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Update properties of controller service in Nifi

New Contributor

Dear NiFi enthousiasts,


I'm configuring a flow where I make a connection with several websockets. Each ws-url contains a unique authentication token obtained via a seperate http-request and is now manually added to the ws-url. Whenever the connection is lost for more than 20 min, my token becomes invalid and I have to manually request new tokes and update the JettyWebSocketClient for each of the websocket connections. this is time consuming and error-prone. To avoid this, I would like to automate this.


I was thinking I could store the token in an attribute and pass it to the controller but apparently you cannot pass flow-file attributes to a controller. And on top of that you have to disable before you can update.

So, the question is, how can I update the ws-url in the JettyWebSocketClient with new tokens?


In order to get the tokens, I need to do a http GET request with x-www-form-urlencoded headers, a signIn command, username and password. This returns a JSON with the token. I replaced the real token with "token".

  "data": {
    "clientToken": "token"






Screenshot NiFi Flow.png


Master Guru



The JettyWebSocketClient NiFi controller does support NiFi EL (variable registry only)  in the WebSocketURI property.  This means that you can means you could use for example ${token} in the URL you set in this Controller service.  Variables can be set on the process group. 


So you have two option here and both involve using the NiFi Rest-API.
Both start with obtaining the new token (perhaps via a rest-api call using the invokeHTTP processor?


1. Use NiFi's rest-API to stop, modify, and start theJettyWebSocketClient

2. Use NiFi's rest-API to modify a NiFi variable set on a process group.  Advantage here is the token variable can be used by multiple processors with the process group (or sub-process groups) where it was defined.  Allowing you to make only one update.


So consider building a flow that upon failure you trigger an invokeHTTP to get a new token and then another invokeHTTP to update the variable via NiFi's rest_API.  Then loop failed FlowFile back to processor that failed to try again.

When working with NiFi's rest-api, it is helps to use your browser's developer tools to capture the rest api calls as you manually perform them via the NiFi UI.  NiFi's rest-api documentation is also available within the embedded docs of your NiFi installation (global menu --> Help).


Hope this helps,


New Contributor

Hey Matt,


Thanks for your reply. This really helps a lot.

If this leads to a solution, I will post the results here and accept as solution.



New Contributor

Dear @Tine,


I have exactly the same use case. Have you implemented the proposed solutions from above? I would really appreciate it if you could share your experience!


Thanks in advance!