Selectors

Tags:

Selectors allow you to include or exclude resource objects when returned or reconciled by Jikkou.

Selector Expressions

Selectors are passed to Jikkou using the --selector CLI option. They allow you to define filtering logic to target specific resources during execution.

Selector expressions follow one of the following formats:

With an explicit selector:

<SELECTOR>: <EXPRESSION>

Using the default field selector (shorthand):

<KEY> <OPERATOR> VALUE`
<KEY> <OPERATOR> (VALUE1[, VALUE2, ...])

Note: The field: selector is the default, so it can be omitted when using field-based expressions.

Supported Selectors

Field (default)

The field selector filters resources based on arbitrary fields in the resource object.

field: <KEY> <OPERATOR> VALUE
field: <KEY> <OPERATOR> (VALUE1, VALUE2, ...)

Examples

Select resources with a label environment equal to staging or production:

field: metadata.labels.environement IN (staging, production)

or omitting the selector:

 metadata.labels.environement IN (staging, production)

Label

The label selector provides a convenient way to filter resources by their labels. This is often simpler and more intuitive than referencing label fields directly via the field selector.

Examples

Select resources with a label environment equal to staging or production:

label: environement IN (staging, production)

Expression (since: Jikkou v0.36)

The expr selector allows complex filtering using the Common Expression Language (CEL), providing powerful and expressive syntax for filtering by any resource attribute, including arrays and maps.

Examples

Select resources with the label env in staging or production:

expr: has(resource.metadata.labels.env) && resource.metadata.labels.env in ['staging', 'production']

Select Kafka topics with at least 12 partitions:

expr: resource.kind == 'KafkaTopic' && resource.spec.partitions >= 12

Select resources missing a specific annotation:

expr: !has(resource.metadata.annotations['mycompany.io/owner'])

Tip

Use the expr selector when you need advanced filtering logic, or when targeting nested fields, maps, or arrays.

Expression Operators

The following operators are supported for both field and label selectors:

Operator	Description
`IN`	Match if the field/label value is in the given list
`NOTIN`	Match if the field/label value is not in the given list
`EXISTS`	Match if the field/label is present
`MATCHES`	Match if the field/label value matches a regular expression
`DOESNOTMATCH`	Match if the field/label value does not match the regex

Note: These operators are not available for the expr selector, which uses CEL syntax instead.

Matching Strategies

When specifying multiple selectors, you can define how they are logically combined using the --selector-match option.

Available strategies:

ALL: The resource must match all selector expressions (logical AND).
ANY: The resource must match at least one selector (logical OR).
NONE: The resource must not match any selector (logical NOT).

Examples

jikkou get kafkatopics \
--selector 'metadata.name MATCHES (^__.*)' \
--selector 'metadata.name IN (_schemas)' \
--selector-match ANY

Last modified July 11, 2025: docs(site): update selectors page for 0.36 release (10402327)