Chart's wont show content, persistence is setup

[mircsicz (Mirco Schmidt)]

• Platform information:
  • Hardware: RPi 3
  • OS: OpenHABian
  • Java Runtime Environment: 1.8 u151
  • openHAB version: 2.2

I’ve created a group and have setup rrd4j persistence. The file’s are created but when I try to plot it all I see is an empty chart:
https://snag.gy/LXn6Hp.jpg

What am I missing?

[n_c]

Post your item and your persist-configuration please.
Use RestAPI to check the stored data.

[mircsicz (Mirco Schmidt)]

Hi n_c,

THX for the reply… here’s the Item’s I want to plot:

openhab> items list
HG_Temperatur (Type=NumberItem, State=5, Label=Temperatur, Category=null)
HG_Luftdruck (Type=NumberItem, State=977.00, Label=Luftdruck, Category=null)
HG_Luftfeuchtigkeit (Type=NumberItem, State=85, Label=Luftfeuchtigkeit, Category=null)
Diesel_BN_JET (Type=NumberItem, State=NULL, Label=Diesel BN Jet, Category=null, Groups=[diesel_group])
Diesel_BN_AVIA (Type=NumberItem, State=NULL, Label=Diesel BN AVIA, Category=null, Groups=[diesel_group])
diesel_group (Type=GroupItem, Members=2, State=NULL, Label=Diesel, Category=car)

And this is the related rrd4j.persist file:

// persistence strategies have a name and a definition and are referred to in the "Items" section


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


Items {
   HG_Luftdruck : strategy = everyMinute, restoreOnStartup
   HG_Luftfeuchtigkeit : strategy = everyMinute, restoreOnStartup
   HG_Temperatur : strategy = everyMinute, restoreOnStartup
   Diesel_BN_JET : strate`Preformatted text`gy = everyHour, restoreOnStartup
   Diesel_BN_AVIA : strategy = everyHour, restoreOnStartup
}

But how do I use the REST API to check the stored data?

EDIT: found this topic and from there tried to adopt the URL:

http://hab:8080/rest/persistence/items/ItemDiesel_BN_JET?serviceId=rrd4j&starttime=2018-13-03T12%3A00%3A00.000

[n_c]

REST Persistence

Query rrd4j via REST API

Hi all, to create a custom graph I try to query rrd4j with a given start time stamp (to be able to plot the last day, week, month … etc). When I try request using a starttime I always get exactly 24 data points. Strangely the time stamps (according to my calculations, which might be wrong) do not match the period I requested: http://haus:8080/rest/persistence/items/ItemServerCpuLoad?serviceId=rrd4j&starttime=2017-02-05T12%3A00%3A00.000 Reponse: { "name": "ItemServerCpuLoad", "datapoints"…

REST API GET persistence items

I dont understand following api behavior. If i send a get request on which items are available from persistence service i get an empty result and it makes no difference with or without url param serviceId set… [image] In case i request a specific item i get persisted data… [image] So that makes no sense for me. Or im missing some link here

[mircsicz (Mirco Schmidt)]

Seems the Diesel RRD file’s hold no data:

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

whilst the Yahoo Weather Data in HG_Temperatur seems to be fine:

http://hab:8080/rest/persistence/items/HG_Temperatur?serviceId=rrd4j

{"name":"HG_Temperatur","datapoints":"360","data":[{"time":1520937600000,"state":"8"},{"time":1520937840000,"state":"8"},{"time":1520938080000,"state":"8"},{"time":1520938320000,"state":"8"},{"time":1520938560000,"state":"8"},{"time":1520938800000,"state":"8"},{"time":1520939040000,"state":"8"},{"time":1520939280000,"state":"8"},{"time":1520939520000,"state":"8"},{"time":1520939760000,"state":"8"},

As I’ve configured MQTT persistence too I saw that “Diesel_BN_JET” & “Diesel_BN_AVIA” both have correct value’s:

[n_c]

https://docs.openhab.org/addons/persistence/rrd4j/readme.html#example
The strategy everyMinute must be used, otherwise no data will be persisted (stored).

@mircsicz

Diesel_BN_JET : stratePreformatted textgy = everyHour, restoreOnStartup

There is a error in the syntax also.

[mircsicz (Mirco Schmidt)]

Thank you can’t find the syntax error but as I changed it to everyMinute it now plot’s data…

[n_c]

@mircsicz

stratePreformatted textgy

Maybe it’s only in the post.

[mircsicz (Mirco Schmidt)]

It seems that was just a copy & paste issue in my posting…

[n_c]

If it’s solved, you can mark so.

[mircsicz (Mirco Schmidt)]

Sure, THX for the reminder