From 5abe77f92c8acebb98a0f2ba9b95be24fd93dd54 Mon Sep 17 00:00:00 2001
From: Martin Karkowski <m.karkowski@dozema.local>
Date: Wed, 17 Nov 2021 07:27:02 +0100
Subject: [PATCH] Adding onPublishersChanged, and publishers

---
 lib/pubSub/nopePubSubSystem.ts         | 144 ++++++++++++++-----------
 lib/types/nope/nopePubSub.interface.ts |   7 ++
 2 files changed, 91 insertions(+), 60 deletions(-)

diff --git a/lib/pubSub/nopePubSubSystem.ts b/lib/pubSub/nopePubSubSystem.ts
index 39de393..cdd3b06 100644
--- a/lib/pubSub/nopePubSubSystem.ts
+++ b/lib/pubSub/nopePubSubSystem.ts
@@ -49,6 +49,13 @@ export class PubSubSystemBase<I extends INopeEventEmitter = INopeEventEmitter, O
 
   readonly subscriptions: INopeObservable<string[]>;
 
+  readonly onPublishersChanged: INopeEventEmitter<{
+    added: string[],
+    removed: string[]
+  }>;
+
+  readonly publishers: INopeObservable<string[]>;
+
   protected _comparePatternAndPath: TcomparePatternAndPathFunc;
 
   /**
@@ -106,27 +113,72 @@ export class PubSubSystemBase<I extends INopeEventEmitter = INopeEventEmitter, O
     this.subscriptions = new NopeObservable();
     this.subscriptions.setContent([]);
 
+    this.publishers = new NopeObservable();
+    this.publishers.setContent([]);
+
     this.onIncrementalDataChange = new NopeEventEmitter();
     this.onSubscriptionChanged = new NopeEventEmitter();
+    this.onPublishersChanged = new NopeEventEmitter();
   }
 
-  protected _determineSusbcriptions(): Set<string> {
+  protected _updateEmitters(beforeAdding: {
+    publishers: Set<string>,
+    subscriptions: Set<string>
+  }): void {
+    const afterAdding = this._determineCurrentPublishersAndSubscribers();
+    const diffSubscribers = determineDifference(beforeAdding.subscriptions, afterAdding.subscriptions);
+    const diffPublishers = determineDifference(beforeAdding.subscriptions, afterAdding.subscriptions);
+
+    if (diffSubscribers.removed.size > 0 || diffSubscribers.added.size > 0) {
+      // Update the currently used subscriptions
+      this.subscriptions.setContent(
+        Array.from(afterAdding.subscriptions)
+      );
+      // Now emit, that there is a new subscription.
+      this.onSubscriptionChanged.emit({
+        added: Array.from(diffSubscribers.added),
+        removed: Array.from(diffSubscribers.removed)
+      });
+    }
+    if (diffPublishers.removed.size > 0 || diffPublishers.added.size > 0) {
+      // Update the currently used subscriptions
+      this.publishers.setContent(
+        Array.from(afterAdding.publishers)
+      );
+      // Now emit, that there is a new subscription.
+      this.onPublishersChanged.emit({
+        added: Array.from(diffPublishers.added),
+        removed: Array.from(diffPublishers.removed)
+      });
+    }
+  }
+
+  protected _determineCurrentPublishersAndSubscribers(): {
+    publishers: Set<string>,
+    subscriptions: Set<string>
+  } {
     const subscriptions = new Set<string>();
+    const publishers = new Set<string>();
 
-
-    for (const { subTopic } of this._emitters.values()) {
+    for (const { subTopic, pubTopic } of this._emitters.values()) {
       if (subTopic) {
         subscriptions.add(subTopic);
       }
+      if (pubTopic) {
+        publishers.add(pubTopic);
+      }
     }
 
-    return subscriptions;
+    return {
+      publishers,
+      subscriptions
+    };
   }
 
   public register(emitter: I, options: IPropertyOptions): O {
     if (!this._emitters.has(emitter as unknown as O)) {
 
-      const subscriptionsBeforeAdding = this._determineSusbcriptions();
+      const beforeAdding = this._determineCurrentPublishersAndSubscribers();
 
       let pubTopic: string | false =
         typeof options.topic === "string"
@@ -175,50 +227,38 @@ export class PubSubSystemBase<I extends INopeEventEmitter = INopeEventEmitter, O
         });
       }
 
