yq/pkg/yqlib/path_tokeniser.go

404 lines
13 KiB
Go

package yqlib
import (
"fmt"
"strconv"
lex "github.com/timtadh/lexmachine"
"github.com/timtadh/lexmachine/machines"
)
func skip(*lex.Scanner, *machines.Match) (interface{}, error) {
return nil, nil
}
type TokenType uint32
const (
OperationToken = 1 << iota
OpenBracket
CloseBracket
OpenCollect
CloseCollect
OpenCollectObject
CloseCollectObject
TraverseArrayCollect
)
type Token struct {
TokenType TokenType
Operation *Operation
AssignOperation *Operation // e.g. tag (GetTag) op becomes AssignTag if '=' follows it
CheckForPostTraverse bool // e.g. [1]cat should really be [1].cat
}
func (t *Token) toString() string {
if t.TokenType == OperationToken {
log.Debug("toString, its an op")
return t.Operation.toString()
} else if t.TokenType == OpenBracket {
return "("
} else if t.TokenType == CloseBracket {
return ")"
} else if t.TokenType == OpenCollect {
return "["
} else if t.TokenType == CloseCollect {
return "]"
} else if t.TokenType == OpenCollectObject {
return "{"
} else if t.TokenType == CloseCollectObject {
return "}"
} else if t.TokenType == TraverseArrayCollect {
return ".["
} else {
return "NFI"
}
}
func pathToken(wrapped bool) lex.Action {
return func(s *lex.Scanner, m *machines.Match) (interface{}, error) {
value := string(m.Bytes)
value = value[1:]
if wrapped {
value = unwrap(value)
}
log.Debug("PathToken %v", value)
op := &Operation{OperationType: TraversePath, Value: value, StringValue: value}
return &Token{TokenType: OperationToken, Operation: op, CheckForPostTraverse: true}, nil
}
}
func documentToken() lex.Action {
return func(s *lex.Scanner, m *machines.Match) (interface{}, error) {
var numberString = string(m.Bytes)
numberString = numberString[1:]
var number, errParsingInt = strconv.ParseInt(numberString, 10, 64) // nolint
if errParsingInt != nil {
return nil, errParsingInt
}
log.Debug("documentToken %v", string(m.Bytes))
op := &Operation{OperationType: DocumentFilter, Value: number, StringValue: numberString}
return &Token{TokenType: OperationToken, Operation: op, CheckForPostTraverse: true}, nil
}
}
func opToken(op *OperationType) lex.Action {
return opTokenWithPrefs(op, nil, nil)
}
func opAssignableToken(opType *OperationType, assignOpType *OperationType) lex.Action {
return opTokenWithPrefs(opType, assignOpType, nil)
}
func assignOpToken(updateAssign bool) lex.Action {
return func(s *lex.Scanner, m *machines.Match) (interface{}, error) {
log.Debug("assignOpToken %v", string(m.Bytes))
value := string(m.Bytes)
op := &Operation{OperationType: Assign, Value: Assign.Type, StringValue: value, UpdateAssign: updateAssign}
return &Token{TokenType: OperationToken, Operation: op}, nil
}
}
func opTokenWithPrefs(op *OperationType, assignOpType *OperationType, preferences interface{}) lex.Action {
return func(s *lex.Scanner, m *machines.Match) (interface{}, error) {
log.Debug("opTokenWithPrefs %v", string(m.Bytes))
value := string(m.Bytes)
op := &Operation{OperationType: op, Value: op.Type, StringValue: value, Preferences: preferences}
var assign *Operation
if assignOpType != nil {
assign = &Operation{OperationType: assignOpType, Value: assignOpType.Type, StringValue: value, Preferences: preferences}
}
