The string data can vary greatly - can be longer, shorter, contain what I am looking for or not, contain the line more than once (unlikely, but would be interested in the last occurrence):
I think this should happen automatically for the REGEX binding. REGEX is often used chained to other transformations to filter out messages that don’t meet a criteria.
This might prove challenging as the REGEX provided through an OH transformation does not offer the full set of REGEX capabilities and options and it behaves a little differently (e.g. it uses the first group to identify what part you want to extract from the String). I think you can cause it to start at the end by appending $ after your capture group though. If not, you might need to process this data in a Rule or SCRIPT transformation where you can access the full and standard REGEX capabilities.
.sync time:(\d/\d*\ \d*:\d*:\d*)$.*
Once you get the REGEX right this should just happen. The first matching group is what gets returned.
Need more details on what specifically you mean by “work on”.
var Previous_Date_Time, New_date_Time, Date_Time_Difference;
//log:set DEBUG org.openhab.automation.script.ui.SunSynk_Date_Time_Change
console.debug((['Current Value of SunSynk_Current_DateTime ',items.getItem('SunSynk_Current_DateTime').state,'Current Value of previous state is: ',event.oldItemState?.toString(),'Current Value of new state is: ',event.itemState?.toString()].join('')));
Previous_Date_Time = (time.toZDT(event.oldItemState?.toString()));
New_date_Time = (time.toZDT(event.itemState?.toString()));
console.debug((['Previous Date and Time is - ',Previous_Date_Time,' New Date and Time is - ',New_date_Time].join('')));
Date_Time_Difference = (time.ChronoUnit.MINUTES.between(Previous_Date_Time,New_date_Time));
console.debug(('Date and Time difference is (minutes) - ' + String(Date_Time_Difference)));
items.getItem('SunSynk_Time_Diff_Mins').sendCommand(Date_Time_Difference);
if (Date_Time_Difference > 2) {
actions.notificationBuilder(('SunSynk Time Difference More than 2 minutes - ' + String(Date_Time_Difference))).withIcon('alarm').withTag('info').send()
}
If it’s a DateTime type Item I think the Item would either not be updated or updated to NULL or UNDEF. There is no such thing as an “empty” state for a DateTime Item.
However, if you need the Item to be updated to NULL or UNDEF (assuming the update is not just ignored) you can chaing the REGEX transform to a SCRIPT transform that converts blank to NULL.
JS:| (input == "") "NULL" ? input
That’s an inline transform so in the UI you would just add that as a new transform below the REGEX one. @jimtng made chaining transformations in the UI much nicer, no more strange untypeable characters required.
This is a quirk" of the way the web site I am scraping works.
The web site is a “rolling” log of events. It seems to work on a buffer type system where the page resets when the buffer fills up, so if the HTTP Binding polls the page at that specific time there is a chance (actually quite frequent) that there is no sync time:2024/11/14 19:44:09entry at all.
When this happens the REGEX linked item is updated with an empty string.
I am not interested in these empty strings - only what the most recent sync time value was.
So I need to ignore any empty updates and only process actual values.
Hence the rule that I showed above.
Happy to hear if there are any better ideas to achieve this?
If the REGEX returns the empty string update the Item to it’s current state.
Any rule that does something with the DateTime just needs to trigger on the Item changeing. Such rules will only trigger when there is a sync time and that time is different from the Item’s current state.
