Filter Parameters (v2)

This document outlines the filtering language added to the Allocation API in v1.96 of Kubecost, superseding the original filtering parameters (e.g. filterNamespaces=). One of the primary goals of the new filter language was to introduce support for "not equals" (e.g. namespace != kubecost) queries while maintaining extensibility.
Note: V1 filters will continue to be supported in all relevant APIs. APIs will first check for the filter= parameter. If it is present, V2 filters will be used. If it is not present, APIs will attempt to use V1 filters.

Filters overview

The supported filter fields as of v1.96 are:
  • cluster
  • node
  • namespace
  • controllerName
  • controllerKind (e.g. deployment, daemonset)
  • container
  • pod
  • services
  • label
  • annotation (same syntax as label, see examples)
The supported filter ops as of v1.96 are:
  • : (equality, or "contains" if an array type)
  • !: (inequality, or "not contains" if an array type)
Filter values are strings surrounded by ". Multiple values can be separated by commas ,, representing logical OR.
Each individual filter is separated by a +, representing logical AND.

Using filters

Filters exist under the filter= parameter in supported APIs. Supported APIs are currently:
Here are some example filters to see how the filtering language works:
  • namespace:"kubecost"+container:"cost-model" Return only results that are in the kubecost namespace and are for the cost-model container.
  • cluster:"cluster-one"+label[app]:"cost-analyzer" Return only results in cluster cluster-one that are labeled with app=cost-analyzer.
  • cluster!:"cluster-one" Ignore results from cluster cluster-one
  • namespace:"kubecost","kube-system" Return only results from namespaces kubecost and kube-system.
  • namespace!:"kubecost","kube-system" Return results for all namespaces except kubecost and kube-system.
For example, in an Allocation query:
The format is essentially: <filter field> <filter op> <filter value>

Formal grammar and implementation

To see the filter language's formal grammar and lexer/parser implementation, check out OpenCost's pkg/util/allocationfilterutil/v2.