yq/pkg/yqlib/operator_unique.go

65 lines
1.8 KiB
Go

package yqlib
import (
"container/list"
"fmt"
"github.com/elliotchance/orderedmap"
yaml "gopkg.in/yaml.v3"
)
func unique(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
selfExpression := &ExpressionNode{Operation: &Operation{OperationType: selfReferenceOpType}}
uniqueByExpression := &ExpressionNode{Operation: &Operation{OperationType: uniqueByOpType}, Rhs: selfExpression}
return uniqueBy(d, context, uniqueByExpression)
}
func uniqueBy(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
log.Debugf("-- uniqueBy Operator")
var results = list.New()
for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
candidate := el.Value.(*CandidateNode)
candidateNode := unwrapDoc(candidate.Node)
if candidateNode.Kind != yaml.SequenceNode {
return Context{}, fmt.Errorf("Only arrays are supported for unique")
}
var newMatches = orderedmap.NewOrderedMap()
for _, node := range candidateNode.Content {
child := &CandidateNode{Node: node}
rhs, err := d.GetMatchingNodes(context.SingleReadonlyChildContext(child), expressionNode.Rhs)
if err != nil {
return Context{}, err
}
keyValue := "null"
if rhs.MatchingNodes.Len() > 0 {
first := rhs.MatchingNodes.Front()
keyCandidate := first.Value.(*CandidateNode)
keyValue = keyCandidate.Node.Value
}
_, exists := newMatches.Get(keyValue)
if !exists {
newMatches.Set(keyValue, child.Node)
}
}
resultNode := &yaml.Node{Kind: yaml.SequenceNode, Tag: "!!seq"}
for el := newMatches.Front(); el != nil; el = el.Next() {
resultNode.Content = append(resultNode.Content, el.Value.(*yaml.Node))
}
results.PushBack(candidate.CreateChild(nil, resultNode))
}
return context.ChildContext(results), nil
}