[Feature] Create a lookup operation

[eddycharly]

Create a lookup operation to read one or more resources from the cluster.

[siddhikhapare]

/assign

[eddycharly]

The purpose of this operation would be to read one (or more) resources from the cluster.

Then create outputs based on the retrieved resources.

I wonder if it would make sense to do that directly in assert and/or apply operations 🤔

[siddhikhapare]

The purpose of this operation would be to read one (or more) resources from the cluster.

Then create outputs based on the retrieved resources.

I wonder if it would make sense to do that directly in assert and/or apply operations 🤔

I'll give it a try and see how it works out.

[eddycharly]

@siddhikhapare i started working on this in #1089

[siddhikhapare]

@eddycharly I used this to read resources from cluster as helm have lookup function

type Lookup struct {
    // Timeout for the operation. Overrides the global timeout set in the Configuration.
    // +optional
    Timeout *metav1.Duration `json:"timeout,omitempty"`
    // Namespace defines the namespace in which to search for the resources.
    // +optional
    Namespace string `json:"namespace,omitempty"`
    // Labels defines the labels to filter the resources.
    // +optional
    Labels map[string]string `json:"labels,omitempty"`
    // Kind defines the kind of resources to retrieve.
    // +optional
    Kind string `json:"kind,omitempty"`
    // Name defines the name of the resource to retrieve.
    // +optional
    Name string `json:"name,omitempty"`
    // APIVersion defines the API version of the resource to retrieve.
    // +optional
    APIVersion string `json:"apiVersion,omitempty"`
    // Template determines whether resources should be considered for templating.
    // +optional
    Cluster string `json:"cluster,omitempty"`
    // Cluster defines the target cluster (default cluster will be used if not specified and/or overridden).
    // +optional
    Template *bool `json:"template,omitempty"`
    // DryRun determines whether the operation should be performed in dry run mode.
    // +optional
    DryRun *bool `json:"dryRun,omitempty"`
    // Expect defines a list of matched checks to validate the operation outcome.
    // +optional
    Expect []Expectation `json:"expect,omitempty"`
}

[eddycharly]

@siddhikhapare the only thing i'm not sure about is how to deal with multiple resources (when working with labels for example)

[siddhikhapare]

@siddhikhapare the only thing i'm not sure about is how to deal with multiple resources (when working with labels for example)

@eddycharly can we create function to search resources of cluster by labels which specified in a Lookup struct using labelSelector?
It may be not needed here. You have completed lookup operation only test are remaining.

[eddycharly]

I'm still not sure how it will be useful, and we already have a get operation so 🤷
I think i will post pone to a later version until we find a use case for it.

[siddhikhapare]

I'm still not sure how it will be useful, and we already have a get operation so 🤷 I think i will post pone to a later version until we find a use case for it.

Yeah, Sure.

[cbandy]

I would like very much to be able to use outputs on the get operation. At present I use a command or script operator to run kubectl get.

Were this implemented, I would expect the resulting JMESPath context @ to differ between using get.name and get.selector:

• get.name, found: @ is the object
• get.name, not found: error? @ is null?
• get.selector, found some: @ is an array of objects
• get.selector, found none: @ is an empty array