diff options
Diffstat (limited to 'vendor/github.com/jmespath/go-jmespath/parser.go')
| -rw-r--r-- | vendor/github.com/jmespath/go-jmespath/parser.go | 603 |
1 files changed, 0 insertions, 603 deletions
diff --git a/vendor/github.com/jmespath/go-jmespath/parser.go b/vendor/github.com/jmespath/go-jmespath/parser.go deleted file mode 100644 index 1240a17..0000000 --- a/vendor/github.com/jmespath/go-jmespath/parser.go +++ /dev/null @@ -1,603 +0,0 @@ -package jmespath - -import ( - "encoding/json" - "fmt" - "strconv" - "strings" -) - -type astNodeType int - -//go:generate stringer -type astNodeType -const ( - ASTEmpty astNodeType = iota - ASTComparator - ASTCurrentNode - ASTExpRef - ASTFunctionExpression - ASTField - ASTFilterProjection - ASTFlatten - ASTIdentity - ASTIndex - ASTIndexExpression - ASTKeyValPair - ASTLiteral - ASTMultiSelectHash - ASTMultiSelectList - ASTOrExpression - ASTAndExpression - ASTNotExpression - ASTPipe - ASTProjection - ASTSubexpression - ASTSlice - ASTValueProjection -) - -// ASTNode represents the abstract syntax tree of a JMESPath expression. -type ASTNode struct { - nodeType astNodeType - value interface{} - children []ASTNode -} - -func (node ASTNode) String() string { - return node.PrettyPrint(0) -} - -// PrettyPrint will pretty print the parsed AST. -// The AST is an implementation detail and this pretty print -// function is provided as a convenience method to help with -// debugging. You should not rely on its output as the internal -// structure of the AST may change at any time. -func (node ASTNode) PrettyPrint(indent int) string { - spaces := strings.Repeat(" ", indent) - output := fmt.Sprintf("%s%s {\n", spaces, node.nodeType) - nextIndent := indent + 2 - if node.value != nil { - if converted, ok := node.value.(fmt.Stringer); ok { - // Account for things like comparator nodes - // that are enums with a String() method. - output += fmt.Sprintf("%svalue: %s\n", strings.Repeat(" ", nextIndent), converted.String()) - } else { - output += fmt.Sprintf("%svalue: %#v\n", strings.Repeat(" ", nextIndent), node.value) - } - } - lastIndex := len(node.children) - if lastIndex > 0 { - output += fmt.Sprintf("%schildren: {\n", strings.Repeat(" ", nextIndent)) - childIndent := nextIndent + 2 - for _, elem := range node.children { - output += elem.PrettyPrint(childIndent) - } - } - output += fmt.Sprintf("%s}\n", spaces) - return output -} - -var bindingPowers = map[tokType]int{ - tEOF: 0, - tUnquotedIdentifier: 0, - tQuotedIdentifier: 0, - tRbracket: 0, - tRparen: 0, - tComma: 0, - tRbrace: 0, - tNumber: 0, - tCurrent: 0, - tExpref: 0, - tColon: 0, - tPipe: 1, - tOr: 2, - tAnd: 3, - tEQ: 5, - tLT: 5, - tLTE: 5, - tGT: 5, - tGTE: 5, - tNE: 5, - tFlatten: 9, - tStar: 20, - tFilter: 21, - tDot: 40, - tNot: 45, - tLbrace: 50, - tLbracket: 55, - tLparen: 60, -} - -// Parser holds state about the current expression being parsed. -type Parser struct { - expression string - tokens []token - index int -} - -// NewParser creates a new JMESPath parser. -func NewParser() *Parser { - p := Parser{} - return &p -} - -// Parse will compile a JMESPath expression. -func (p *Parser) Parse(expression string) (ASTNode, error) { - lexer := NewLexer() - p.expression = expression - p.index = 0 - tokens, err := lexer.tokenize(expression) - if err != nil { - return ASTNode{}, err - } - p.tokens = tokens - parsed, err := p.parseExpression(0) - if err != nil { - return ASTNode{}, err - } - if p.current() != tEOF { - return ASTNode{}, p.syntaxError(fmt.Sprintf( - "Unexpected token at the end of the expresssion: %s", p.current())) - } - return parsed, nil -} - -func (p *Parser) parseExpression(bindingPower int) (ASTNode, error) { - var err error - leftToken := p.lookaheadToken(0) - p.advance() - leftNode, err := p.nud(leftToken) - if err != nil { - return ASTNode{}, err - } - currentToken := p.current() - for bindingPower < bindingPowers[currentToken] { - p.advance() - leftNode, err = p.led(currentToken, leftNode) - if err != nil { - return ASTNode{}, err - } - currentToken = p.current() - } - return leftNode, nil -} - -func (p *Parser) parseIndexExpression() (ASTNode, error) { - if p.lookahead(0) == tColon || p.lookahead(1) == tColon { - return p.parseSliceExpression() - } - indexStr := p.lookaheadToken(0).value - parsedInt, err := strconv.Atoi(indexStr) - if err != nil { - return ASTNode{}, err - } - indexNode := ASTNode{nodeType: ASTIndex, value: parsedInt} - p.advance() - if err := p.match(tRbracket); err != nil { - return ASTNode{}, err - } - return indexNode, nil -} - -func (p *Parser) parseSliceExpression() (ASTNode, error) { - parts := []*int{nil, nil, nil} - index := 0 - current := p.current() - for current != tRbracket && index < 3 { - if current == tColon { - index++ - p.advance() - } else if current == tNumber { - parsedInt, err := strconv.Atoi(p.lookaheadToken(0).value) - if err != nil { - return ASTNode{}, err - } - parts[index] = &parsedInt - p.advance() - } else { - return ASTNode{}, p.syntaxError( - "Expected tColon or tNumber" + ", received: " + p.current().String()) - } - current = p.current() - } - if err := p.match(tRbracket); err != nil { - return ASTNode{}, err - } - return ASTNode{ - nodeType: ASTSlice, - value: parts, - }, nil -} - -func (p *Parser) match(tokenType tokType) error { - if p.current() == tokenType { - p.advance() - return nil - } - return p.syntaxError("Expected " + tokenType.String() + ", received: " + p.current().String()) -} - -func (p *Parser) led(tokenType tokType, node ASTNode) (ASTNode, error) { - switch tokenType { - case tDot: - if p.current() != tStar { - right, err := p.parseDotRHS(bindingPowers[tDot]) - return ASTNode{ - nodeType: ASTSubexpression, - children: []ASTNode{node, right}, - }, err - } - p.advance() - right, err := p.parseProjectionRHS(bindingPowers[tDot]) - return ASTNode{ - nodeType: ASTValueProjection, - children: []ASTNode{node, right}, - }, err - case tPipe: - right, err := p.parseExpression(bindingPowers[tPipe]) - return ASTNode{nodeType: ASTPipe, children: []ASTNode{node, right}}, err - case tOr: - right, err := p.parseExpression(bindingPowers[tOr]) - return ASTNode{nodeType: ASTOrExpression, children: []ASTNode{node, right}}, err - case tAnd: - right, err := p.parseExpression(bindingPowers[tAnd]) - return ASTNode{nodeType: ASTAndExpression, children: []ASTNode{node, right}}, err - case tLparen: - name := node.value - var args []ASTNode - for p.current() != tRparen { - expression, err := p.parseExpression(0) - if err != nil { - return ASTNode{}, err - } - if p.current() == tComma { - if err := p.match(tComma); err != nil { - return ASTNode{}, err - } - } - args = append(args, expression) - } - if err := p.match(tRparen); err != nil { - return ASTNode{}, err - } - return ASTNode{ - nodeType: ASTFunctionExpression, - value: name, - children: args, - }, nil - case tFilter: - return p.parseFilter(node) - case tFlatten: - left := ASTNode{nodeType: ASTFlatten, children: []ASTNode{node}} - right, err := p.parseProjectionRHS(bindingPowers[tFlatten]) - return ASTNode{ - nodeType: ASTProjection, - children: []ASTNode{left, right}, - }, err - case tEQ, tNE, tGT, tGTE, tLT, tLTE: - right, err := p.parseExpression(bindingPowers[tokenType]) - if err != nil { - return ASTNode{}, err - } - return ASTNode{ - nodeType: ASTComparator, - value: tokenType, - children: []ASTNode{node, right}, - }, nil - case tLbracket: - tokenType := p.current() - var right ASTNode - var err error - if tokenType == tNumber || tokenType == tColon { - right, err = p.parseIndexExpression() - if err != nil { - return ASTNode{}, err - } - return p.projectIfSlice(node, right) - } - // Otherwise this is a projection. - if err := p.match(tStar); err != nil { - return ASTNode{}, err - } - if err := p.match(tRbracket); err != nil { - return ASTNode{}, err - } - right, err = p.parseProjectionRHS(bindingPowers[tStar]) - if err != nil { - return ASTNode{}, err - } - return ASTNode{ - nodeType: ASTProjection, - children: []ASTNode{node, right}, - }, nil - } - return ASTNode{}, p.syntaxError("Unexpected token: " + tokenType.String()) -} - -func (p *Parser) nud(token token) (ASTNode, error) { - switch token.tokenType { - case tJSONLiteral: - var parsed interface{} - err := json.Unmarshal([]byte(token.value), &parsed) - if err != nil { - return ASTNode{}, err - } - return ASTNode{nodeType: ASTLiteral, value: parsed}, nil - case tStringLiteral: - return ASTNode{nodeType: ASTLiteral, value: token.value}, nil - case tUnquotedIdentifier: - return ASTNode{ - nodeType: ASTField, - value: token.value, - }, nil - case tQuotedIdentifier: - node := ASTNode{nodeType: ASTField, value: token.value} - if p.current() == tLparen { - return ASTNode{}, p.syntaxErrorToken("Can't have quoted identifier as function name.", token) - } - return node, nil - case tStar: - left := ASTNode{nodeType: ASTIdentity} - var right ASTNode - var err error - if p.current() == tRbracket { - right = ASTNode{nodeType: ASTIdentity} - } else { - right, err = p.parseProjectionRHS(bindingPowers[tStar]) - } - return ASTNode{nodeType: ASTValueProjection, children: []ASTNode{left, right}}, err - case tFilter: - return p.parseFilter(ASTNode{nodeType: ASTIdentity}) - case tLbrace: - return p.parseMultiSelectHash() - case tFlatten: - left := ASTNode{ - nodeType: ASTFlatten, - children: []ASTNode{{nodeType: ASTIdentity}}, - } - right, err := p.parseProjectionRHS(bindingPowers[tFlatten]) - if err != nil { - return ASTNode{}, err - } - return ASTNode{nodeType: ASTProjection, children: []ASTNode{left, right}}, nil - case tLbracket: - tokenType := p.current() - //var right ASTNode - if tokenType == tNumber || tokenType == tColon { - right, err := p.parseIndexExpression() - if err != nil { - return ASTNode{}, nil - } - return p.projectIfSlice(ASTNode{nodeType: ASTIdentity}, right) - } else if tokenType == tStar && p.lookahead(1) == tRbracket { - p.advance() - p.advance() - right, err := p.parseProjectionRHS(bindingPowers[tStar]) - if err != nil { - return ASTNode{}, err - } - return ASTNode{ - nodeType: ASTProjection, - children: []ASTNode{{nodeType: ASTIdentity}, right}, - }, nil - } else { - return p.parseMultiSelectList() - } - case tCurrent: - return ASTNode{nodeType: ASTCurrentNode}, nil - case tExpref: - expression, err := p.parseExpression(bindingPowers[tExpref]) - if err != nil { - return ASTNode{}, err - } - return ASTNode{nodeType: ASTExpRef, children: []ASTNode{expression}}, nil - case tNot: - expression, err := p.parseExpression(bindingPowers[tNot]) - if err != nil { - return ASTNode{}, err - } - return ASTNode{nodeType: ASTNotExpression, children: []ASTNode{expression}}, nil - case tLparen: - expression, err := p.parseExpression(0) - if err != nil { - return ASTNode{}, err - } - if err := p.match(tRparen); err != nil { - return ASTNode{}, err - } - return expression, nil - case tEOF: - return ASTNode{}, p.syntaxErrorToken("Incomplete expression", token) - } - - return ASTNode{}, p.syntaxErrorToken("Invalid token: "+token.tokenType.String(), token) -} - -func (p *Parser) parseMultiSelectList() (ASTNode, error) { - var expressions []ASTNode - for { - expression, err := p.parseExpression(0) - if err != nil { - return ASTNode{}, err - } - expressions = append(expressions, expression) - if p.current() == tRbracket { - break - } - err = p.match(tComma) - if err != nil { - return ASTNode{}, err - } - } - err := p.match(tRbracket) - if err != nil { - return ASTNode{}, err - } - return ASTNode{ - nodeType: ASTMultiSelectList, - children: expressions, - }, nil -} - -func (p *Parser) parseMultiSelectHash() (ASTNode, error) { - var children []ASTNode - for { - keyToken := p.lookaheadToken(0) - if err := p.match(tUnquotedIdentifier); err != nil { - if err := p.match(tQuotedIdentifier); err != nil { - return ASTNode{}, p.syntaxError("Expected tQuotedIdentifier or tUnquotedIdentifier") - } - } - keyName := keyToken.value - err := p.match(tColon) - if err != nil { - return ASTNode{}, err - } - value, err := p.parseExpression(0) - if err != nil { - return ASTNode{}, err - } - node := ASTNode{ - nodeType: ASTKeyValPair, - value: keyName, - children: []ASTNode{value}, - } - children = append(children, node) - if p.current() == tComma { - err := p.match(tComma) - if err != nil { - return ASTNode{}, nil - } - } else if p.current() == tRbrace { - err := p.match(tRbrace) - if err != nil { - return ASTNode{}, nil - } - break - } - } - return ASTNode{ - nodeType: ASTMultiSelectHash, - children: children, - }, nil -} - -func (p *Parser) projectIfSlice(left ASTNode, right ASTNode) (ASTNode, error) { - indexExpr := ASTNode{ - nodeType: ASTIndexExpression, - children: []ASTNode{left, right}, - } - if right.nodeType == ASTSlice { - right, err := p.parseProjectionRHS(bindingPowers[tStar]) - return ASTNode{ - nodeType: ASTProjection, - children: []ASTNode{indexExpr, right}, - }, err - } - return indexExpr, nil -} -func (p *Parser) parseFilter(node ASTNode) (ASTNode, error) { - var right, condition ASTNode - var err error - condition, err = p.parseExpression(0) - if err != nil { - return ASTNode{}, err - } - if err := p.match(tRbracket); err != nil { - return ASTNode{}, err - } - if p.current() == tFlatten { - right = ASTNode{nodeType: ASTIdentity} - } else { - right, err = p.parseProjectionRHS(bindingPowers[tFilter]) - if err != nil { - return ASTNode{}, err - } - } - - return ASTNode{ - nodeType: ASTFilterProjection, - children: []ASTNode{node, right, condition}, - }, nil -} - -func (p *Parser) parseDotRHS(bindingPower int) (ASTNode, error) { - lookahead := p.current() - if tokensOneOf([]tokType{tQuotedIdentifier, tUnquotedIdentifier, tStar}, lookahead) { - return p.parseExpression(bindingPower) - } else if lookahead == tLbracket { - if err := p.match(tLbracket); err != nil { - return ASTNode{}, err - } - return p.parseMultiSelectList() - } else if lookahead == tLbrace { - if err := p.match(tLbrace); err != nil { - return ASTNode{}, err - } - return p.parseMultiSelectHash() - } - return ASTNode{}, p.syntaxError("Expected identifier, lbracket, or lbrace") -} - -func (p *Parser) parseProjectionRHS(bindingPower int) (ASTNode, error) { - current := p.current() - if bindingPowers[current] < 10 { - return ASTNode{nodeType: ASTIdentity}, nil - } else if current == tLbracket { - return p.parseExpression(bindingPower) - } else if current == tFilter { - return p.parseExpression(bindingPower) - } else if current == tDot { - err := p.match(tDot) - if err != nil { - return ASTNode{}, err - } - return p.parseDotRHS(bindingPower) - } else { - return ASTNode{}, p.syntaxError("Error") - } -} - -func (p *Parser) lookahead(number int) tokType { - return p.lookaheadToken(number).tokenType -} - -func (p *Parser) current() tokType { - return p.lookahead(0) -} - -func (p *Parser) lookaheadToken(number int) token { - return p.tokens[p.index+number] -} - -func (p *Parser) advance() { - p.index++ -} - -func tokensOneOf(elements []tokType, token tokType) bool { - for _, elem := range elements { - if elem == token { - return true - } - } - return false -} - -func (p *Parser) syntaxError(msg string) SyntaxError { - return SyntaxError{ - msg: msg, - Expression: p.expression, - Offset: p.lookaheadToken(0).position, - } -} - -// Create a SyntaxError based on the provided token. -// This differs from syntaxError() which creates a SyntaxError -// based on the current lookahead token. -func (p *Parser) syntaxErrorToken(msg string, t token) SyntaxError { - return SyntaxError{ - msg: msg, - Expression: p.expression, - Offset: t.position, - } -} |