[SOLVED] Any hint how to disable http Items, when http fails or catch the error without any log entry?

Setup, Configuration and Use Beginners
, ,
1
  • OH 2.5.8
  • Openhabian

With this item I check if a HUE lamp is available. This works great.
.item

String Light1StateOn "Lampe 1 - OH Schalter [MAP(huebridge.map):%s]" { http="<[http://192.168.x.xxx/api/<api-id>/lights/1:60000:JSONPATH($.state.on)]"}

But if this IP (the HUE Bridge) is not available, there are permanent error messages in the log.

log

2020-08-29 15:47:09.665 [ERROR] [org.openhab.io.net.http.HttpUtil    ] - Fatal transport error: java.net.NoRouteToHostException: Keine Route zum Zielrechner (Host unreachable)

Any hint how to disable this Item, when http fails or catch the error without any log entry?

Thanks!
Thomas

2

Not sure about your actual question, but as always, I think there is another way.

You could check the status of the Things.
https://www.openhab.org/docs/configuration/rules-dsl.html#thing-based-triggers

I think this would alleviate your issue.

1 Like
3

Yes, this looks good. It a complete different idea. Ok, I will check!

4

But you are HTTP version 1.x binding - there are no Things to look at.

You could manage this in rules using HTTP Action. Your rules can detect an error and decide not to poll again for a while.

1 Like
5

I rebuild everything into a rule and now i get the following questions:

a) What is the return value if the sendHttpGetRequest() fails and how could I check it. The return type is String. Logfile show me - null if http failed

2020-08-30 10:13:15.253 [ERROR] [.smarthome.model.script.actions.HTTP] - Fatal transport error: java.util.concurrent.ExecutionException: java.net.SocketTimeoutException: Connect Timeout
2020-08-30 10:13:15.257 [INFO ] [se.smarthome.model.script.Light1JSON] - null

.rules

[...]
val Light1JSON = sendHttpGetRequest("http://192.168.x.xxx/api/<api-id>/lights/1", 60000)
logInfo("Light1JSON", Light1JSON)
if ( Light1JSON === null ) {
} else {
 
}
[...]

log:

2020-08-30 10:36:00.033 [ERROR] [ntime.internal.engine.ExecuteRuleJob] - Error during the execution of rule 'Hue Bridge rule: Check state.on and state.reachable every minute (hue-bridge-changed.rules)': An error occurred during the script execution: index=1, size=1

b) Why can’t I use headers?

val headers = newHashMap("Cache-control" -> "no-cache")
val Light1JSON = sendHttpGetRequest("http://192.168.x.xxx/api/<api-id>/lights/1", headers, 60000)

log:

2020-08-30 10:00:00.012 [ERROR] [ntime.internal.engine.ExecuteRuleJob] - Error during the execution of rule 'Hue Bridge rule: Check state.on and state.reachable every minute (hue-bridge-changed.rules)': An error occurred during the script execution: Could not invoke method: org.eclipse.smarthome.model.script.actions.HTTP.sendHttpGetRequest(java.lang.String,int) on instance: null
2020-08-30 10:00:35.110 [INFO ] [el.core.internal.ModelRepositoryImpl] - Validation issues found in configuration model 'hue-bridge-changed.rules', using it anyway:
    // The value of the local variable headers is not used
6

As you’ve already discovered, the return is null.
That’s not a string though, it is just null.

So this will fail with the unhelpful mesage
An error occurred during the script execution: index=1, size=1
when Light1JSON is null, because logInfo() needs two strings.

You just need to rejig your if()

val Light1JSON = sendHttpGetRequest( ...)
if ( Light1JSON === null ) {
   logInfo("Light1JSON", "http response was null")
   ...
} else {
   logInfo("Light1JSON", "http response was " + Light1JSON)
  ... 
}

Headers are a recent addition to HTTP Actions.
I have an idea these are core Actions, and the core has been frozen at 2.5.0, so you won’t get headers until OH3

1 Like
7

exactly the right solution for me!
Many Thanks

Regards,
Thomas