diff options
Diffstat (limited to 'vendor/k8s.io/apimachinery/pkg/labels/selector.go')
| -rw-r--r-- | vendor/k8s.io/apimachinery/pkg/labels/selector.go | 956 |
1 files changed, 0 insertions, 956 deletions
diff --git a/vendor/k8s.io/apimachinery/pkg/labels/selector.go b/vendor/k8s.io/apimachinery/pkg/labels/selector.go deleted file mode 100644 index 9eea34579..000000000 --- a/vendor/k8s.io/apimachinery/pkg/labels/selector.go +++ /dev/null @@ -1,956 +0,0 @@ -/* -Copyright 2014 The Kubernetes Authors. - -Licensed under the Apache License, Version 2.0 (the "License"); -you may not use this file except in compliance with the License. -You may obtain a copy of the License at - - http://www.apache.org/licenses/LICENSE-2.0 - -Unless required by applicable law or agreed to in writing, software -distributed under the License is distributed on an "AS IS" BASIS, -WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -See the License for the specific language governing permissions and -limitations under the License. -*/ - -package labels - -import ( - "fmt" - "sort" - "strconv" - "strings" - - "github.com/google/go-cmp/cmp" - "k8s.io/apimachinery/pkg/selection" - "k8s.io/apimachinery/pkg/util/sets" - "k8s.io/apimachinery/pkg/util/validation" - "k8s.io/apimachinery/pkg/util/validation/field" - "k8s.io/klog/v2" -) - -var ( - unaryOperators = []string{ - string(selection.Exists), string(selection.DoesNotExist), - } - binaryOperators = []string{ - string(selection.In), string(selection.NotIn), - string(selection.Equals), string(selection.DoubleEquals), string(selection.NotEquals), - string(selection.GreaterThan), string(selection.LessThan), - } - validRequirementOperators = append(binaryOperators, unaryOperators...) -) - -// Requirements is AND of all requirements. -type Requirements []Requirement - -// Selector represents a label selector. -type Selector interface { - // Matches returns true if this selector matches the given set of labels. - Matches(Labels) bool - - // Empty returns true if this selector does not restrict the selection space. - Empty() bool - - // String returns a human readable string that represents this selector. - String() string - - // Add adds requirements to the Selector - Add(r ...Requirement) Selector - - // Requirements converts this interface into Requirements to expose - // more detailed selection information. - // If there are querying parameters, it will return converted requirements and selectable=true. - // If this selector doesn't want to select anything, it will return selectable=false. - Requirements() (requirements Requirements, selectable bool) - - // Make a deep copy of the selector. - DeepCopySelector() Selector - - // RequiresExactMatch allows a caller to introspect whether a given selector - // requires a single specific label to be set, and if so returns the value it - // requires. - RequiresExactMatch(label string) (value string, found bool) -} - -// Everything returns a selector that matches all labels. -func Everything() Selector { - return internalSelector{} -} - -type nothingSelector struct{} - -func (n nothingSelector) Matches(_ Labels) bool { return false } -func (n nothingSelector) Empty() bool { return false } -func (n nothingSelector) String() string { return "" } -func (n nothingSelector) Add(_ ...Requirement) Selector { return n } -func (n nothingSelector) Requirements() (Requirements, bool) { return nil, false } -func (n nothingSelector) DeepCopySelector() Selector { return n } -func (n nothingSelector) RequiresExactMatch(label string) (value string, found bool) { - return "", false -} - -// Nothing returns a selector that matches no labels -func Nothing() Selector { - return nothingSelector{} -} - -// NewSelector returns a nil selector -func NewSelector() Selector { - return internalSelector(nil) -} - -type internalSelector []Requirement - -func (s internalSelector) DeepCopy() internalSelector { - if s == nil { - return nil - } - result := make([]Requirement, len(s)) - for i := range s { - s[i].DeepCopyInto(&result[i]) - } - return result -} - -func (s internalSelector) DeepCopySelector() Selector { - return s.DeepCopy() -} - -// ByKey sorts requirements by key to obtain deterministic parser -type ByKey []Requirement - -func (a ByKey) Len() int { return len(a) } - -func (a ByKey) Swap(i, j int) { a[i], a[j] = a[j], a[i] } - -func (a ByKey) Less(i, j int) bool { return a[i].key < a[j].key } - -// Requirement contains values, a key, and an operator that relates the key and values. -// The zero value of Requirement is invalid. -// Requirement implements both set based match and exact match -// Requirement should be initialized via NewRequirement constructor for creating a valid Requirement. -// +k8s:deepcopy-gen=true -type Requirement struct { - key string - operator selection.Operator - // In huge majority of cases we have at most one value here. - // It is generally faster to operate on a single-element slice - // than on a single-element map, so we have a slice here. - strValues []string -} - -// NewRequirement is the constructor for a Requirement. -// If any of these rules is violated, an error is returned: -// (1) The operator can only be In, NotIn, Equals, DoubleEquals, Gt, Lt, NotEquals, Exists, or DoesNotExist. -// (2) If the operator is In or NotIn, the values set must be non-empty. -// (3) If the operator is Equals, DoubleEquals, or NotEquals, the values set must contain one value. -// (4) If the operator is Exists or DoesNotExist, the value set must be empty. -// (5) If the operator is Gt or Lt, the values set must contain only one value, which will be interpreted as an integer. -// (6) The key is invalid due to its length, or sequence -// of characters. See validateLabelKey for more details. -// -// The empty string is a valid value in the input values set. -// Returned error, if not nil, is guaranteed to be an aggregated field.ErrorList -func NewRequirement(key string, op selection.Operator, vals []string, opts ...field.PathOption) (*Requirement, error) { - var allErrs field.ErrorList - path := field.ToPath(opts...) - if err := validateLabelKey(key, path.Child("key")); err != nil { - allErrs = append(allErrs, err) - } - - valuePath := path.Child("values") - switch op { - case selection.In, selection.NotIn: - if len(vals) == 0 { - allErrs = append(allErrs, field.Invalid(valuePath, vals, "for 'in', 'notin' operators, values set can't be empty")) - } - case selection.Equals, selection.DoubleEquals, selection.NotEquals: - if len(vals) != 1 { - allErrs = append(allErrs, field.Invalid(valuePath, vals, "exact-match compatibility requires one single value")) - } - case selection.Exists, selection.DoesNotExist: - if len(vals) != 0 { - allErrs = append(allErrs, field.Invalid(valuePath, vals, "values set must be empty for exists and does not exist")) - } - case selection.GreaterThan, selection.LessThan: - if len(vals) != 1 { - allErrs = append(allErrs, field.Invalid(valuePath, vals, "for 'Gt', 'Lt' operators, exactly one value is required")) - } - for i := range vals { - if _, err := strconv.ParseInt(vals[i], 10, 64); err != nil { - allErrs = append(allErrs, field.Invalid(valuePath.Index(i), vals[i], "for 'Gt', 'Lt' operators, the value must be an integer")) - } - } - default: - allErrs = append(allErrs, field.NotSupported(path.Child("operator"), op, validRequirementOperators)) - } - - for i := range vals { - if err := validateLabelValue(key, vals[i], valuePath.Index(i)); err != nil { - allErrs = append(allErrs, err) - } - } - return &Requirement{key: key, operator: op, strValues: vals}, allErrs.ToAggregate() -} - -func (r *Requirement) hasValue(value string) bool { - for i := range r.strValues { - if r.strValues[i] == value { - return true - } - } - return false -} - -// Matches returns true if the Requirement matches the input Labels. -// There is a match in the following cases: -// (1) The operator is Exists and Labels has the Requirement's key. -// (2) The operator is In, Labels has the Requirement's key and Labels' -// value for that key is in Requirement's value set. -// (3) The operator is NotIn, Labels has the Requirement's key and -// Labels' value for that key is not in Requirement's value set. -// (4) The operator is DoesNotExist or NotIn and Labels does not have the -// Requirement's key. -// (5) The operator is GreaterThanOperator or LessThanOperator, and Labels has -// the Requirement's key and the corresponding value satisfies mathematical inequality. -func (r *Requirement) Matches(ls Labels) bool { - switch r.operator { - case selection.In, selection.Equals, selection.DoubleEquals: - if !ls.Has(r.key) { - return false - } - return r.hasValue(ls.Get(r.key)) - case selection.NotIn, selection.NotEquals: - if !ls.Has(r.key) { - return true - } - return !r.hasValue(ls.Get(r.key)) - case selection.Exists: - return ls.Has(r.key) - case selection.DoesNotExist: - return !ls.Has(r.key) - case selection.GreaterThan, selection.LessThan: - if !ls.Has(r.key) { - return false - } - lsValue, err := strconv.ParseInt(ls.Get(r.key), 10, 64) - if err != nil { - klog.V(10).Infof("ParseInt failed for value %+v in label %+v, %+v", ls.Get(r.key), ls, err) - return false - } - - // There should be only one strValue in r.strValues, and can be converted to an integer. - if len(r.strValues) != 1 { - klog.V(10).Infof("Invalid values count %+v of requirement %#v, for 'Gt', 'Lt' operators, exactly one value is required", len(r.strValues), r) - return false - } - - var rValue int64 - for i := range r.strValues { - rValue, err = strconv.ParseInt(r.strValues[i], 10, 64) - if err != nil { - klog.V(10).Infof("ParseInt failed for value %+v in requirement %#v, for 'Gt', 'Lt' operators, the value must be an integer", r.strValues[i], r) - return false - } - } - return (r.operator == selection.GreaterThan && lsValue > rValue) || (r.operator == selection.LessThan && lsValue < rValue) - default: - return false - } -} - -// Key returns requirement key -func (r *Requirement) Key() string { - return r.key -} - -// Operator returns requirement operator -func (r *Requirement) Operator() selection.Operator { - return r.operator -} - -// Values returns requirement values -func (r *Requirement) Values() sets.String { - ret := sets.String{} - for i := range r.strValues { - ret.Insert(r.strValues[i]) - } - return ret -} - -// Equal checks the equality of requirement. -func (r Requirement) Equal(x Requirement) bool { - if r.key != x.key { - return false - } - if r.operator != x.operator { - return false - } - return cmp.Equal(r.strValues, x.strValues) -} - -// Empty returns true if the internalSelector doesn't restrict selection space -func (s internalSelector) Empty() bool { - if s == nil { - return true - } - return len(s) == 0 -} - -// String returns a human-readable string that represents this -// Requirement. If called on an invalid Requirement, an error is -// returned. See NewRequirement for creating a valid Requirement. -func (r *Requirement) String() string { - var sb strings.Builder - sb.Grow( - // length of r.key - len(r.key) + - // length of 'r.operator' + 2 spaces for the worst case ('in' and 'notin') - len(r.operator) + 2 + - // length of 'r.strValues' slice times. Heuristically 5 chars per word - +5*len(r.strValues)) - if r.operator == selection.DoesNotExist { - sb.WriteString("!") - } - sb.WriteString(r.key) - - switch r.operator { - case selection.Equals: - sb.WriteString("=") - case selection.DoubleEquals: - sb.WriteString("==") - case selection.NotEquals: - sb.WriteString("!=") - case selection.In: - sb.WriteString(" in ") - case selection.NotIn: - sb.WriteString(" notin ") - case selection.GreaterThan: - sb.WriteString(">") - case selection.LessThan: - sb.WriteString("<") - case selection.Exists, selection.DoesNotExist: - return sb.String() - } - - switch r.operator { - case selection.In, selection.NotIn: - sb.WriteString("(") - } - if len(r.strValues) == 1 { - sb.WriteString(r.strValues[0]) - } else { // only > 1 since == 0 prohibited by NewRequirement - // normalizes value order on output, without mutating the in-memory selector representation - // also avoids normalization when it is not required, and ensures we do not mutate shared data - sb.WriteString(strings.Join(safeSort(r.strValues), ",")) - } - - switch r.operator { - case selection.In, selection.NotIn: - sb.WriteString(")") - } - return sb.String() -} - -// safeSort sorts input strings without modification -func safeSort(in []string) []string { - if sort.StringsAreSorted(in) { - return in - } - out := make([]string, len(in)) - copy(out, in) - sort.Strings(out) - return out -} - -// Add adds requirements to the selector. It copies the current selector returning a new one -func (s internalSelector) Add(reqs ...Requirement) Selector { - ret := make(internalSelector, 0, len(s)+len(reqs)) - ret = append(ret, s...) - ret = append(ret, reqs...) - sort.Sort(ByKey(ret)) - return ret -} - -// Matches for a internalSelector returns true if all -// its Requirements match the input Labels. If any -// Requirement does not match, false is returned. -func (s internalSelector) Matches(l Labels) bool { - for ix := range s { - if matches := s[ix].Matches(l); !matches { - return false - } - } - return true -} - -func (s internalSelector) Requirements() (Requirements, bool) { return Requirements(s), true } - -// String returns a comma-separated string of all -// the internalSelector Requirements' human-readable strings. -func (s internalSelector) String() string { - var reqs []string - for ix := range s { - reqs = append(reqs, s[ix].String()) - } - return strings.Join(reqs, ",") -} - -// RequiresExactMatch introspects whether a given selector requires a single specific field -// to be set, and if so returns the value it requires. -func (s internalSelector) RequiresExactMatch(label string) (value string, found bool) { - for ix := range s { - if s[ix].key == label { - switch s[ix].operator { - case selection.Equals, selection.DoubleEquals, selection.In: - if len(s[ix].strValues) == 1 { - return s[ix].strValues[0], true - } - } - return "", false - } - } - return "", false -} - -// Token represents constant definition for lexer token -type Token int - -const ( - // ErrorToken represents scan error - ErrorToken Token = iota - // EndOfStringToken represents end of string - EndOfStringToken - // ClosedParToken represents close parenthesis - ClosedParToken - // CommaToken represents the comma - CommaToken - // DoesNotExistToken represents logic not - DoesNotExistToken - // DoubleEqualsToken represents double equals - DoubleEqualsToken - // EqualsToken represents equal - EqualsToken - // GreaterThanToken represents greater than - GreaterThanToken - // IdentifierToken represents identifier, e.g. keys and values - IdentifierToken - // InToken represents in - InToken - // LessThanToken represents less than - LessThanToken - // NotEqualsToken represents not equal - NotEqualsToken - // NotInToken represents not in - NotInToken - // OpenParToken represents open parenthesis - OpenParToken -) - -// string2token contains the mapping between lexer Token and token literal -// (except IdentifierToken, EndOfStringToken and ErrorToken since it makes no sense) -var string2token = map[string]Token{ - ")": ClosedParToken, - ",": CommaToken, - "!": DoesNotExistToken, - "==": DoubleEqualsToken, - "=": EqualsToken, - ">": GreaterThanToken, - "in": InToken, - "<": LessThanToken, - "!=": NotEqualsToken, - "notin": NotInToken, - "(": OpenParToken, -} - -// ScannedItem contains the Token and the literal produced by the lexer. -type ScannedItem struct { - tok Token - literal string -} - -// isWhitespace returns true if the rune is a space, tab, or newline. -func isWhitespace(ch byte) bool { - return ch == ' ' || ch == '\t' || ch == '\r' || ch == '\n' -} - -// isSpecialSymbol detects if the character ch can be an operator -func isSpecialSymbol(ch byte) bool { - switch ch { - case '=', '!', '(', ')', ',', '>', '<': - return true - } - return false -} - -// Lexer represents the Lexer struct for label selector. -// It contains necessary informationt to tokenize the input string -type Lexer struct { - // s stores the string to be tokenized - s string - // pos is the position currently tokenized - pos int -} - -// read returns the character currently lexed -// increment the position and check the buffer overflow -func (l *Lexer) read() (b byte) { - b = 0 - if l.pos < len(l.s) { - b = l.s[l.pos] - l.pos++ - } - return b -} - -// unread 'undoes' the last read character -func (l *Lexer) unread() { - l.pos-- -} - -// scanIDOrKeyword scans string to recognize literal token (for example 'in') or an identifier. -func (l *Lexer) scanIDOrKeyword() (tok Token, lit string) { - var buffer []byte -IdentifierLoop: - for { - switch ch := l.read(); { - case ch == 0: - break IdentifierLoop - case isSpecialSymbol(ch) || isWhitespace(ch): - l.unread() - break IdentifierLoop - default: - buffer = append(buffer, ch) - } - } - s := string(buffer) - if val, ok := string2token[s]; ok { // is a literal token? - return val, s - } - return IdentifierToken, s // otherwise is an identifier -} - -// scanSpecialSymbol scans string starting with special symbol. -// special symbol identify non literal operators. "!