Dropdown list options separator, text when set from MQTT

[nagyrobi]

According to the docs \n has to be used between option items of a dropdown list.
I tried sending through MQTT to my hasp/plate/command/p2b4.options the string a\nb\nc\n\d and instead of dropping them to different items, it created a single item with \n's in it:

Another problem that the object does not update on the screen after posting the MQTT command, you have to switch page back and forth to see the changes.
if set from JSONL, it's OK.

[nagyrobi]

Similar issue:
setting "text":"\uF185" should display a sun icon, instead, it displays ]uF185 when set through MQTT.
if set from JSONL, it's OK.

left button set from MQTT, right button set from uploaded .jsonl file:
{"obj":"btn","id":2,"x":10,"y":40,"w":105,"h":90,"toggle":true,"text":"\uF185","text_font":28,"mode":"break","align":1}

[arovak]

I cannot reproduce with the latest build of the master branch. Can you show the logs from the device as when it received the MQTT command?

{"page":1,"obj":"btn","id":2,"x":10,"y":40,"w":105,"h":90,"toggle":"true","text":"\uF185","text_font":28,"mode":"break","align":1} {"page":1,"obj":"dropdown","id":3,"x":10,"y":150,"w":150,"h":40,"options":"Line 1\nLine 2\nLine 3\nline 4"}

log file of my test device
[Mar 24 12:56:40.273][81008/155944 48][54500/54680 1] MQTT RCV: hasp/test_plate/command/jsonl = {"page":1,"obj":"btn","id":2,"x":10,"y":40,"w":105,"h":90,"toggle":"true","text":"\uF185","text_font":28,"mode":"break","align":1} {"page":1,"obj":"dropdown","id":3,"x":10,"y":150,"w":150,"h":40,"options":"Line 1\nLine 2\nLine 3\nline 4"}

[nagyrobi]

You're using jsonl command. Try use text or options command directly, not jsonl.
Like I described in my first post.

[fvanroie]

To use an icon in a text you need to prefix the UTF-8 value with \u. To ensure proper decoding the payload should be used with a json or jsonl command.

As described here.

json and jsonl commands decode the escape characters into the correct UTF-8 bytes.

If you use .text or .options directly, you need to make sure that the bytes are already encoded properly in the mqtt payload.

[nagyrobi]

\u escape character is not recognized unfortunately in text, options. Home Assistant templates don't offer more than that imho.

[arovak]

You're using jsonl command. Try use text or options command directly, not jsonl.
Like I described in my first post.

still cannot reproduce with json.
[Mar 24 16:03:20.874][81008/155960 48][53948/54196 1] MQTT RCV: hasp/test_plate/command/json = ['p1b2.text=\uF185', ' p1b3.options=test 1\ntest 2\ntest 3'] [Mar 24 16:03:20.883][81008/155864 48][53948/54196 1] MSGR: p1b2.text=… [Mar 24 16:03:20.896][81008/155864 48][53948/54196 1] MSGR: p1b3.options=test 1 test 2 test 3

are you sure HA is sending the message in the correct form? What does the log of the device show?

[fvanroie]

Any modern programming language has the ability to encode/decode unicode bytes quite easily.

There are 2 distinct paths that the payload can follow: One is inside a json wrapper and the other one is raw bytes.
Forcing the raw bytes to also pass through a json 'parser and decoder' opens up other issues:

• hasp-lvgl operates on the raw mqtt payload as much as possible for optimizing speed and memory resources.
• An unnecessary json conversion just adds overhead if there are no escape characters needed.
• By adding escape sequences, you also need to use an unescape sequence for any backslashes you have.

I just don't think adding json parsers is the correct solution here, since this can be solved in other ways that don't burden the MCU.

[fvanroie]

Yes, he's doing a fabulous job with the custom component. We're all still learning here.
The take-away is that we can document this ourselves and help make a better integration possible!

[dgomes]

I just google "escape string jinja2" 😅

[htvekov]

Yep, Google is your friend (when they not selling your personal data 🤣)

It also took me some time to get this template working in HA. Never had to escape an escape character before. But HA's yaml parser 'eats' the first one processing the line.

payload_template: "{% if trigger.to_state.state == 'paused' %}\n  {{ '\\uf04b'\
        \ }}\n{% elif trigger.to_state.state == 'playing' %}\n  {{ '\\uf04c' }}\n\
        {% else %}\n  {{ '\\uf04d' }}\n{% endif %}" 

[fvanroie]

But HA's yaml parser 'eats' the first one processing the line.

I think it's because you use " as outer quotes. Maybe try to use ' as outer quotes and " for inner quotes.
That would explain the behavior.

[htvekov]

Spot on with that observation, @fvanroie.
Just tested, and indeed no need to 'escape' the escape character reverting to'as outer quotes. YAML syntax is a bitch sometimes (most times)... 😉 There also the pipe possibility as you mention.

[fvanroie]

Besides appending |e (pipe symbol + e) at the end of the template, the escape character can be either \x, \u or \U:

• Code points up to 0xFF should be encoded as "\xE6" in the template.

• Code points up to 0xFFFF should be encoded as "\uE6E8" in the template.
  Note: Use lowercase \u and exactly 4 hexadecimal digits.

• Code points above 0xFFFF must be encoded as "\U0001F5E9" in the template.
  Note: Use capital \U and exactly 8 hexadecimal digits.