return &Token{TokenType: OperationToken, Operation: op, AssignOperation: assign}, nil
}
}
func assignAllCommentsOp(updateAssign bool) lex.Action {
return func(s *lex.Scanner, m *machines.Match) (interface{}, error) {
log.Debug("assignAllCommentsOp %v", string(m.Bytes))
value := string(m.Bytes)
op := &Operation{
OperationType: AssignComment,
Value: AssignComment.Type,
StringValue: value,
UpdateAssign: updateAssign,
Preferences: &CommentOpPreferences{LineComment: true, HeadComment: true, FootComment: true},
}
return &Token{TokenType: OperationToken, Operation: op}, nil
}
}
func literalToken(pType TokenType, checkForPost bool) lex.Action {
return func(s *lex.Scanner, m *machines.Match) (interface{}, error) {
return &Token{TokenType: pType, CheckForPostTraverse: checkForPost}, nil
}
}
func unwrap(value string) string {
return value[1 : len(value)-1]
}
func numberValue() lex.Action {
return func(s *lex.Scanner, m *machines.Match) (interface{}, error) {
var numberString = string(m.Bytes)
var number, errParsingInt = strconv.ParseInt(numberString, 10, 64) // nolint
if errParsingInt != nil {
return nil, errParsingInt
}
return &Token{TokenType: OperationToken, Operation: CreateValueOperation(number, numberString)}, nil
}
}
func floatValue() lex.Action {
return func(s *lex.Scanner, m *machines.Match) (interface{}, error) {
var numberString = string(m.Bytes)
var number, errParsingInt = strconv.ParseFloat(numberString, 64) // nolint
if errParsingInt != nil {
return nil, errParsingInt
}
return &Token{TokenType: OperationToken, Operation: CreateValueOperation(number, numberString)}, nil
}
}
func booleanValue(val bool) lex.Action {
return func(s *lex.Scanner, m *machines.Match) (interface{}, error) {
return &Token{TokenType: OperationToken, Operation: CreateValueOperation(val, string(m.Bytes))}, nil
}
}
func stringValue(wrapped bool) lex.Action {
return func(s *lex.Scanner, m *machines.Match) (interface{}, error) {
value := string(m.Bytes)
if wrapped {
value = unwrap(value)
}
return &Token{TokenType: OperationToken, Operation: CreateValueOperation(value, value)}, nil
}
}
func envOp(strenv bool) lex.Action {
return func(s *lex.Scanner, m *machines.Match) (interface{}, error) {
value := string(m.Bytes)
if strenv {
// strenv( )
value = value[7:len(value)-1]
} else {
//env( )
value = value[4:len(value)-1]
}
envOperation := CreateValueOperation(value, value)
envOperation.OperationType = EnvOp
return &Token{TokenType: OperationToken, Operation: envOperation}, nil
}
}
func nullValue() lex.Action {
return func(s *lex.Scanner, m *machines.Match) (interface{}, error) {
return &Token{TokenType: OperationToken, Operation: CreateValueOperation(nil, string(m.Bytes))}, nil
}
}
func selfToken() lex.Action {
return func(s *lex.Scanner, m *machines.Match) (interface{}, error) {
op := &Operation{OperationType: SelfReference}
return &Token{TokenType: OperationToken, Operation: op}, nil
}
}
func initLexer() (*lex.Lexer, error) {
lexer := lex.NewLexer()
lexer.Add([]byte(`\(`), literalToken(OpenBracket, false))
lexer.Add([]byte(`\)`), literalToken(CloseBracket, true))
lexer.Add([]byte(`\.\[`), literalToken(TraverseArrayCollect, false))
lexer.Add([]byte(`\.\.`), opTokenWithPrefs(RecursiveDescent, nil, &RecursiveDescentPreferences{RecurseArray: true,
