I have recently set up a Raspberry Pi in my home with the openhabian image (running OH 2.1.0 stable).
Additionally I have installed Node-Red from the OpenHabian Configuration Tool.
After setting up the OH-Controller in the openhab2-node configuration in Node-Red (Protocol: http, Host: openhabianpi, Port: 8080). I get all my Items listed and I can select one.
However, I immedeately get the following error (red) in the debug tab (once):
TypeError: Cannot read property ‘close’ of undefined
Afterwards I repeatedly (every 2-3 seconds) get the following warning(?)(orange) in the debug tab:
msg : string 
If I delete the controller, the repeated warning messaged don’t stop, until I restart the Node-Red Service.
The Item state below the node then only shows a “?”.
I also tried to reach OpenHab with a second Pi (with an old setup, OH2.0) but I run into the same issue. The old OH2.0 setup however can be reached from both Node-Red setups, so I doubt this is an issue with Node-Red.
Did anybody ever run into a similar problem?
Any help, or even a pointer in the right direction would be appreciated.
Which version of Node-RED are you running? I noticed a similar issue after upgrading to the new .17 versions:
@Peter_De_Mangelaere Did you get a chance to test this and see if there were issues with all the changes in the new versions?
Personally, I ended up setting up a mosquitto server and switching to mqtt (was on my to do list anyways and when I started getting similar errors I just made the jump).
On my new Pi I’m running 0.17.4 and on my old one 0.15.1. I’m getting the issue on both systems.
For now I’m working with the MQTT Eventbus, too, but the openHAB nodes are much easier to use.
I wasn’t having any issues with the previous version so wonder if there was a change in OH about the same time. I was able to get an openhab-get nodes to pull fine, it was just the openhab-in nodes.
Agree that msqtt isn’t quite as convenient but I got to imagine it’s a little faster and less resource intensive then checking a REST api. It didn’t take too long to switch them all over just miss the -get nodes options and having to use flow variables instead. I never heard back from Peter on my previous posting so hopefully this one catches his attention and he can look into it.
OH 2.1 with node-red 0.17.3 on the same pi for a while now … without issues.
Is that the OH stable release? @germanbob are you running stable or snapshots? For me, I’m on the snapshots.
I’m running stable.
And I just tried out the openhab2 get-node, which works, but I still get the weird warning message every few seconds.
Alright so I figured out what the problem was by myself.
I looked into the source code of the openhab2-in nodes and noticed that they use a class called eventsource. This basically sets up a listener for “Server-Sent Events”.
However in my OpenHAB-Setup (and I’m assuming it will be the same for all OpenHABian setups) this was disabled by default.
1: Navigate to your openHAB application runtime directory.
For OpenHABian this will be /user/share/openhab2/runtime
For a manual installation it will be /opt/openhab2/runtime - I think
cd <application runtime path>
2: Open services.cfg with your preferred text editor
sudo nano services.cfg
3: add the line
4: save and restart.
After that everything worked like a charm for me.
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