"unable to load data" error with REST data set

[agaldemas]

Describe the bug
using Knowage 7.3.0-S deployed with docker-compose.

any widget (table or map) on REST data set querying Orion Context Broker, give an error
"Unable to load data from dataset
Please check dataset & widget config"

To Reproduce
Steps to reproduce the behavior:

1. create REST data set to an Orion Context Broker, check it's OK with Preview, check metadata is OK
2. in a document, add the previous REST data set
3. add a widget (table or map), save it
4. See error "Unable to load data from dataset
   Please check dataset & widget config", and no data in the widget
   we can see an error in the chrome debugger

Expected behavior
widgets should work correctly

Screenshots

Desktop :

• OS: MacOS
• Browser: chrome
• Version 88

Additional context
the issue seems not browser dependant, since the same error raise with Safari and Firefox !
the problem is the same with docker image version knowage-server-docker:7.4.0-SNAPSHOT, or 7.2
therefore it seems to be something i miss in the configuration of the data set itself or in the document

[agaldemas]

Humm ! found the issue, it was a cache_ds configuration issue...
in docker image on dockerhub cache_ds is not properly configured....
Anyway this problem is not properly reported to the user, the error message is not enough, I had to have a look at the logs in the container to discover the reason of the error

[agaldemas]

May be it's a recommendation to add for an admin, to check the cache (cache_ds) data source is working !

[kerny3d]

Hi,

thank you for reporting it. We will try to update the documentation and we will update the docker-compose descriptors to add another DB for the cache.