authPostman/internal/postman.go

package postman

import (
	"context"
	"log"
	"net"
	"strconv"
	"test3k/authPostman/internal/config"

	"github.com/segmentio/kafka-go"
)

type AuthPostmanServer struct {
	kafkaReader *kafka.Reader
	ctx         context.Context
}

func NewServer(ctx context.Context, config *config.Config, topic string) *AuthPostmanServer {
	return &AuthPostmanServer{
		kafkaReader: kafka.NewReader(kafka.ReaderConfig{
			Topic:     topic,
			Brokers:   []string{net.JoinHostPort(config.Kafka.Host, strconv.Itoa(config.Kafka.Port))},
			GroupID:   "consumer-group-id",
			Partition: 0,
			MinBytes:  10e3, // 10KB
			MaxBytes:  10e6, // 10MB
		}),
		ctx: ctx,
	}
}

func (s *AuthPostmanServer) GracefulStop() error {
	return s.kafkaReader.Close()
}

func (s *AuthPostmanServer) ReadMessage(offset int64) error {
	// ...
	s.kafkaReader.SetOffset(offset)

	//
	for {
		m, err := s.kafkaReader.ReadMessage(s.ctx)
		if err != nil {
			return err
		}

		log.Printf("message at offset %d: %s = %s\n", m.Offset, string(m.Key), string(m.Value))
	}
}