Fix unsubscribe bug found by testing against Bitcraft

Warning message fix (thanks Jeff)

Update for new Subscribe/UnsubscribeMulti

thanks zeke

Add MultiDictionary; update dispatching logic still wrong

Add even more wacky data structures

WHOOOOOO

Fix MultiDictionary bug

More asserts and comments

Tests passing

Better errors, purge dead package

Test

Update for blackholio

Update blackholio

Fix comment

Remove dead

One more dead

COMMENT

More comments

Added a multiplicity test example

Creates a small sample program with a Rust server and C# client that tests various subscriptions and outputs the results to the CLI.

Make sure we insert before we delete

Fix more comments

Add CRDT test for MultiDictionaryDelta

Revert "Added a multiplicity test example"

This reverts commit ff10925.

Undo DLL changes

Author: kazimuth

examples~/quickstart/client/Program.cs

@@ -94,6 +94,7 @@ void PrintMessage(RemoteTables tables, Message message)
 
 void Message_OnInsert(EventContext ctx, Message insertedValue)
 {
+
     if (ctx.Event is not Event<Reducer>.SubscribeApplied)
     {
         PrintMessage(ctx.Db, insertedValue);
@@ -123,25 +124,15 @@ void OnConnect(DbConnection conn, Identity identity, string authToken)
     local_identity = identity;
     AuthToken.SaveToken(authToken);
 
-    var subscriptions = 0;
-    Action<SubscriptionEventContext> waitForSubscriptions = (SubscriptionEventContext ctx) =>
-    {
-        // Note: callbacks are always invoked on the main thread, so you don't need to
-        // worry about thread synchronization or anything like that.
-        subscriptions += 1;
-
-        if (subscriptions == 2)
-        {
-            OnSubscriptionApplied(ctx);
-        }
-    };
-
     var userSubscription = conn.SubscriptionBuilder()
-        .OnApplied(waitForSubscriptions)
-        .Subscribe("SELECT * FROM user");
-    var messageSubscription = conn.SubscriptionBuilder()
-        .OnApplied(waitForSubscriptions)
-        .Subscribe("SELECT * FROM message");
+        .OnApplied(OnSubscriptionApplied)
+        .Subscribe(new string[] {
+            "SELECT * FROM user",
+            "SELECT * FROM message",
+            // It is legal to have redundant subscriptions.
+            // However, keep in mind that data will be sent over the wire multiple times,
+            // once for each subscriptions. This can cause slowdowns if you aren't careful.
+            "SELECT * FROM message" });
 
     // You can also use SubscribeToAllTables, but it should be avoided if you have any large tables:
     // conn.SubscriptionBuilder().OnApplied(OnSubscriptionApplied).SubscribeToAllTables();

src/Event.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 using SpacetimeDB.ClientApi;
 
 namespace SpacetimeDB
@@ -89,8 +90,8 @@ Action<ErrorContext, Exception> callback
         }
 
         public SubscriptionHandle<SubscriptionEventContext, ErrorContext> Subscribe(
-            string querySql
-        ) => new(conn, Applied, Error, querySql);
+            string[] querySqls
+        ) => new(conn, Applied, Error, querySqls);
 
         public void SubscribeToAllTables()
         {
@@ -224,14 +225,14 @@ internal SubscriptionHandle(
             IDbConnection conn,
             Action<SubscriptionEventContext>? onApplied,
             Action<ErrorContext, Exception>? onError,
-            string querySql
+            string[] querySqls
         )
         {
             state = new SubscriptionState.Pending(new());
             this.onApplied = onApplied;
             this.onError = onError;
             this.conn = conn;
-            conn.Subscribe(this, querySql);
+            conn.Subscribe(this, querySqls);
         }
 
         /// <summary>
@@ -254,11 +255,16 @@ public void UnsubscribeThen(Action<SubscriptionEventContext>? onEnded)
             {
                 throw new Exception("Cannot unsubscribe from inactive subscription.");
             }
-            if (onEnded != null)
+            if (this.onEnded != null)
             {
                 // TODO: should we just log here instead? Do we try not to throw exceptions on the main thread?
                 throw new Exception("Unsubscribe already called.");
             }
+            if (onEnded == null)
+            {
+                // We need to put something in there to use this as a boolean. Shrug emoji
+                onEnded = (ctx) => { };
+            }
             this.onEnded = onEnded;
         }
     }