Hi @apollon77 !
I took a lot of inspiration from your java implementation of the client and created a python version to integrate directly in Home Assistant as a custom integration. Still a lot of testing to do and se how it performs over time but have at least come as far as it now shows 5 sensors (ph, orp, in_water?, ph_on and orp_on). https://github.com/dala318/python_ph803w
(Please let me know if you want any more/different credit to your solution shown in my project page)

I selected the approach to keep the connection open and poll the device constantly, could be that it brings to much strain on the HA manager and a better approach would be to only update every 60s or so and then reconnect every time.

For some reason the device discovery will not work in the Home Assistant environment (mine is running on PC in Hyper-V with a virtual switch that gives every VM it's own IP in my home network), probably has something to do with UDS broadcast ing and receiving response within HA. With the stand-alone lib/main it works...

@chaosbrother
Actually, when reading your initial message I think I understand your request a bit more. You want the device to connect to a local MQTT broker instead of the GizWits?
When Wiresharking the communication at startup I see that it starts by a http request to m2m.gizwits.com/<xxxxx> (exact string lost for now but can find out). The response to this request is just a string with the MQTT and LOG servers.
If you have an advanced router or connect the devive through a gateway you could modify the request to go to a local server and respond with your own server adresses.

After some sniffing of network traffic it seem that the device connects without encryption to the gizwits cloud via MQTT which is good news.

I tried some MQTT connection attempts to the gizwits broker but had to roll back to python since MQTT Exorer is locked to v3.1.1 and the broker is on v3.1 (non-compatible).
I can connect but have issues with subscriptions. Some are acked bit no data received.

After more googing I also found https://github.com/gizwits/gizwits-wechat-js-sdk which is my next attempt.

Hi. My german skills are very limited but I belive I have a similar idea as you ask for.

I have a PH-803w connected and can read values in the accompanied app but that is about it.
What I would like is to publish this data to my MQTT broker and make use of it in a bigger IoT network. I.e. show it in my control panel for the entire home, or only allow chlorine dosing while the filter pump is running.

When opening the device there is two pins from the ESP exposed, Rx/Tx, but yet I have not been able to read any data from them that makes sense. Normally those would be the flash program pins and debug logging and use serial interface. But regardless of Baudrate I try on my UART cable it seem only to be random values. More attempts to come, yet only look at it as ASCII, binary data is also a possibility.

Next way to tackle it is to connect the device over an network bridge (device <-> router <-> bridge <-> internet) with Wireshark or similar to sniff the traffic. At least it will expose the IP ports it used in the cloud communication, but likely the data will be over a secured socket and I'm stuck.

Feel free to comment my ideas or add new.