=", "==", "=" -func (l *Lexer) scanSpecialSymbol() (Token, string) { - lastScannedItem := ScannedItem{} - var buffer []byte -SpecialSymbolLoop: - for { - switch ch := l.read(); { - case ch == 0: - break SpecialSymbolLoop - case isSpecialSymbol(ch): - buffer = append(buffer, ch) - if token, ok := string2token[string(buffer)]; ok { - lastScannedItem = ScannedItem{tok: token, literal: string(buffer)} - } else if lastScannedItem.tok != 0 { - l.unread() - break SpecialSymbolLoop - } - default: - l.unread() - break SpecialSymbolLoop - } - } - if lastScannedItem.tok == 0 { - return ErrorToken, fmt.Sprintf("error expected: keyword found '%s'", buffer) - } - return lastScannedItem.tok, lastScannedItem.literal -} - -// skipWhiteSpaces consumes all blank characters -// returning the first non blank character -func (l *Lexer) skipWhiteSpaces(ch byte) byte { - for { - if !isWhitespace(ch) { - return ch - } - ch = l.read() - } -} - -// Lex returns a pair of Token and the literal -// literal is meaningfull only for IdentifierToken token -func (l *Lexer) Lex() (tok Token, lit string) { - switch ch := l.skipWhiteSpaces(l.read()); { - case ch == 0: - return EndOfStringToken, "" - case isSpecialSymbol(ch): - l.unread() - return l.scanSpecialSymbol() - default: - l.unread() - return l.scanIDOrKeyword() - } -} - -// Parser data structure contains the label selector parser data structure -type Parser struct { - l *Lexer - scannedItems []ScannedItem - position int - path *field.Path -} - -// ParserContext represents context during parsing: -// some literal for example 'in' and 'notin' can be -// recognized as operator for example 'x in (a)' but -// it can be recognized as value for example 'value in (in)' -type ParserContext int - -const ( - // KeyAndOperator represents key and operator - KeyAndOperator ParserContext = iota - // Values represents values - Values -) - -// lookahead func returns the current token and string. No increment of current position -func (p *Parser) lookahead(context ParserContext) (Token, string) { - tok, lit := p.scannedItems[p.position].tok, p.scannedItems[p.position].literal - if context == Values { - switch tok { - case InToken, NotInToken: - tok = IdentifierToken - } - } - return tok, lit -} - -// consume returns current token and string. Increments the position -func (p *Parser) consume(context ParserContext) (Token, string) { - p.position++ - tok, lit := p.scannedItems[p.position-1].tok, p.scannedItems[p.position-1].literal - if context == Values { - switch tok { - case InToken, NotInToken: - tok = IdentifierToken - } - } - return tok, lit -} - -// scan runs through the input string and stores the ScannedItem in an array -// Parser can now lookahead and consume the tokens -func (p *Parser) scan() { - for { - token, literal := p.l.Lex() - p.scannedItems = append(p.scannedItems, ScannedItem{token, literal}) - if token == EndOfStringToken { - break - } - } -} - -// parse runs the left recursive descending algorithm -// on input string. It returns a list of Requirement objects. -func (p *Parser) parse() (internalSelector, error) { - p.scan() // init scannedItems - - var requirements internalSelector - for { - tok, lit := p.lookahead(Values) - switch tok { - case IdentifierToken, DoesNotExistToken: - r, err := p.parseRequirement() - if err != nil { - return nil, fmt.Errorf("unable to parse requirement: %v", err) - } - requirements = append(requirements, *r) - t, l := p.consume(Values) - switch t { - case EndOfStringToken: - return requirements, nil - case CommaToken: - t2, l2 := p.lookahead(Values) - if t2 != IdentifierToken && t2 != DoesNotExistToken { - return nil, fmt.Errorf("found '%s', expected: identifier after ','", l2) - } - default: - return nil, fmt.Errorf("found '%s', expected: ',' or 'end of string'", l) - } - case EndOfStringToken: - return requirements, nil - default: - return nil, fmt.Errorf("found '%s', expected: !, identifier, or 'end of string'", lit) - } - } -} - -func (p *Parser) parseRequirement() (*Requirement, error) { - key, operator, err := p.parseKeyAndInferOperator() - if err != nil { - return nil, err - } - if operator == selection.Exists || operator == selection.DoesNotExist { // operator found lookahead set checked - return NewRequirement(key, operator, []string{}, field.WithPath(p.path)) - } - operator, err = p.parseOperator() - if err != nil { - return nil, err - } - var values sets.String - switch operator { - case selection.In, selection.NotIn: - values, err = p.parseValues() - case selection.Equals, selection.DoubleEquals, selection.NotEquals, selection.GreaterThan, selection.LessThan: - values, err = p.parseExactValue() - } - if err != nil { - return nil, err - } - return NewRequirement(key, operator, values.List(), field.WithPath(p.path)) - -} - -// parseKeyAndInferOperator parses literals. -// in case of no operator '!, in, notin, ==, =, !