1 files changed, 76 insertions, 0 deletions
diff --git a/src/go/collectors/go.d.plugin/pkg/logs/regexp.go b/src/go/collectors/go.d.plugin/pkg/logs/regexp.go
new file mode 100644
index 000000000..e0dee1d02
--- /dev/null
+++ b/src/go/collectors/go.d.plugin/pkg/logs/regexp.go
@@ -0,0 +1,76 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+package logs
+
+import (
+	"bufio"
+	"errors"
+	"fmt"
+	"io"
+	"regexp"
+)
+
+type (
+	RegExpConfig struct {
+		Pattern string `yaml:"pattern" json:"pattern"`
+	}
+
+	RegExpParser struct {
+		r       *bufio.Reader
+		pattern *regexp.Regexp
+	}
+)
+
+func NewRegExpParser(config RegExpConfig, in io.Reader) (*RegExpParser, error) {
+	if config.Pattern == "" {
+		return nil, errors.New("empty pattern")
+	}
+
+	pattern, err := regexp.Compile(config.Pattern)
+	if err != nil {
+		return nil, fmt.Errorf("compile: %w", err)
+	}
+
+	if pattern.NumSubexp() == 0 {
+		return nil, errors.New("pattern has no named subgroups")
+	}
+
+	p := &RegExpParser{
+		r:       bufio.NewReader(in),
+		pattern: pattern,
+	}
+	return p, nil
+}
+
+func (p *RegExpParser) ReadLine(line LogLine) error {
+	row, err := p.r.ReadSlice('\n')
+	if err != nil && len(row) == 0 {
+		return err
+	}
+	if len(row) > 0 && row[len(row)-1] == '\n' {
+		row = row[:len(row)-1]
+	}
+	return p.Parse(row, line)
+}
+
+func (p *RegExpParser) Parse(row []byte, line LogLine) error {
+	match := p.pattern.FindSubmatch(row)
+	if len(match) == 0 {
+		return &ParseError{msg: "regexp parse: unmatched line"}
+	}
+
+	for i, name := range p.pattern.SubexpNames() {
+		if name == "" || match[i] == nil {
+			continue
+		}
+		err := line.Assign(name, string(match[i]))
+		if err != nil {
+			return &ParseError{msg: fmt.Sprintf("regexp parse: %v", err), err: err}
+		}
+	}
+	return nil
+}
+
+func (p RegExpParser) Info() string {
+	return fmt.Sprintf("regexp: %s", p.pattern)
+}