feat: improve RpcPeer connection handling, + RpcLimits, add WebSocket…

…Channel.MaxItemSize, improve RpcPeerStateMonitor, etc.

samples/TodoApp/UI/Pages/TodoPage.razor

@@ -19,6 +19,7 @@
 
 <h1>Todo List</h1>
 
+<TextConnectionStatus />
 <StateOfStateBadge State="@State" />
 <Div Margin="Margin.Is1.OnY">
     Updated: <b><MomentsAgoBadge Value="LastStateUpdateTime" /></b>

samples/TodoApp/UI/Shared/BarConnectionStatus.razor

@@ -1,22 +1,15 @@
 @using Stl.Rpc
-@inherits ComputedStateComponent<RpcPeerState?>
-@inject RpcClientPeerReconnectDelayer RpcClientPeerReconnectDelayer
+@inherits StatefulComponentBase<IState<RpcPeerComputedState>>
 
 @{
-    var m = State.ValueOrDefault ?? new RpcPeerState(true);
-    var isReconnecting = !m.IsConnected
-        && m.ReconnectsAt <= RpcClientPeerReconnectDelayer.Clock.Now;
-    var message = m.IsConnected
-        ? "Connected."
-        : m.Error?.Message.Trim() ?? "Unknown error.";
-    if (!message.EndsWith(".") && !message.EndsWith("!") && !message.EndsWith("?"))
-        message += ".";
-    var iconName = m.IsConnected == false
-        ? FontAwesomeIcons.ExclamationTriangle
-        : FontAwesomeIcons.Cloud;
-    var textColor = m.IsConnected == false
-        ? TextColor.Warning
-        : TextColor.Default;
+    var m = State.Value;
+    var isConnected = m.IsOrLikelyConnected;
+    var iconName = isConnected
+        ? FontAwesomeIcons.Cloud
+        : FontAwesomeIcons.ExclamationTriangle;
+    var textColor = isConnected
+        ? TextColor.Default
+        : TextColor.Warning;
 }
 
 <BarItem>
@@ -26,42 +19,25 @@
         </BarDropdownToggle>
         <BarDropdownMenu>
             <BarDropdownItem TextColor="@textColor">
-                <span>@message</span>
-                @if (!m.IsConnected) {
-                    if (isReconnecting) {
-                        <span> Reconnecting... </span>
-                    }
-                    else {
-                        <span> Will reconnect <TimerBadge ExpiresAt="m.ReconnectsAt"/>. </span>
-                        <Button Color="Color.Success" Clicked="@TryReconnect">Reconnect</Button>
-                    }
+                <span>@m.GetActivityDescription(true)</span>
+                @if (m.ReconnectsIn is { } reconnectsIn) {
+                    <span> Will reconnect <TimerBadge ExpiresAt="@(Clock.Now + reconnectsIn)"/>. </span>
+                    <Button Color="Color.Success" Clicked="@Reconnect">Reconnect</Button>
                 }
             </BarDropdownItem>
         </BarDropdownMenu>
     </BarDropdown>
 </BarItem>
 
 @code {
-    private RpcPeerStateMonitor? _monitor;
+    [Inject] private RpcPeerStateMonitor Monitor { get; init; } = null!;
+    [Inject] private IMomentClock Clock { get; init; } = null!;
 
-    [Parameter]
-    public string CssClass { get; set; } = "";
+    [Parameter] public string CssClass { get; set; } = "";
 
-    protected override void OnInitialized()
-    {
-        _monitor = Services.GetService<RpcPeerStateMonitor>();
-        _monitor?.Start();
-        base.OnInitialized();
-    }
+    protected override IState<RpcPeerComputedState> CreateState()
+        => Monitor.ComputedState;
 
-    protected override async Task<RpcPeerState?> ComputeState(CancellationToken cancellationToken)
-    {
-        if (_monitor == null)
-            return null;
-
-        return await _monitor.State.Use(cancellationToken).ConfigureAwait(false);
-    }
-
-    private void TryReconnect()
+    private void Reconnect()
         => Services.RpcHub().InternalServices.ClientPeerReconnectDelayer.CancelDelays();
 }

samples/TodoApp/UI/Shared/TextConnectionStatus.razor

@@ -0,0 +1,32 @@
+@using Stl.Rpc
+@inherits StatefulComponentBase<IState<RpcPeerComputedState>>
+
+@{
+    var m = State.Value;
+    var isConnected = m.IsOrLikelyConnected;
+}
+
+<Div Margin="Margin.Is1.OnY" TextColor="@(isConnected ? TextColor.Default : TextColor.Warning)">
+    <span>Connection state: </span>
+    <strong>
+        <span>@(m.GetActivityDescription(true))</span>
+        @if (m.ReconnectsIn is { } reconnectsIn) {
+            <span> Will reconnect <TimerBadge ExpiresAt="@(Clock.Now + reconnectsIn)"/>. </span>
+            <Anchor TextColor="@TextColor.Success" Clicked="@Reconnect">Reconnect</Anchor>
+        }
+    </strong>
+</Div>
+
+@code {
+    [Inject] private RpcPeerStateMonitor Monitor { get; init; } = null!;
+    [Inject] private IMomentClock Clock { get; init; } = null!;
+
+    [Parameter]
+    public string CssClass { get; set; } = "";
+
+    protected override IState<RpcPeerComputedState> CreateState()
+        => Monitor.ComputedState;
+
+    private void Reconnect()
+        => Services.RpcHub().InternalServices.ClientPeerReconnectDelayer.CancelDelays();
+}