=' are found -// the 'exists' operator is inferred -func (p *Parser) parseKeyAndInferOperator() (string, selection.Operator, error) { - var operator selection.Operator - tok, literal := p.consume(Values) - if tok == DoesNotExistToken { - operator = selection.DoesNotExist - tok, literal = p.consume(Values) - } - if tok != IdentifierToken { - err := fmt.Errorf("found '%s', expected: identifier", literal) - return "", "", err - } - if err := validateLabelKey(literal, p.path); err != nil { - return "", "", err - } - if t, _ := p.lookahead(Values); t == EndOfStringToken || t == CommaToken { - if operator != selection.DoesNotExist { - operator = selection.Exists - } - } - return literal, operator, nil -} - -// parseOperator returns operator and eventually matchType -// matchType can be exact -func (p *Parser) parseOperator() (op selection.Operator, err error) { - tok, lit := p.consume(KeyAndOperator) - switch tok { - // DoesNotExistToken shouldn't be here because it's a unary operator, not a binary operator - case InToken: - op = selection.In - case EqualsToken: - op = selection.Equals - case DoubleEqualsToken: - op = selection.DoubleEquals - case GreaterThanToken: - op = selection.GreaterThan - case LessThanToken: - op = selection.LessThan - case NotInToken: - op = selection.NotIn - case NotEqualsToken: - op = selection.NotEquals - default: - return "", fmt.Errorf("found '%s', expected: %v", lit, strings.Join(binaryOperators, ", ")) - } - return op, nil -} - -// parseValues parses the values for set based matching (x,y,z) -func (p *Parser) parseValues() (sets.String, error) { - tok, lit := p.consume(Values) - if tok != OpenParToken { - return nil, fmt.Errorf("found '%s' expected: '('", lit) - } - tok, lit = p.lookahead(Values) - switch tok { - case IdentifierToken, CommaToken: - s, err := p.parseIdentifiersList() // handles general cases - if err != nil { - return s, err - } - if tok, _ = p.consume(Values); tok != ClosedParToken { - return nil, fmt.Errorf("found '%s', expected: ')'", lit) - } - return s, nil - case ClosedParToken: // handles "()" - p.consume(Values) - return sets.NewString(""), nil - default: - return nil, fmt.Errorf("found '%s', expected: ',', ')' or identifier", lit) - } -} - -// parseIdentifiersList parses a (possibly empty) list of -// of comma separated (possibly empty) identifiers -func (p *Parser) parseIdentifiersList() (sets.String, error) { - s := sets.NewString() - for { - tok, lit := p.consume(Values) - switch tok { - case IdentifierToken: - s.Insert(lit) - tok2, lit2 := p.lookahead(Values) - switch tok2 { - case CommaToken: - continue - case ClosedParToken: - return s, nil - default: - return nil, fmt.Errorf("found '%s', expected: ',' or ')'", lit2) - } - case CommaToken: // handled here since we can have "(," - if s.Len() == 0 { - s.Insert("") // to handle (, - } - tok2, _ := p.lookahead(Values) - if tok2 == ClosedParToken { - s.Insert("") // to handle ,) Double "" removed by StringSet - return s, nil - } - if tok2 == CommaToken { - p.consume(Values) - s.Insert("") // to handle ,, Double "" removed by StringSet - } - default: // it can be operator - return s, fmt.Errorf("found '%s', expected: ',', or identifier", lit) - } - } -} - -// parseExactValue parses the only value for exact match style -func (p *Parser) parseExactValue() (sets.String, error) { - s := sets.NewString() - tok, _ := p.lookahead(Values) - if tok == EndOfStringToken || tok == CommaToken { - s.Insert("") - return s, nil - } - tok, lit := p.consume(Values) - if tok == IdentifierToken { - s.Insert(lit) - return s, nil - } - return nil, fmt.Errorf("found '%s', expected: identifier", lit) -} - -// Parse takes a string representing a selector and returns a selector -// object, or an error. This parsing function differs from ParseSelector -// as they parse different selectors with different syntaxes. -// The input will cause an error if it does not follow this form: -// -// <selector-syntax> ::= <requirement> | <requirement> "," <selector-syntax> -// <requirement> ::= [!] KEY [ <set-based-restriction> | <exact-match-restriction> ] -// <set-based-restriction> ::= "" | <inclusion-exclusion> <value-set> -// <inclusion-exclusion> ::= <inclusion> | <exclusion> -// <exclusion> ::= "notin" -// <inclusion> ::= "in" -// <value-set> ::= "(" <values> ")" -// <values> ::= VALUE | VALUE "," <values> -// <exact-match-restriction> ::= ["="|"=="|"!