain_id = item.data(0, self.CHAIN_ID_ROLE)
             def do_follow_chain():
@@ -174,6 +181,8 @@ class NodesListWidget(QTreeWidget):
                 item.setToolTip(0, str(i.server))
                 if i == network.interface:
                     item.setIcon(0, read_QIcon("chevron-right.png"))
+                elif network.is_server_bookmarked(i.server):
+                    item.setIcon(0, read_QIcon("bookmark.png"))
                 x.addChild(item)
             if n_chains > 1:
                 connected_servers_item.addChild(x)
@@ -195,6 +204,8 @@ class NodesListWidget(QTreeWidget):
             item = QTreeWidgetItem([server.net_addr_str(), ""])
             item.setData(0, self.ITEMTYPE_ROLE, self.ItemType.DISCONNECTED_SERVER)
             item.setData(0, self.SERVER_ADDR_ROLE, server)
+            if network.is_server_bookmarked(server):
+                item.setIcon(0, read_QIcon("bookmark.png"))
             disconnected_servers_item.addChild(item)
 
         self.addTopLevelItem(connected_servers_item)

electrum/network.py

@@ -581,6 +581,18 @@ class Network(Logger, NetworkRetryManager[ServerAddr]):
                 out[server.host].update({server.protocol: port})
             else:
                 out[server.host] = {server.protocol: port}
+        # add bookmarks
+        bookmarks = self.config.NETWORK_BOOKMARKED_SERVERS or []
+        for server_str in bookmarks:
+            try:
+                server = ServerAddr.from_str(server_str)
+            except ValueError:
+                continue
+            port = str(server.port)
+            if server.host in out:
+                out[server.host].update({server.protocol: port})
+            else:
+                out[server.host] = {server.protocol: port}
         # potentially filter out some
         if self.config.NETWORK_NOONION:
             out = filter_noonion(out)
@@ -706,6 +718,22 @@ class Network(Logger, NetworkRetryManager[ServerAddr]):
         self.oneserver = oneserver
         self.num_server = NUM_TARGET_CONNECTED_SERVERS if not oneserver else 0
 
+    def is_server_bookmarked(self, server: ServerAddr) -> bool:
+        bookmarks = self.config.NETWORK_BOOKMARKED_SERVERS or []
+        return str(server) in bookmarks
+
+    def set_server_bookmark(self, server: ServerAddr, *, add: bool) -> None:
+        server_str = str(server)
+        with self.config.lock:
+            bookmarks = self.config.NETWORK_BOOKMARKED_SERVERS or []
+            if add:
+                if server_str not in bookmarks:
+                    bookmarks.append(server_str)
+            else:  # remove
+                if server_str in bookmarks:
+                    bookmarks.remove(server_str)
+            self.config.NETWORK_BOOKMARKED_SERVERS = bookmarks
+
     async def _switch_to_random_interface(self):
         '''Switch to a random connected server other than the current one'''
         servers = self.get_interfaces()    # Those in connected state

electrum/simple_config.py

@@ -934,6 +934,7 @@ class SimpleConfig(Logger):
     NETWORK_SERVERFINGERPRINT = ConfigVar('serverfingerprint', default=None, type_=str)
     NETWORK_MAX_INCOMING_MSG_SIZE = ConfigVar('network_max_incoming_msg_size', default=1_000_000, type_=int)  # in bytes
     NETWORK_TIMEOUT = ConfigVar('network_timeout', default=None, type_=int)
+    NETWORK_BOOKMARKED_SERVERS = ConfigVar('network_bookmarked_servers', default=None)
 
     WALLET_BATCH_RBF = ConfigVar(
         'batch_rbf', default=False, type_=bool,