loki/pkg/engine/internal/planner/logical/node_parse.go

package logical

import (
	"fmt"

	"github.com/grafana/loki/v3/pkg/engine/internal/planner/schema"
)

// ParserKind represents the type of parser to use
type ParserKind int

const (
	ParserInvalid ParserKind = iota
	ParserLogfmt
	ParserJSON
)

func (p ParserKind) String() string {
	switch p {
	case ParserLogfmt:
		return "logfmt"
	case ParserJSON:
		return "json"
	default:
		return "invalid"
	}
}

// Parse represents a parsing instruction that extracts fields from log lines.
// It takes a table relation as input and produces a new table relation with
// additional columns for the parsed fields.
type Parse struct {
	id string

	Table Value // The table relation to parse from
	Kind  ParserKind
}

// Name returns an identifier for the Parse operation.
func (p *Parse) Name() string {
	if p.id != "" {
		return p.id
	}
	return fmt.Sprintf("%p", p)
}

// String returns the string representation of the Parse instruction
func (p *Parse) String() string {
	return fmt.Sprintf("PARSE %s [kind=%v]", p.Table.Name(), p.Kind)
}

// Schema returns the schema of the Parse operation.
func (p *Parse) Schema() *schema.Schema {
	return p.Table.Schema()
}

// isInstruction marks Parse as an Instruction
func (p *Parse) isInstruction() {}

// isValue marks Parse as a Value
func (p *Parse) isValue() {}