9. Datum Filters¶
Datum Filters are services that manipulate datum generated by SolarNode plugins before they are uploaded to SolarNet. See the general Datum Filters section for more information about how datum filters work and what they are used for.
9.1 Global Datum Filters¶
Global Datum Filters are applied to datum just before posting to SolarNetwork. Once an instance is created, it is automatically active and will be applied to datum. This differs from User Datum Filters, which must be explicitly added to a service to be used, either dircectly or indirectly with a Datum Filter Chain.
Click the Manage button next to any Global Datum Filter component to create, update, and remove instances of that filter.
9.2 Datum Queue¶
All datum generated by SolarNode plugins are added to the Datum Queue for processing. The datum are processed in the order they are added to the queue. Datum Filters are applied to each datum, each filter's result passed to the next available filter until all filters have been applied.
The Datum Queue section of the Datum Filters page shows you some processing statistics and has a couple of settings you can change:
| Setting | Description |
|---|---|
| Delay | The minimum amount of time to delay processing datum after they have been added to the queue, in milliseconds. A small amount of delay allows parallel datum collection to get processed more reliably in time-based order. The default is 200 ms and usually does not need to be changed. |
| Datum Filter | The Service Name of a Datum Filter component to process datum with. See below for more information. |
The Datum Filter setting allows you to configure a single Datum Filter to apply to every datum captured in SolarNode. Since you can only configure one filter, it is very common to configure a Datum Filter Chain, where you can then configure any number of other filters to apply.
9.3 Global Datum Filter Chain¶
The Global Datum Filter Chain provides a way to apply explicit User Datum Filters to datum just before posting to SolarNetwork.
| Setting | Description |
|---|---|
| Active Global Filters | A read-only list of any created Global Datum Filter component Service Name values. These filters are automatically applied, without needing to explicitly reference them in the Datum Filters list. |
| Available User Filters | A read-only list of Service Name values of User Datum Filter components that have been configured. You can copy any value from this list and paste it into the Datum Filters list to activate that filter. |
| Datum Filters | The list of Service Name values of User Datum Filter components to apply to datum. |
9.4 User Datum Filters¶
User Datum Filters are not applied automatically: they must be explicitly added to a service to be used, either dircectly or indirectly with a Datum Filter Chain. This differs from Global Datum Filters which are automatically applied to datum just before being uploaded to SolarNet.
Click the Manage button next to any User Datum Filter component to create, update, and remove instances of that filter.