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package query

import "github.com/tendermint/tendermint/libs/pubsub/query"

Package query provides a parser for a custom query format:

abci.invoice.number=22 AND abci.invoice.owner=Ivan

See query.peg for the grammar, which is a https://en.wikipedia.org/wiki/Parsing_expression_grammar. More: https://github.com/PhilippeSigaud/Pegged/wiki/PEG-Basics

It has a support for numbers (integer and floating point), dates and times.



Package Files

empty.go peg.go query.go query.peg.go


const (
    // DateLayout defines a layout for all dates (`DATE date`)
    DateLayout = "2006-01-02"
    // TimeLayout defines a layout for all times (`TIME time`)
    TimeLayout = time.RFC3339

type Condition Uses

type Condition struct {
    CompositeKey string
    Op           Operator
    Operand      interface{}

Condition represents a single condition within a query and consists of composite key (e.g. "tx.gas"), operator (e.g. "=") and operand (e.g. "7").

type Empty Uses

type Empty struct {

Empty query matches any set of events.

func (Empty) Matches Uses

func (Empty) Matches(tags map[string][]string) (bool, error)

Matches always returns true.

func (Empty) String Uses

func (Empty) String() string

type Operator Uses

type Operator uint8

Operator is an operator that defines some kind of relation between composite key and operand (equality, etc.).

const (
    // "<="
    OpLessEqual Operator = iota
    // ">="
    // "<"
    // ">"
    // "="
    // "CONTAINS"; used to check if a string contains a certain sub string.
    // "EXISTS"; used to check if a certain event attribute is present.

type Query Uses

type Query struct {
    // contains filtered or unexported fields

Query holds the query string and the query parser.

func MustParse Uses

func MustParse(s string) *Query

MustParse turns the given string into a query or panics; for tests or others cases where you know the string is valid.

func New Uses

func New(s string) (*Query, error)

New parses the given string and returns a query or error if the string is invalid.

func (*Query) Conditions Uses

func (q *Query) Conditions() ([]Condition, error)

Conditions returns a list of conditions. It returns an error if there is any error with the provided grammar in the Query.

func (*Query) Matches Uses

func (q *Query) Matches(events map[string][]string) (bool, error)

Matches returns true if the query matches against any event in the given set of events, false otherwise. For each event, a match exists if the query is matched against *any* value in a slice of values. An error is returned if any attempted event match returns an error.

For example, query "name=John" matches events = {"name": ["John", "Eric"]}. More examples could be found in parser_test.go and query_test.go.

func (*Query) String Uses

func (q *Query) String() string

String returns the original string.

type QueryParser Uses

type QueryParser struct {
    Buffer string

    Parse  func(rule ...int) error
    Reset  func()
    Pretty bool
    // contains filtered or unexported fields

func (*QueryParser) AST Uses

func (t *QueryParser) AST() *node32

func (*QueryParser) Add Uses

func (t *QueryParser) Add(rule pegRule, begin, end, depth uint32, index int)

func (*QueryParser) Error Uses

func (t *QueryParser) Error() []token32

func (*QueryParser) Expand Uses

func (t *QueryParser) Expand(index int)

func (*QueryParser) Highlighter Uses

func (p *QueryParser) Highlighter()

func (*QueryParser) Init Uses

func (p *QueryParser) Init()

func (*QueryParser) Order Uses

func (t *QueryParser) Order() [][]token32

func (*QueryParser) PreOrder Uses

func (t *QueryParser) PreOrder() (<-chan state32, [][]token32)

func (*QueryParser) Print Uses

func (t *QueryParser) Print()

func (*QueryParser) PrintSyntax Uses

func (t *QueryParser) PrintSyntax()

func (*QueryParser) PrintSyntaxTree Uses

func (p *QueryParser) PrintSyntaxTree()

func (*QueryParser) Tokens Uses

func (t *QueryParser) Tokens() <-chan token32



Package query imports 8 packages (graph) and is imported by 43 packages. Updated 2020-05-13. Refresh now. Tools for package owners.