Support channel from Publication (can differ in case of wildcard subscriptions)

src/centrifuge.ts

@@ -1699,8 +1699,12 @@ export class Centrifuge extends (EventEmitter as new () => TypedEventEmitter<Cli
   private _getPublicationContext(channel: string, pub: any) {
     const ctx: any = {
       channel: channel,
-      data: pub.data
+      data: pub.data,
+      publicationChannel: channel
     };
+    if (pub.channel) {
+      ctx.publicationChannel = pub.channel;
+    }
     if (pub.offset) {
       ctx.offset = pub.offset;
     }

src/client.proto.json

@@ -273,6 +273,10 @@
                     "time": {
                       "type": "int64",
                       "id": 9
+                    },
+                    "channel": {
+                      "type": "string",
+                      "id": 10
                     }
                   },
                   "reserved": [

src/types.ts

@@ -190,6 +190,11 @@ export interface PublicationContext {
   offset?: number;
   // tags is an extra key-value attached to publication, tags may be set when calling server publish API. 
   tags?: Record<string, string>;
+  // publicationChannel may be used to find out the real channel of publication, in most cases it
+  // matches channel field, but when wildcard subscriptions are used it may be different and contain
+  // a channel to which publication was published, thus differ from channel field (which is always a
+  // channel to which client subscribed to).
+  publicationChannel: string;
 }
 
 export interface ClientInfo {
@@ -260,7 +265,7 @@ export interface UnsubscribedContext {
 }
 
 export interface ServerPublicationContext {
-  // channel from which publication was received.
+  // subscription channel from which publication was received.
   channel: string;
   // data contains publication payload.
   data: any;
@@ -273,6 +278,11 @@ export interface ServerPublicationContext {
   offset?: number;
   // tags is an extra key-value attached to publication, tags may be set when calling server publish API. 
   tags?: Record<string, string>;
+  // publicationChannel may be used to find out the real channel of publication, in most cases it
+  // matches channel field, but when wildcard subscriptions are used it may be different and contain
+  // a channel to which publication was published, thus differ from channel field (which is always a
+  // channel to which client subscribed to).
+  publicationChannel: string;
 }
 
 export interface ServerJoinContext {