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Quantity

What it does

Converts between a Kubernetes resource.Quantity string ("500m", "2", "1Gi") and an integer millivalue (Quantity.MilliValue()). Compile infers which side is the string from the schemas.

When to use it

A field that stores a resource request or limit as a Quantity string on one API version and as an integer number of millicores (or milli-units) on another. NumericScale only rescales numbers; it cannot parse "500m".

Integer → canonical Quantity string is lossy

Parsing a Quantity string into a millivalue is exact at milli resolution (Quantity.MilliValue()). Amounts finer than 1m round to that granularity. Writing the millivalue back out uses the canonical Quantity spelling ("500m"), which is not always the original string ("0.5" and "500m" are the same Quantity). That direction requires acknowledgeLossy: true.

Example

The hub's cpuRequest Quantity string is stored as millicores on the v1 spoke:

spec:
  properties:
    cpuRequest:
      type: string

spec:
  properties:
    cpuMillis:
      type: integer

Rule

- strategy: Quantity
  quantity:
    hubPath: spec.cpuRequest
    spokePath: spec.cpuMillis
  acknowledgeLossy: true
  reason: >-
    integer millivalues re-format as the canonical Quantity string (500m),
    which may differ from an equivalent spelling such as 0.5.

Objects

spec:
  cpuRequest: "500m"

spec:
  cpuMillis: 500

"500m" happens to be canonical, so this particular sample round-trips. A hub value of "0.5" converts to the same 500 millicores and comes back as "500m" — that is the acknowledged-lossy direction, and convctl test is how you see it on real data.