samples/TodoApp/UI/StartupHelper.cs

@@ -29,7 +29,6 @@ public static void ConfigureServices(IServiceCollection services, WebAssemblyHos
         // Fusion services
         var fusion = services.AddFusion();
         fusion.AddAuthClient();
-        fusion.AddRpcPeerStateMonitor();
         fusion.AddBlazor().AddAuthentication().AddPresenceReporter();
 
         var rpc = fusion.Rpc;
@@ -71,6 +70,7 @@ public static void ConfigureSharedServices(IServiceCollection services)
         fusion.AddComputedGraphPruner(_ => new() { CheckPeriod = TimeSpan.FromSeconds(10) });
         fusion.AddFusionTime();
         fusion.AddService<TodoUI>(ServiceLifetime.Scoped);
+        services.AddScoped(c => new RpcPeerStateMonitor(c, OSInfo.IsAnyClient ? RpcPeerRef.Default : null));
 
         // Default update delay is 0.5s
         services.AddScoped<IUpdateDelayer>(c => new UpdateDelayer(c.UIActionTracker(), 0.5));

src/Stl.Fusion/Extensions/FusionBuilderExt.cs

@@ -1,5 +1,4 @@
 using Stl.Fusion.Extensions.Internal;
-using Stl.Rpc;
 
 namespace Stl.Fusion.Extensions;
 
@@ -14,17 +13,4 @@ public static FusionBuilder AddFusionTime(this FusionBuilder fusion,
             fusion.AddService<IFusionTime, FusionTime>();
         return fusion;
     }
-
-    public static FusionBuilder AddRpcPeerStateMonitor(this FusionBuilder fusion,
-        Func<IServiceProvider, RpcPeerRef>? peerRefResolver = null)
-    {
-        var services = fusion.Services;
-        services.AddSingleton(c => {
-            var monitor = new RpcPeerStateMonitor(c);
-            if (peerRefResolver != null)
-                monitor.PeerRef = peerRefResolver.Invoke(c);
-            return monitor;
-        });
-        return fusion;
-    }
 }

src/Stl.Fusion/Extensions/RpcPeerComputedState.cs

@@ -0,0 +1,41 @@
+namespace Stl.Fusion.Extensions;
+
+public enum RpcPeerComputedStateKind
+{
+    Connected = 0,
+    JustDisconnected,
+    Disconnected,
+    Reconnecting,
+}
+
+public sealed record RpcPeerComputedState(
+    RpcPeerComputedStateKind Kind,
+    Exception? LastError = null,
+    TimeSpan? ReconnectsIn = null)
+{
+    public bool IsConnected => Kind == RpcPeerComputedStateKind.Connected;
+    public bool IsOrLikelyConnected =>
+        Kind == RpcPeerComputedStateKind.Connected
+        || Kind == RpcPeerComputedStateKind.JustDisconnected;
+
+    public string GetActivityDescription(bool useLastError = false)
+    {
+        switch (Kind) {
+        case RpcPeerComputedStateKind.Connected:
+            return "Connected.";
+        case RpcPeerComputedStateKind.JustDisconnected:
+            return "Connected, checking...";
+        case RpcPeerComputedStateKind.Reconnecting:
+            return "Reconnecting...";
+        }
+        if (LastError == null || !useLastError)
+            return "Disconnected.";
+
+        var message = LastError.Message.Trim();
+        if (!(message.EndsWith(".", StringComparison.Ordinal)
+            || message.EndsWith("!", StringComparison.Ordinal)
+            || message.EndsWith("?", StringComparison.Ordinal)))
+            message += ".";
+        return "Disconnected: " + message;
+    }
+}

src/Stl.Fusion/Extensions/RpcPeerState.cs

@@ -1,6 +1,42 @@
+using Stl.Rpc.Infrastructure;
+
 namespace Stl.Fusion.Extensions;
 
-public record RpcPeerState(
-    bool IsConnected,
-    Exception? Error = null,
-    Moment ReconnectsAt = default); // Relative to CpuClock.Now
+// Any Moment below is derived with RpcHub.Clock, which is CpuClock
+
+public abstract record RpcPeerState
+{
+    public abstract Moment EnteredAt { get; }
+
+    public RpcPeerConnectedState ToConnected(Moment now)
+        => this as RpcPeerConnectedState ?? new RpcPeerConnectedState(now);
+
+    public RpcPeerDisconnectedState ToDisconnected(Moment now, Moment reconnectsAt, RpcPeerConnectionState state)
+        => ToDisconnected(now, reconnectsAt, state.Error);
+    public RpcPeerDisconnectedState ToDisconnected(Moment now, Moment reconnectsAt, Exception? lastError)
+    {
+        if (this is not RpcPeerDisconnectedState d)
+            return new RpcPeerDisconnectedState(now, reconnectsAt, lastError);
+
+        if (reconnectsAt == d.ReconnectsAt && d.LastError == lastError)
+            return d;
+
+        return new RpcPeerDisconnectedState(d.DisconnectedAt, reconnectsAt, lastError ?? d.LastError);
+    }
+}
+
+public sealed record RpcPeerConnectedState(
+    Moment ConnectedAt
+) : RpcPeerState
+{
+    public override Moment EnteredAt => ConnectedAt;
+}
+
+public sealed record RpcPeerDisconnectedState(
+    Moment DisconnectedAt,
+    Moment ReconnectsAt, // < Now = tries to reconnect now
+    Exception? LastError
+) : RpcPeerState
+{
+    public override Moment EnteredAt => DisconnectedAt;
+}