[Solved] log-reader plugin - logWatcher device does not update correctly

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Hey,

I tried to set up a logWatcher device to parse the data from the miflora plant monitor into pimatic. The used script is working well and I get my logs to where I want to have them and read them once, but if the logfile changes the device is not updated.
I tried multiple logWatcher devices with different logfiles, but all behave the same way: In case I restart pimatic or recreate the device it reads the content from the logfile and shows correct values. But when the logfile changes (new data from sensor) it is ignored. Do I have to invoke a manuall refresh somehow?

here my device config:

{
      "file": "/home/pi/miflora/wohnzi.log",
      "attributes": [
        {
          "name": "Temperature",
          "type": "number",
          "unit": "°C",
          "acronym": "🌡"
        },
        {
          "name": "Moisture",
          "type": "number",
          "unit": "%",
          "acronym": "💦"
        },
        {
          "name": "Light",
          "type": "number",
          "unit": "lux",
          "acronym": "💡"
        },
        {
          "name": "Conductivity",
          "type": "number",
          "unit": "us/cm"
        },
        {
          "name": "Battery",
          "type": "number",
          "unit": "%",
          "acronym": "🔋"
        }
      ],
      "lines": [
        {
          "match": "Temperature: (.+)",
          "predicate": "miflora.temperature",
          "Temperature": "$1"
        },
        {
          "match": "Moisture: (.+)",
          "predicate": "miflora.moisture",
          "Moisture": "$1"
        },
        {
          "match": "Light: (.+)",
          "predicate": "miflora.light",
          "Light": "$1"
        },
        {
          "match": "Conductivity: (.+)",
          "predicate": "miflora.conductivity",
          "Conductivity": "$1"
        },
        {
          "match": "Battery: (.+)",
          "predicate": "miflora.battery",
          "Battery": "$1"
        }
      ],
      "xAttributeOptions": [],
      "id": "miflora-wohnzi",
      "name": "Pflanzen Wohnzimmer",
      "class": "LogWatcher"
    },

and one of the logfiles:

pi@raspberrypi:~/miflora $ nano wohnzi.log
  GNU nano 2.2.6             Datei: wohnzi.log

Getting data from Mi Flora
FW: 2.8.6
Name: Flower care
Temperature: 19.6
Moisture: 64
Light: 52
Conductivity: 1070
Battery: 100

@Anduril said in log-reader plugin - logWatcher device does not update correctly:

Do I have to invoke a manuall refresh somehow?

How do you write data to the log file? Do you overwrite the contents of the log file each time you write to the log or is new data appended to the log file? If it overwritten each time this will not work. Can you please show the script producing wohnzi.log?

hey @mwittig,

the script creating the log file is from the thread for the xiaomi miflora (https://forum.pimatic.org/topic/2588/xiaomi-miflora-plant-sensor). The script simply overwrites the old values in the log.
I tested to append the new data manually to the log, and that works well. I just don’t know how the others are dealing with that, as they said to directly use the log output of the script.
My situation is a little special, as I have the script running on one rpi and pimatic and the logreader on another. So I use scp to copy the log to the pimatic rpi. Maybe I can copy it and append to another .log with an crontab command… do you have a suggestion for that?
And how does the logreader react to a running logfile, so adding 1 dataset and deleting an old one to keep the log size smaller?

ok I did a short googling… and the result is to use >> instead of > when specifying the output. This works now, thanks a lot @mwittig for pointing me to that.
Still the question what to do to keep the logfile small. Do you have a good way to do this?

@Anduril said in log-reader plugin - logWatcher device does not update correctly:

Still the question what to do to keep the logfile small. Do you have a good way to do this?

Yes, you can use truncate, e.g. truncate -s0 yourLogFile or use the :> I/O operator with bash to truncate the file, e.g. :> yourLogFile.

# the following line will create or truncate the file 'yourLogFile'
:> yourLogFile
# append the output to the log file
echo $stateVariable >> yourLogFile

See also https://forum.pimatic.org/topic/2396/pimatic-log-reader-updates-variables-just-at-device-creation/9

Note, even though the : basically is a no-op, it is essential to place it before the > operator as this will let bash truncate the file rather than overwriting the file. Personally, I prefer using truncate -s0 yourLogFile as this is more literate.

thanks a lot @mwittig

Now, that everything seems to be working with the device I tried to create a rule to inform me when my plants get dry… but when miflora.moisture <20 always says Oops...Expected one of: "and", "or", "]".
Does this mean it treats this as kind of boolean? I thought to have it as a number…

already tried WHEN moisture of miflora < 20 THEN ... ?

same result, it does not work…
Oops... Could not find an provider that decides next predicate of "moisture of miflora-bad <20".

well that’s strange… when constructing the same with gui and selecting all parameters as before it works now…
well my problem is solved, but I don’t understand why/how…

@Anduril said in log-reader plugin - logWatcher device does not update correctly:

well my problem is solved, but I don’t understand why/how…

Sometimes it is just an extra space in between the literals causing the problem