TraversePreferences: &TraversePreferences{FollowAlias: false, IncludeMapKeys: false}}))
lexer.Add([]byte(`\.\.\.`), opTokenWithPrefs(RecursiveDescent, nil, &RecursiveDescentPreferences{RecurseArray: true,
TraversePreferences: &TraversePreferences{FollowAlias: false, IncludeMapKeys: true}}))
lexer.Add([]byte(`,`), opToken(Union))
lexer.Add([]byte(`:\s*`), opToken(CreateMap))
lexer.Add([]byte(`length`), opToken(Length))
lexer.Add([]byte(`sortKeys`), opToken(SortKeys))
lexer.Add([]byte(`select`), opToken(Select))
lexer.Add([]byte(`has`), opToken(Has))
lexer.Add([]byte(`explode`), opToken(Explode))
lexer.Add([]byte(`or`), opToken(Or))
lexer.Add([]byte(`and`), opToken(And))
lexer.Add([]byte(`not`), opToken(Not))
lexer.Add([]byte(`\/\/`), opToken(Alternative))
lexer.Add([]byte(`documentIndex`), opToken(GetDocumentIndex))
lexer.Add([]byte(`di`), opToken(GetDocumentIndex))
lexer.Add([]byte(`style`), opAssignableToken(GetStyle, AssignStyle))
lexer.Add([]byte(`tag`), opAssignableToken(GetTag, AssignTag))
lexer.Add([]byte(`anchor`), opAssignableToken(GetAnchor, AssignAnchor))
lexer.Add([]byte(`alias`), opAssignableToken(GetAlias, AssignAlias))
lexer.Add([]byte(`filename`), opToken(GetFilename))
lexer.Add([]byte(`fileIndex`), opToken(GetFileIndex))
lexer.Add([]byte(`fi`), opToken(GetFileIndex))
lexer.Add([]byte(`path`), opToken(GetPath))
lexer.Add([]byte(`lineComment`), opTokenWithPrefs(GetComment, AssignComment, &CommentOpPreferences{LineComment: true}))
lexer.Add([]byte(`headComment`), opTokenWithPrefs(GetComment, AssignComment, &CommentOpPreferences{HeadComment: true}))
lexer.Add([]byte(`footComment`), opTokenWithPrefs(GetComment, AssignComment, &CommentOpPreferences{FootComment: true}))
lexer.Add([]byte(`comments\s*=`), assignAllCommentsOp(false))
lexer.Add([]byte(`comments\s*\|=`), assignAllCommentsOp(true))
lexer.Add([]byte(`collect`), opToken(Collect))
lexer.Add([]byte(`\s*==\s*`), opToken(Equals))
lexer.Add([]byte(`\s*=\s*`), assignOpToken(false))
lexer.Add([]byte(`del`), opToken(DeleteChild))
lexer.Add([]byte(`\s*\|=\s*`), assignOpToken(true))
lexer.Add([]byte("( |\t|\n|\r)+"), skip)
lexer.Add([]byte(`d[0-9]+`), documentToken())
lexer.Add([]byte(`\."[^ "]+"`), pathToken(true))
lexer.Add([]byte(`\.[^ \}\{\:\[\],\|\.\[\(\)=]+`), pathToken(false))
lexer.Add([]byte(`\.`), selfToken())
lexer.Add([]byte(`\|`), opToken(Pipe))
lexer.Add([]byte(`-?\d+(\.\d+)`), floatValue())
lexer.Add([]byte(`-?[1-9](\.\d+)?[Ee][-+]?\d+`), floatValue())
lexer.Add([]byte(`-?\d+`), numberValue())
lexer.Add([]byte(`[Tt][Rr][Uu][Ee]`), booleanValue(true))
lexer.Add([]byte(`[Ff][Aa][Ll][Ss][Ee]`), booleanValue(false))
lexer.Add([]byte(`[Nn][Uu][Ll][Ll]`), nullValue())
lexer.Add([]byte(`~`), nullValue())
lexer.Add([]byte(`"[^"]*"`), stringValue(true))
lexer.Add([]byte(`strenv\([^\)]+\)`), envOp(true))
lexer.Add([]byte(`\[`), literalToken(OpenCollect, false))
lexer.Add([]byte(`\]`), literalToken(CloseCollect, true))
lexer.Add([]byte(`\{`), literalToken(OpenCollectObject, false))
lexer.Add([]byte(`\}`), literalToken(CloseCollectObject, true))
lexer.Add([]byte(`\*`), opTokenWithPrefs(Multiply, nil, &MultiplyPreferences{AppendArrays: false}))
