Cumulocity Notification 2.0 big messages splitted

Product/components used and version/fix level:

Cumulocity prod 1018.*

Detailed explanation of the problem:

Using notification 2.0, when a message is bigger than 8192B, it is splitted in several messages.
How can one knows that a message is following a previous message, but more precisely, which message? Such messages don’t have headers, so you know that they are another part of a bigger message, but I can’t find a hint to help understand how to merge thoses messages.

Error messages / full error message screenshot / log file:

No error, just messages that I don’t know what to do with.

Question related to a free trial, or to a production (customer) instance?


In the end the issue is simply that I’m using Spring’s WebSocketHandler with:

public boolean supportsPartialMessages() {
  return true;

Setting this to false and setting a bigger size limit for the text messages for the session (WebSocketSession.setTextMessageSizeLimit() for example in the afterConnectionEstablished() method) solved the issue.
The good news is that it means that Cumulocity webSocket implementation supports partial messages :slight_smile:
If let to true, I would need to check the value of WebSocketMessage.isLast().

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