Persist mqtt in rrd4j

[Arzeg (Hendrik)]

Hey folks, first of all i am quiet new to the OpenHAB community. I read a lot of topics and saw that the pros here are very helpfull IF we newbies read the docs but i actually cant find a solution for my problem.

I would like to show the Temperature and the Humidity from my ESP8266 with a DHT22 Sensor in a chart on my Sitemap and in the Android App.

I Installed the MQTT Broker on OpenHAB and Mosquitto as a Server on the Pi (OpenHAB and Mosquitto server are the same Pi). I can see the values ​​in MQTT.fx and on my Sitemap.

Now i want to make a chart for day, week, month and year. But i think mqtt is not saving the data in rrd4j.

rrd4j.persist:

Strategies {
        everyMinute: "0 * * * *?"
        everyHour: "0 0 * * *?"
        everyDay: "0 0 0 * *?"
        default = everyChange
}

Items {
        gDHT22_Sensor* : strategy = everyMinute, everyChange, restoreOnStartup
}

graph.items

Group gDHT22_Sensor "Chart Group"

Number chart period

Number FilaBox_Luftfeuchte "Humidity Filabox [% ​​.1f %%]" <humidity> (gDHT22_Sensor) {mqtt="<[mosquitto:/esp8266/sensor2_humidity_1]"}
Number FilaBox_Temp "Filabox temperature [% .1f °C]" <temperature> (gDHT22_Sensor) {mqtt="<[mosquitto:/esp8266/sensor2_temperature_1]"}

At this point i am not sure exactly what do i need to input for the broker name (called here mosquitto). Is mosquitto the right one here or is it a specific name or maybe localhost for the same System?

default.sitemap

        Frame label = "Filament Box" {
                Text item = ESP8266_DHT22_temperature label = "Temperatur [% .1f ° C]" icon = "temperature"
                Text item = ESP8266_DHT22_humidity label = "Humidity [% .1f %%]" icon = "humidity"

                Frame label = "Graphic of the values" icon = "chart" {
                        Switch item = chartPeriode label = "Period" mappings = [0 = "Day", 1 = "Week", 2 = "Month", 3 = "Year"]
                        Chart item = gDHT22_Sensor period = D refresh = 60000 service = "rrd4j" visibility = [chartPeriode == 0]
                        Chart item = gDHT22_Sensor period = W refresh = 60000 service = "rrd4j" visibility = [chartPeriode == 1]
                        Chart item = gDHT22_Sensor period = M refresh = 60000 service = "rrd4j" visibility = [chartPeriode == 2]
                        Chart item = gDHT22_Sensor period = Y refresh = 60000 service = "rrd4j" visibility = [chartPeriode == 3]
                }
        }

And finally some details from the REST API

GET / persistence / items / {itemname}

Curl

curl -X GET --header "Accept: application / json" "http://192.168.xxx.xxx:8080/rest/persistence/items/FilaBox_Temp?serviceId=rrd4j"

Request url

http://192.168.xxx.xxx:8080/rest/persistence/items/FilaBox_Temp?serviceId=rrd4j

Response body

{
  "name": "FilaBox_Temp",
  "datapoints": "0",
  "data": []
}

is that correct that the mqtt does not safe any data to rrd4j and i can saw that at the zero datapoints?

i appriciate any help
Greetings Hendrik

[opus (Jürgen Baginski)]

Welcome fo the openHAB forum

Your topic title gives your final goal, however you are not there yet. I suggest you go step by step.

You can see your MQTT devices report temperature and humidity via MQTTfx, so your problem is concerning openHAB and its connection to MQTT.
I have to assume you are using a openHAB version 2.5.xxx, hence you are using the MQTT binding version 2, however this one needs a different syntax to link items to thing channels ( which you probably haven’t created).
Most users use such devices flashed with Tasmota, so there are a lot of tutorials reflecting such, see Here

[hafniumzinc (T)]

I would also recommend going the Tasmota route, and using the V2 version of the MQTT binding: your Item configurations are for the V1 version of the MQTT binding. The following might also help:

[OH2] Tasmota flashed Sonoff Basic with DHT22 via MQTT

Overview I have a number of Sonoff Basic R2 switches around the house, attached to desk lamps, floor standing lamps, or spliced into the wiring for the outdoor porch light. As I already had the ESP8266 inside the Sonoffs at various locations, why not try and add a temperature sensor to them?! Note that whilst I used a DHT22, Tasmota supports a number of different sensors. Just ensure you choose the correct sensor within Tasmota’s Module parameters, and ensure that the name of the sensor is corr…

[Arzeg (Hendrik)]

not exactly. i can see the values in my sitemap too, not only in MQTTfx.