lexer.Add([]byte(`\*\+`), opTokenWithPrefs(Multiply, nil, &MultiplyPreferences{AppendArrays: true}))
lexer.Add([]byte(`\+`), opToken(Add))
lexer.Add([]byte(`\+=`), opToken(AddAssign))
err := lexer.Compile()
if err != nil {
return nil, err
}
return lexer, nil
}
type PathTokeniser interface {
Tokenise(path string) ([]*Token, error)
}
type pathTokeniser struct {
lexer *lex.Lexer
}
func NewPathTokeniser() PathTokeniser {
var lexer, err = initLexer()
if err != nil {
panic(err)
}
return &pathTokeniser{lexer}
}
func (p *pathTokeniser) Tokenise(path string) ([]*Token, error) {
scanner, err := p.lexer.Scanner([]byte(path))
if err != nil {
return nil, fmt.Errorf("Parsing expression: %v", err)
}
var tokens []*Token
for tok, err, eof := scanner.Next(); !eof; tok, err, eof = scanner.Next() {
if tok != nil {
token := tok.(*Token)
log.Debugf("Tokenising %v", token.toString())
tokens = append(tokens, token)
}
if err != nil {
return nil, fmt.Errorf("Parsing expression: %v", err)
}
}
var postProcessedTokens = make([]*Token, 0)
skipNextToken := false
for index := range tokens {
if skipNextToken {
skipNextToken = false
} else {
postProcessedTokens, skipNextToken = p.handleToken(tokens, index, postProcessedTokens)
}
}
return postProcessedTokens, nil
}
func (p *pathTokeniser) handleToken(tokens []*Token, index int, postProcessedTokens []*Token) (tokensAccum []*Token, skipNextToken bool) {
skipNextToken = false
token := tokens[index]
if token.TokenType == TraverseArrayCollect {
//need to put a traverse array then a collect token
// do this by adding traverse then converting token to collect
op := &Operation{OperationType: TraverseArray, StringValue: "TRAVERSE_ARRAY"}
postProcessedTokens = append(postProcessedTokens, &Token{TokenType: OperationToken, Operation: op})
token = &Token{TokenType: OpenCollect}
}
if index != len(tokens)-1 && token.AssignOperation != nil &&
tokens[index+1].TokenType == OperationToken &&
tokens[index+1].Operation.OperationType == Assign {
token.Operation = token.AssignOperation
token.Operation.UpdateAssign = tokens[index+1].Operation.UpdateAssign
skipNextToken = true
}
postProcessedTokens = append(postProcessedTokens, token)
if index != len(tokens)-1 && token.CheckForPostTraverse &&
tokens[index+1].TokenType == OperationToken &&
tokens[index+1].Operation.OperationType == TraversePath {
op := &Operation{OperationType: ShortPipe, Value: "PIPE"}
postProcessedTokens = append(postProcessedTokens, &Token{TokenType: OperationToken, Operation: op})
}
if index != len(tokens)-1 && token.CheckForPostTraverse &&
tokens[index+1].TokenType == OpenCollect {
op := &Operation{OperationType: ShortPipe, Value: "PIPE"}
postProcessedTokens = append(postProcessedTokens, &Token{TokenType: OperationToken, Operation: op})
op = &Operation{OperationType: TraverseArray}
postProcessedTokens = append(postProcessedTokens, &Token{TokenType: OperationToken, Operation: op})
}
if index != len(tokens)-1 && token.CheckForPostTraverse &&
tokens[index+1].TokenType == TraverseArrayCollect {
op := &Operation{OperationType: ShortPipe, Value: "PIPE"}
postProcessedTokens = append(postProcessedTokens, &Token{TokenType: OperationToken, Operation: op})
}
return postProcessedTokens, skipNextToken
}