yq/pkg/yqlib/data_tree_navigator.go

42 lines
1.1 KiB
Go

package yqlib
import (
"fmt"
logging "gopkg.in/op/go-logging.v1"
)
type DataTreeNavigator interface {
// given the context and a expressionNode,
// this will process the against the given expressionNode and return
// a new context of matching candidates
GetMatchingNodes(context Context, expressionNode *ExpressionNode) (Context, error)
}
type dataTreeNavigator struct {
}
func NewDataTreeNavigator() DataTreeNavigator {
return &dataTreeNavigator{}
}
func (d *dataTreeNavigator) GetMatchingNodes(context Context, expressionNode *ExpressionNode) (Context, error) {
if expressionNode == nil {
log.Debugf("getMatchingNodes - nothing to do")
return context, nil
}
log.Debugf("Processing Op: %v", expressionNode.Operation.toString())
if log.IsEnabledFor(logging.DEBUG) {
for el := context.MatchingNodes.Front(); el != nil; el = el.Next() {
log.Debug(NodeToString(el.Value.(*CandidateNode)))
}
}
log.Debug(">>")
handler := expressionNode.Operation.OperationType.Handler
if handler != nil {
return handler(d, context, expressionNode)
}
return Context{}, fmt.Errorf("Unknown operator %v", expressionNode.Operation.OperationType)
}