package yqlib import ( "container/list" yaml "gopkg.in/yaml.v3" ) // A yaml expression evaluator that runs the expression once against all files/nodes in memory. type Evaluator interface { EvaluateFiles(expression string, filenames []string, printer Printer, leadingContentPreProcessing bool, decoder Decoder) error // EvaluateNodes takes an expression and one or more yaml nodes, returning a list of matching candidate nodes EvaluateNodes(expression string, nodes ...*yaml.Node) (*list.List, error) // EvaluateCandidateNodes takes an expression and list of candidate nodes, returning a list of matching candidate nodes EvaluateCandidateNodes(expression string, inputCandidateNodes *list.List) (*list.List, error) } type allAtOnceEvaluator struct { treeNavigator DataTreeNavigator treeCreator ExpressionParser } func NewAllAtOnceEvaluator() Evaluator { return &allAtOnceEvaluator{treeNavigator: NewDataTreeNavigator(), treeCreator: NewExpressionParser()} } func (e *allAtOnceEvaluator) EvaluateNodes(expression string, nodes ...*yaml.Node) (*list.List, error) { inputCandidates := list.New() for _, node := range nodes { inputCandidates.PushBack(&CandidateNode{Node: node}) } return e.EvaluateCandidateNodes(expression, inputCandidates) } func (e *allAtOnceEvaluator) EvaluateCandidateNodes(expression string, inputCandidates *list.List) (*list.List, error) { node, err := e.treeCreator.ParseExpression(expression) if err != nil { return nil, err } context, err := e.treeNavigator.GetMatchingNodes(Context{MatchingNodes: inputCandidates}, node) if err != nil { return nil, err } return context.MatchingNodes, nil } func (e *allAtOnceEvaluator) EvaluateFiles(expression string, filenames []string, printer Printer, leadingContentPreProcessing bool, decoder Decoder) error { fileIndex := 0 firstFileLeadingContent := "" var allDocuments = list.New() for _, filename := range filenames { reader, leadingContent, err := readStream(filename, fileIndex == 0 && leadingContentPreProcessing) if err != nil { return err } if fileIndex == 0 { firstFileLeadingContent = leadingContent } fileDocuments, err := readDocuments(reader, filename, fileIndex, decoder) if err != nil { return err } allDocuments.PushBackList(fileDocuments) fileIndex = fileIndex + 1 } if allDocuments.Len() == 0 { candidateNode := &CandidateNode{ Document: 0, Filename: "", Node: &yaml.Node{Kind: yaml.DocumentNode, Content: []*yaml.Node{{Tag: "!!null", Kind: yaml.ScalarNode}}}, FileIndex: 0, LeadingContent: firstFileLeadingContent, } allDocuments.PushBack(candidateNode) } else { allDocuments.Front().Value.(*CandidateNode).LeadingContent = firstFileLeadingContent } matches, err := e.EvaluateCandidateNodes(expression, allDocuments) if err != nil { return err } return printer.PrintResults(matches) }