The initial idea for this feature comes from the `categories` fields that we
can find in the `summary` object of the RadosGW API. Each user has a
`categories` attribute in the response; in the `categories` list, we can find
the object that presents ain a granular fashion the consumption of different
RadosGW API operations such as GET, PUT, POST, and may others.
In that context, and having in mind that we have APIs with similar data
structures, we developed an extension for the dynamic pollster that enables
multi-metric processing for a single pollster. It works as follows.
The pollster name will contain a placeholder for the variable that
identifies the "submetric". E.g. `dynamic.radosgw.api.request.{category}`.
The placeholder `{category}` indicates the object attribute that is in the list
of objects that we use to load the sub metric name. Then, we must use a special
notation in the `value_attribute` configuration to indicate that we are dealing
with a list of objects. This is achieved via `[]` (brackets); for instance, in
the `dynamic.radosgw.api.request.{category}`, we can use `[categories].ops`
as the `value_attribute`. This indicates that the value we retrieve is a list
of objects, and when the dynamic pollster processes it, we want it (the
pollster) to load the `ops` value for the sub metrics being generated
Depends-On: https://review.opendev.org/#/c/694519/
Change-Id: I6ed4632f209ac51a07687476ca316212659d72bb
Signed-off-by: Rafael Weingärtner <rafael@apache.org>
4e3c12968d