+      this._updateEmitters(beforeAdding);
+
       // Now, if required, add the Data to the emitter.
-      if (subTopic) {
-
-        const subscriptionsAfterAdding = this._determineSusbcriptions();
-        const diff = determineDifference(subscriptionsBeforeAdding, subscriptionsAfterAdding);
-
-        if (diff.removed.size > 0 || diff.added.size > 0) {
-          this.subscriptions.setContent(Array.from(subscriptionsAfterAdding));
-          this.onSubscriptionChanged.emit({
-            added: Array.from(diff.added),
-            removed: Array.from(diff.removed)
-          });
-        }
-
-        if (this._sendCurrentDataOnSubscription) {
-          if (containsWildcards(subTopic)) {
-            // This is more Complex.
-            this._patternbasedPullData(subTopic, null).map(item => {
-              // We check if the content is null
-              if (item.data !== null) {
-                (emitter as unknown as O).emit(
-                  item.data,
-                  {
-                    sender: this._id,
-                    mode: "direct",
-                    topic: item.path
-                  }
-                );
-              }
-            });
-          } else {
-            const currentContent = this._pullData(subTopic, null);
-            if (currentContent !== null) {
+      if (subTopic && this._sendCurrentDataOnSubscription) {
+        if (containsWildcards(subTopic)) {
+          // This is more Complex.
+          this._patternbasedPullData(subTopic, null).map(item => {
+            // We check if the content is null
+            if (item.data !== null) {
               (emitter as unknown as O).emit(
-                currentContent,
+                item.data,
                 {
                   sender: this._id,
                   mode: "direct",
-                  topic: subTopic
+                  topic: item.path
                 }
               );
             }
-
+          });
+        } else {
+          const currentContent = this._pullData(subTopic, null);
+          if (currentContent !== null) {
+            (emitter as unknown as O).emit(
+              currentContent,
+              {
+                sender: this._id,
+                mode: "direct",
+                topic: subTopic
+              }
+            );
           }
+
         }
       }
 
@@ -231,7 +271,7 @@ export class PubSubSystemBase<I extends INopeEventEmitter = INopeEventEmitter, O
   public updateOptions(emitter: I, options: IPropertyOptions): void {
     if (this._emitters.has(emitter as unknown as O)) {
 
-      const subscriptionsBeforeAdding = this._determineSusbcriptions();
+      const beforeAdding = this._determineCurrentPublishersAndSubscribers();
 
       const pubTopic =
         typeof options.topic === "string"
@@ -249,29 +289,13 @@ export class PubSubSystemBase<I extends INopeEventEmitter = INopeEventEmitter, O
       data.subTopic = subTopic;
       data.pubTopic = pubTopic;
 
-
-
       this._emitters.set(emitter as unknown as O, data);
 
-      if (subTopic) {
-        const subscriptionsAfterAdding = this._determineSusbcriptions();
-        const diff = determineDifference(subscriptionsBeforeAdding, subscriptionsAfterAdding);
-
-        if (diff.removed.size > 0 || diff.added.size > 0) {
-          // Update the currently used subscriptions
-          this.subscriptions.setContent(
-            Array.from(subscriptionsAfterAdding)
-          );
-          // Now emit, that there is a new subscription.
-          this.onSubscriptionChanged.emit({
-            added: Array.from(diff.added),
-            removed: Array.from(diff.removed)
-          });
-        }
-      }
-
       // Update the Matching Rules.
       this.updateMatchting();
+
+      this._updateEmitters(beforeAdding);
+
     } else {
       throw Error("Already registered Emitter!");
     }
diff --git a/lib/types/nope/nopePubSub.interface.ts b/lib/types/nope/nopePubSub.interface.ts
index 5944e6f..deb8dac 100644
--- a/lib/types/nope/nopePubSub.interface.ts
+++ b/lib/types/nope/nopePubSub.interface.ts
@@ -159,6 +159,13 @@ export interface IPubSubSystem<I extends INopeEventEmitter = INopeEventEmitter,
     added: string[],
     removed: string[],
   }>
+
+  readonly publishers: INopeObservable<string[]>;
+
+  readonly onPublishersChanged: INopeEventEmitter<{
+    added: string[],
+    removed: string[],
+  }>
 }
 
 /**