yq/pkg/yqlib/operators.go

139 lines
4.3 KiB
Go

package yqlib
import (
"container/list"
"fmt"
"github.com/jinzhu/copier"
"gopkg.in/yaml.v3"
)
type operatorHandler func(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error)
func unwrapDoc(node *yaml.Node) *yaml.Node {
if node.Kind == yaml.DocumentNode {
return node.Content[0]
}
return node
}
func emptyOperator(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode) (Context, error) {
context.MatchingNodes = list.New()
return context, nil
}
type crossFunctionCalculation func(d *dataTreeNavigator, context Context, lhs *CandidateNode, rhs *CandidateNode) (*CandidateNode, error)
func resultsForRhs(d *dataTreeNavigator, context Context, lhsCandidate *CandidateNode, rhs Context, calculation crossFunctionCalculation, results *list.List, calcWhenEmpty bool) error {
if calcWhenEmpty && rhs.MatchingNodes.Len() == 0 {
resultCandidate, err := calculation(d, context, lhsCandidate, nil)
if err != nil {
return err
}
results.PushBack(resultCandidate)
return nil
}
for rightEl := rhs.MatchingNodes.Front(); rightEl != nil; rightEl = rightEl.Next() {
log.Debugf("Applying calc")
rhsCandidate := rightEl.Value.(*CandidateNode)
resultCandidate, err := calculation(d, context, lhsCandidate, rhsCandidate)
if err != nil {
return err
}
results.PushBack(resultCandidate)
}
return nil
}
func doCrossFunc(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode, calculation crossFunctionCalculation, calcWhenEmpty bool) (Context, error) {
var results = list.New()
lhs, err := d.GetMatchingNodes(context, expressionNode.Lhs)
if err != nil {
return Context{}, err
}
log.Debugf("crossFunction LHS len: %v", lhs.MatchingNodes.Len())
rhs, err := d.GetMatchingNodes(context, expressionNode.Rhs)
if err != nil {
return Context{}, err
}
if calcWhenEmpty && lhs.MatchingNodes.Len() == 0 {
err := resultsForRhs(d, context, nil, rhs, calculation, results, calcWhenEmpty)
if err != nil {
return Context{}, err
}
}
for el := lhs.MatchingNodes.Front(); el != nil; el = el.Next() {
lhsCandidate := el.Value.(*CandidateNode)
err := resultsForRhs(d, context, lhsCandidate, rhs, calculation, results, calcWhenEmpty)
if err != nil {
return Context{}, err
}
}
return context.ChildContext(results), nil
}
func crossFunction(d *dataTreeNavigator, context Context, expressionNode *ExpressionNode, calculation crossFunctionCalculation, calcWhenEmpty bool) (Context, error) {
var results = list.New()
var evaluateAllTogether = true
for matchEl := context.MatchingNodes.Front(); matchEl != nil; matchEl = matchEl.Next() {
evaluateAllTogether = evaluateAllTogether && matchEl.Value.(*CandidateNode).EvaluateTogether
if !evaluateAllTogether {
break
}
}
if evaluateAllTogether {
return doCrossFunc(d, context, expressionNode, calculation, calcWhenEmpty)
}
for matchEl := context.MatchingNodes.Front(); matchEl != nil; matchEl = matchEl.Next() {
innerResults, err := doCrossFunc(d, context.SingleChildContext(matchEl.Value.(*CandidateNode)), expressionNode, calculation, calcWhenEmpty)
if err != nil {
return Context{}, err
}
results.PushBackList(innerResults.MatchingNodes)
}
return context.ChildContext(results), nil
}
func createBooleanCandidate(owner *CandidateNode, value bool) *CandidateNode {
valString := "true"
if !value {
valString = "false"
}
node := &yaml.Node{Kind: yaml.ScalarNode, Value: valString, Tag: "!!bool"}
return owner.CreateChild(nil, node)
}
func createTraversalTree(path []interface{}, traversePrefs traversePreferences, targetKey bool) *ExpressionNode {
if len(path) == 0 {
return &ExpressionNode{Operation: &Operation{OperationType: selfReferenceOpType}}
} else if len(path) == 1 {
lastPrefs := traversePrefs
if targetKey {
err := copier.Copy(&lastPrefs, traversePrefs)
if err != nil {
panic(err)
}
lastPrefs.IncludeMapKeys = true
lastPrefs.DontIncludeMapValues = true
}
return &ExpressionNode{Operation: &Operation{OperationType: traversePathOpType, Preferences: lastPrefs, Value: path[0], StringValue: fmt.Sprintf("%v", path[0])}}
}
return &ExpressionNode{
Operation: &Operation{OperationType: shortPipeOpType},
Lhs: createTraversalTree(path[0:1], traversePrefs, false),
Rhs: createTraversalTree(path[1:], traversePrefs, targetKey),
}
}