After looking at the log it appears that you are receiving messages that do not end in the '\r' terminator. Is this correct? From your previous post of the JSON config it seems you have the terminator set to '\r'.
If so that will make using this specific data source very difficult. The data source needs to have discrete messages to be able to use the regex matching effectively. The data source will hold all incoming data in a buffer until it sees the terminator, then it attempts to do matching on that. This means that if messages are received without the terminator they are held in the buffer until the terminator is found and then your regex matching is being done on all previous messages in addition to the recently received message with the terminator. I think this is why the datasource is appearing to 'hang', it is actually trying to do complex matching on long strings.
Another point is that it appears that your termination character is located inside some messages, this again will be a problem because the message will be assumed complete and matching will be done on a partial message. I may be wrong on this because of the way the logging is done it's impossible to see the message boundaries.
I've coded up another version of the module which will be more robust in handling this scenario but if what I am seeing is correct I don't think this will be a very effective solution to your problem. If I'm correct let me know and we can discuss other potential solutions. I've also added some additional logging that will show us the actual UTF8 string that is being matched on when matches are being performed.
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