fix: on invalid package only emit error if listeners available

README.md

@@ -119,6 +119,8 @@ Any use of the source code and related documents of this repository in applicati
 * 2024-03-19: 1.9.5  - fix: update dependencies in package-lock
 * 2024-05-24: 1.9.6  - fix: catch exception when server sends invalid/incomplete json in subscription (Bug849302).
                      - fix: add more tests to handle node address with invalid symbols
+* 2024-12-06: 1.9.7  - fix: update dependencies in package-lock                     
+                     - fix: further improve resilience on invalid data from server
 ```
 
 ## About

lib/CtrlxDatalayerSubscription.js

@@ -435,7 +435,9 @@ class CtrlxDatalayerSubscription extends EventEmitter {
               setTimeout(()=>this.emit('update', payload, e.lastEventId), 0);
             }
           } catch (err) {
-            this.emit('error', new Error(`Error parsing update event: ${err.message}`));
+            if (this.listeners('error').length > 0) {
+              this.emit('error', new Error(`Error parsing update event: ${err.message}`));
+            }
           }
 
         });
@@ -452,7 +454,9 @@ class CtrlxDatalayerSubscription extends EventEmitter {
               setTimeout(()=>this.emit('keepalive', payload, e.lastEventId), 0);
             }
           } catch (err) {
-            this.emit('error', new Error(`Error parsing keepalive event: ${err.message}`));
+            if (this.listeners('error').length > 0) {
+              this.emit('error', new Error(`Error parsing keepalive event: ${err.message}`));
+            }
           }
         });