Use startup_time from system.connected (#300)

* Handle startup time

* Remove dead code

* Bump protocol version + FE changes

frontend/src/Connection.ts

@@ -204,7 +204,7 @@ export class Connection {
             nodeHardware,
             blockDetails,
             location,
-            connectedAt,
+            startupTime,
           ] = message.payload;
           const pinned = this.pins.has(nodeDetails[0]);
           const node = new Node(
@@ -216,7 +216,7 @@ export class Connection {
             nodeHardware,
             blockDetails,
             location,
-            connectedAt
+            startupTime
           );
 
           nodes.add(node);

frontend/src/common/feed.ts

@@ -80,7 +80,7 @@ export namespace Variants {
       NodeHardware,
       BlockDetails,
       Maybe<NodeLocation>,
-      Timestamp
+      Maybe<Timestamp>
     ];
   }
 

frontend/src/common/index.ts

@@ -9,4 +9,4 @@ import * as FeedMessage from './feed';
 export { Types, FeedMessage };
 
 // Increment this if breaking changes were made to types in `feed.ts`
-export const VERSION: Types.FeedVersion = 30 as Types.FeedVersion;
+export const VERSION: Types.FeedVersion = 31 as Types.FeedVersion;

frontend/src/components/List/Column/UptimeColumn.tsx

@@ -9,7 +9,7 @@ export class UptimeColumn extends React.Component<Column.Props, {}> {
   public static readonly icon = icon;
   public static readonly width = 58;
   public static readonly setting = 'uptime';
-  public static readonly sortBy = ({ connectedAt }: Node) => connectedAt || 0;
+  public static readonly sortBy = ({ startupTime }: Node) => startupTime || 0;
 
   public shouldComponentUpdate(nextProps: Column.Props) {
     // Uptime only changes when the node does
@@ -17,11 +17,15 @@ export class UptimeColumn extends React.Component<Column.Props, {}> {
   }
 
   render() {
-    const { connectedAt } = this.props.node;
+    const { startupTime } = this.props.node;
+
+    if (!startupTime) {
+      return <td className="Column">-</td>;
+    }
 
     return (
       <td className="Column">
-        <Ago when={connectedAt} justTime={true} />
+        <Ago when={startupTime} justTime={true} />
       </td>
     );
   }

frontend/src/state.ts

@@ -43,7 +43,7 @@ export class Node {
   public readonly version: Types.NodeVersion;
   public readonly validator: Maybe<Types.Address>;
   public readonly networkId: Maybe<Types.NetworkId>;
-  public readonly connectedAt: Types.Timestamp;
+  public readonly startupTime: Maybe<Types.Timestamp>;
 
   public readonly sortableName: string;
   public readonly sortableVersion: number;
@@ -82,7 +82,7 @@ export class Node {
     nodeHardware: Types.NodeHardware,
     blockDetails: Types.BlockDetails,
     location: Maybe<Types.NodeLocation>,
-    connectedAt: Types.Timestamp
+    startupTime: Maybe<Types.Timestamp>
   ) {
     const [name, implementation, version, validator, networkId] = nodeDetails;
 
@@ -94,7 +94,7 @@ export class Node {
     this.version = version;
     this.validator = validator;
     this.networkId = networkId;
-    this.connectedAt = connectedAt;
+    this.startupTime = startupTime;
 
     const [major = 0, minor = 0, patch = 0] = (version || '0.0.0')
       .split('.')