Berry Scripting Language on Tasmota32 Driver: json.load(tasmota.read_sensors()) returns nil

[MechatronikMonkey]

PROBLEM DESCRIPTION

json.load(tasmota.read_sensors()) returns nil after tasmota.response_append(msg) in a driver

REQUESTED INFORMATION

Make sure your have performed every step and checked the applicable boxes before submitting your issue. Thank you!

• Read the Contributing Guide and Policy and the Code of Conduct
• Searched the problem in issues
• Searched the problem in discussions
• Searched the problem in the docs
• Searched the problem in the chat
• Device used (e.g., Sonoff Basic): generic
• Tasmota binary firmware version number used: [Tasmota 14.1.0 (release-tasmota32)]
  • [x ] Pre-compiled
  • Self-compiled
• Flashing tools used: VS-Code
• Provide the output of command: Backlog Template; Module; GPIO 255:

22:02:44.600 CMD: Backlog Template; Module; GPIO 255
22:02:44.626 RSL: RESULT = {"NAME":"ESP32-DevKit","GPIO":[1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,0,1,1,1,0,1,1,1,0,0,0,0,1,1,1,1,1,0,0,1],"FLAG":0,"BASE":1}
22:02:44.848 RSL: RESULT = {"Module":{"1":"ESP32-DevKit"}}
22:02:44.900 Hello World.
22:02:44.906 {'Time': '2024-06-19T22:02:44', 'VL53L0X': {'Distance': 18.8}}
22:02:45.105 RSL: RESULT = {"GPIO0":{"0":"None"},"GPIO1":{"0":"None"},"GPIO2":{"0":"None"},"GPIO3":{"0":"None"},"GPIO4":{"0":"None"},"GPIO5":{"0":"None"},"GPIO6":{"0":"None"},"GPIO7":{"0":"None"},"GPIO8":{"0":"None"},"GPIO9":{"0":"None"},"GPIO10":{"0":"None"},"GPIO11":{"0":"None"},"GPIO12":{"0":"None"},"GPIO13":{"0":"None"},"GPIO14":{"0":"None"},"GPIO15":{"0":"None"},"GPIO16":{"0":"None"},"GPIO17":{"0":"None"},"GPIO18":{"226":"Relay3"},"GPIO19":{"225":"Relay2"},"GPIO20":{"0":"None"},"GPIO21":{"224":"Relay1"},"GPIO22":{"0":"None"},"GPIO23":{"0":"None"},"GPIO24":{"0":"None"},"GPIO25":{"608":"I2C SCL1"},"GPIO26":{"640":"I2C SDA1"},"GPIO27":{"0":"None"},"GPIO32":{"0":"None"},"GPIO33":{"0":"None"},"GPIO34":{"0":"None"},"GPIO35":{"0":"None"},"GPIO36":{"0":"None"},"GPIO37":{"0":"None"},"GPIO38":{"0":"None"},"GPIO39":{"0":"None"}}
22:02:45.901 Hello World.
22:02:45.908 {'Time': '2024-06-19T22:02:45', 'VL53L0X': {'Distance': 18.9}}
22:02:46.901 Hello World.

  Configuration output here:

• If using rules, provide the output of this command: Backlog Rule1; Rule2; Rule3:

  Rules output here:

• Provide the output of this command: Status 0:

  STATUS 0 output here:

• Set weblog to 4 and then, when you experience your issue, provide the output of the Console log:

  Console output here:

Hello World.
nil
Hello World.
nil
Hello World.
nil
Hello World.
nil

TO REPRODUCE

Steps to reproduce the behavior:

Copy this to Berry Console:

class MyTestClass : Driver

    def DoIt()
        print("Hello World.")

        # Read Sensor data
        import json
        var MySensors = json.load(tasmota.read_sensors())
        print(MySensors)

    end

    def every_second()
        if !self.DoIt return nil end
        self.DoIt()

    end

    def web_sensor()
        import string
        var msg = string.format(
                  "Show this in Web UI")
        tasmota.web_send(msg)
    end

    def json_append() 
        import string
        var msg = string.format(",\"TestValue\":123}")
        tasmota.response_append(msg)
    end

end

test_instance = MyTestClass()
tasmota.add_driver(test_instance)

EXPECTED BEHAVIOUR

if you remove the response_append statement, the json.load can load the sensors as expected:

def json_append() 
        import string
        var msg = string.format(",\"TestValue\":123}")
        #tasmota.response_append(msg)
 end

SCREENSHOTS

If applicable, add screenshots to help explain your problem.

ADDITIONAL CONTEXT

It looks like that the response_append(msg) method kind of crashes json. If you try to parse a json string after response_append() you see the nil pointer.

(Please, remember to close the issue when the problem has been addressed)

[barbudor]

You have an unexpected closing bracket that break the JSON syntax
Correct would be

var msg = string.format(",\"TestValue\":123")

If you were just printing the result from tasmota.read_sensors() without trying to load it, you would have seen that your JSON was broken

There is no problem wiht tasmota.response_append()

You should better open a discussion instead of an issue when you don't have a qualified bug

[MechatronikMonkey]

Ok that is the problem... dohh ...

I printed the json string over and over again, but didn´t see the incorrect syntax...

Lol, what do you mean I don't have a qualified bug... I just thought it was a bug... I didn't know I needed to qualify somewhere first... Sorry, I am unworthy. Forgive me, honorable Tasmota gods, for I have sinned.

[barbudor]

The best way to qualify if it's a bug worth an issue is to first start a discussion
If someone say "right, looks like you found a bug" then you're good to go for the Issue 🤣

Enjoy Berry

[sfromis]

Beware that while the JSON syntax indeed gets better by keeping those {} balanced, what you produce is not how a Berry driver is meant to produce sensor values. The appropriate format would be including a name for the sensor object in the JSON, to house individual values, like:
var msg = ',"MyTest":{"TestValue":123}'
As you had no string formatting, no use for string.format.

But if you had, like a var named myvalue, you could use a f-string like:
var msg = f',"MyTest":{{"TestValue":{myvalue}}}'
A downside of this easy syntax is that you need to double "your own" {} in the string.

(I also took the opportunity to improve readability by having ' as string delimiter around the whole string, meaning that then it is no longer needed to escape as \").

BTW... I'm not saying can't work without, more like recommending to follow the usual JSON formatting, to be compatible with other tools handling the JSON payloads produced.

[MechatronikMonkey]

The best way to qualify if it's a bug worth an issue is to first start a discussion If someone say "right, looks like you found a bug" then you're good to go for the Issue 🤣

Enjoy Berry

Got it... I open a discussion first in the future...