Yes. i am using 2.5.10 OpenHAB and the MQTT binding V2

the mqtt thing file is already created:

Bridge mqtt:broker:MosquittoMqttBroker "Mosquitto MQTT Broker" [
        host="127.0.0.1", 
        secure=false, 
        clientID="openHAB2"
]
{
        // DHT22 Luftfeuchtigkeitssensor fuer FilamentBox mit ESP8266
        Thing mqtt:topic:ESP8266_DHT22  "Filament Box" @ "Keller" {
                Channels:
                        Type number : Luftfeuchtigkeit "Luftfeuchtigkeit" [ 
                                stateTopic="/esp8266/sensor2_humidity_1"
                        ]
                        Type number  : Temperatur "Temperatur" [
                                stateTopic="/esp8266/sensor2_temperature_1"
                        ]
        }
}

Tasmota looks nice but i would like to try first the way i am already going. I think its just a little mistake anywhere.

If i cant go further i definetly try tasmota

@hafniumzinc i saw that link already but as i say i would like to go first the way i said. Where is the difference between the V1 and V2 items binding? On the Documentation site from MQTT V2 are no examples or anything about items

[opus (Jürgen Baginski)]

In case you are using the actual MQTT binding the above posted item definition are wrong (version 1 mqtt syntax!).
Check on PaperUI for the correct channel syntax in order to create a valid link.

Are the items you see on the sitemap members of the defined
gDHT22_Sensor group?
Did you check whether any .rrd files are created?

[hafniumzinc (T)]

@Arzeg

i saw that link already but as i say i would like to go first the way i said. Where is the difference between the V1 and V2 items binding?

As we mentioned, your Items are using the V1 syntax. For V2 it should say something like channel=... instead of mqtt=.... Check the links provided for the correct syntax.

@Arzeg

On the Documentation site from MQTT V2 are no examples or anything about items

Yes, annoys me too. Perhaps check this:

openhab/openhab-addons/blob/main/bundles/org.openhab.binding.mqtt.generic/xtend_examples.md

The above link will also show you that you have a minor syntax error in your Thing definition too, although it should still work! Just sort the Items out!

[Arzeg (Hendrik)]

I linked the “FilaBox_Luftfeuchte” and “FilaBox_Temp” to the group “gDHT22_Sensor” as you see in the graph.items file and then i used the group name in the .sitemap file, or do you mean something else?

.rrd file are created. I delete them after any change for a clear initialisation

@hafniumzinc
ahh its the channel thing for V2 thats good to know ^^

The GitHub link look good, i will try it

[hafniumzinc (T)]

Get your Items sorted, then make sure your Items display properly on your Sitemap/BasicUI, and only then concentrate on the rrd4j persistence!

[opus (Jürgen Baginski)]

…and when done with the correct items definition please post the respective lines and post which .rrd files ( names) are created. That will help looking into the persistence problem.

[Arzeg (Hendrik)]

my chart shows finally both data from the sensor the problem was the V1 Syntax

changed

Number FilaBox_Luftfeuchte "Humidity Filabox [% ​​.1f %%]" <humidity> (gDHT22_Sensor) {mqtt="<[mosquitto:/esp8266/sensor2_humidity_1]"}
Number FilaBox_Temp "Filabox temperature [% .1f °C]" <temperature> (gDHT22_Sensor) {mqtt="<[mosquitto:/esp8266/sensor2_temperature_1]"}

to

Number FilaBox_Luftfeuchte "Luftfeuchtigkeit Filabox [%.1f %%]" <humidity> (gDHT22_Sensor) {channel="mqtt:topic:ESP8266_DHT22:Luftfeuchtigkeit"}
Number FilaBox_Temp "Temperatur Filabox [%.1f °C]" <temperature> (gDHT22_Sensor)  {channel="mqtt:topic:ESP8266_DHT22:Temperatur"}

i know i have Celsius and percentage values in one chart, but for me is it perfect.
Now there is one problem left. I cant see the chart on the Android App. I think its because i need to click the “TAG” “WOCHE” “MONAT” or “JAHR” to see the chart, but i cant see the buttons on the App. The only thing the App shows me is “Grafik der Werte” nothing else.

oh and @opus the .rrd files wich one are created are the both item values (FilaBox_Luftfeuchte.rrd and FilaBox_Temp.rrd)

[opus (Jürgen Baginski)]

So you have solved the persistence problem.

On the problem with missing buttons on the android app:

You need a initial selection in order to show a chart because you haven"t set a chart for the case that the selection hasn’t been made ( ==“NULL”). Put that one additionally to a present case.
I can’t say why the buttons do not show, my sitemap looks like yours exempt that I don’t have the frame with the charts in another frame, mine is a following frame.
Unless you have changed the above posted sitemap.

[Arzeg (Hendrik)]

Got it! I add the

chartPeriode=="Uninitialized"

parameter to the first Chart.

The Problem with the buttons was the Frame in the Frame. I Put it into one single Frame now and it is working well

Thanks for all your help @opus @hafniumzinc this chart and the persistence took me a couple of days, but i learned a lot