="] VALUE -// -// KEY is a sequence of one or more characters following [ DNS_SUBDOMAIN "/" ] DNS_LABEL. Max length is 63 characters. -// VALUE is a sequence of zero or more characters "([A-Za-z0-9_-\.])". Max length is 63 characters. -// Delimiter is white space: (' ', '\t') -// Example of valid syntax: -// "x in (foo,,baz),y,z notin ()" -// -// Note: -// (1) Inclusion - " in " - denotes that the KEY exists and is equal to any of the -// VALUEs in its requirement -// (2) Exclusion - " notin " - denotes that the KEY is not equal to any -// of the VALUEs in its requirement or does not exist -// (3) The empty string is a valid VALUE -// (4) A requirement with just a KEY - as in "y" above - denotes that -// the KEY exists and can be any VALUE. -// (5) A requirement with just !KEY requires that the KEY not exist. -// -func Parse(selector string, opts ...field.PathOption) (Selector, error) { - parsedSelector, err := parse(selector, field.ToPath(opts...)) - if err == nil { - return parsedSelector, nil - } - return nil, err -} - -// parse parses the string representation of the selector and returns the internalSelector struct. -// The callers of this method can then decide how to return the internalSelector struct to their -// callers. This function has two callers now, one returns a Selector interface and the other -// returns a list of requirements. -func parse(selector string, path *field.Path) (internalSelector, error) { - p := &Parser{l: &Lexer{s: selector, pos: 0}, path: path} - items, err := p.parse() - if err != nil { - return nil, err - } - sort.Sort(ByKey(items)) // sort to grant determistic parsing - return internalSelector(items), err -} - -func validateLabelKey(k string, path *field.Path) *field.Error { - if errs := validation.IsQualifiedName(k); len(errs) != 0 { - return field.Invalid(path, k, strings.Join(errs, "; ")) - } - return nil -} - -func validateLabelValue(k, v string, path *field.Path) *field.Error { - if errs := validation.IsValidLabelValue(v); len(errs) != 0 { - return field.Invalid(path.Key(k), v, strings.Join(errs, "; ")) - } - return nil -} - -// SelectorFromSet returns a Selector which will match exactly the given Set. A -// nil and empty Sets are considered equivalent to Everything(). -// It does not perform any validation, which means the server will reject -// the request if the Set contains invalid values. -func SelectorFromSet(ls Set) Selector { - return SelectorFromValidatedSet(ls) -} - -// ValidatedSelectorFromSet returns a Selector which will match exactly the given Set. A -// nil and empty Sets are considered equivalent to Everything(). -// The Set is validated client-side, which allows to catch errors early. -func ValidatedSelectorFromSet(ls Set) (Selector, error) { - if ls == nil || len(ls) == 0 { - return internalSelector{}, nil - } - requirements := make([]Requirement, 0, len(ls)) - for label, value := range ls { - r, err := NewRequirement(label, selection.Equals, []string{value}) - if err != nil { - return nil, err - } - requirements = append(requirements, *r) - } - // sort to have deterministic string representation - sort.Sort(ByKey(requirements)) - return internalSelector(requirements), nil -} - -// SelectorFromValidatedSet returns a Selector which will match exactly the given Set. -// A nil and empty Sets are considered equivalent to Everything(). -// It assumes that Set is already validated and doesn't do any validation. -func SelectorFromValidatedSet(ls Set) Selector { - if ls == nil || len(ls) == 0 { - return internalSelector{} - } - requirements := make([]Requirement, 0, len(ls)) - for label, value := range ls { - requirements = append(requirements, Requirement{key: label, operator: selection.Equals, strValues: []string{value}}) - } - // sort to have deterministic string representation - sort.Sort(ByKey(requirements)) - return internalSelector(requirements) -} - -// ParseToRequirements takes a string representing a selector and returns a list of -// requirements. This function is suitable for those callers that perform additional -// processing on selector requirements. -// See the documentation for Parse() function for more details. -// TODO: Consider exporting the internalSelector type instead. -func ParseToRequirements(selector string, opts ...field.PathOption) ([]Requirement, error) { - return parse(selector, field.ToPath(opts...)) -} |