operators-reference.md

When defining a condition, we can use any of the following operators.

• const
• getValue
• and
• or
• not
• equal
• sum
• forEach

const

Defines a constant value. It is normally used with the equal operator, in case we want to check that a field in the manifest equals to a value that we define (using the const operator).

const: <constant value>

getValue

Retrieves a value defined in the manifest. The <path> is a . (dot) separated path that references a field in the manifest. For example, .metadata.name. If the getValue is used nested within the forEach operator, by default it will take as a base context the item that the forEach is iterating. If you want to use the root of the manifest as the context, then you must add a $ at the beginning of the path. For example, $.metadata.name will always resolve to the metadata defined at the root level independently if the getValue is nested in a forEach or not.

# Refers to the latest context
getValue: .metadata.name

# Refers always to the root context
getValue: $.metadata.name

and

It performs an and operation on a list of elements. The list of elements can be explicitly defined (an actual yaml list) or implicitly defined. This last case is exemplified when the and consumes the result generated by the forEach operator.

and:
  - <elem1>
  - <elem2>
  - ...

and:
  forEach:
    ...

or

It performs an or operation on a list of elements. The list of elements can be explicitly defined (an actual yaml list) or implicitly defined. This last case is exemplified when the or consumes the result generated by the forEach operator.

or:
  - <elem1>
  - <elem2>
  - ...

or:
  forEach:
    ...

not

It negates the value of its argument.

not:
  <operator>

not:
  and:
    - ...

equal

Compares two elements and returns true if they are equal.

equal:
  - const: default
  - getValue: .metadata.namespace

sum

Sums the values of a list of elements. The list of elements can be explicitly defined (an actual yaml list) or implicitly defined. This last case is exemplified when the sum consumes the result generated by the forEach operator.

sum:
  - const: 1
  - const: 4

sum:
  forEach:
    ...

forEach

It's like a map operation. If executes the operation op for each element defined in elements. It returns the transformed list of elements. The getValue operator that lives within a forEach receives as context the current element that the forEach is iterating. In this example, .name resolves to the name of a container.

forEach:
  elements: {getValue: .spec.containers}
  op:
    equal:
      - const: my-side-car
      - getValue: .name