tixel-elastic: initial commit with first prototype version for discussion

elasticsearch.go

@@ -0,0 +1,148 @@
+package main
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"log/slog"
+	"strings"
+	"time"
+
+	"github.com/elastic/go-elasticsearch/v7"
+)
+
+func NewElasticsearchClient(config ElasticsearchConfig) (*elasticsearch.Client, error) {
+	esConfig := elasticsearch.Config{
+		Addresses: []string{config.URL},
+	}
+
+	if config.Username != "" && config.Password != "" {
+		esConfig.Username = config.Username
+		esConfig.Password = config.Password
+	}
+
+	client, err := elasticsearch.NewClient(esConfig)
+	if err != nil {
+		return nil, fmt.Errorf("failed to create elasticsearch client: %w", err)
+	}
+
+	return client, nil
+}
+
+func TestElasticsearchConnection(es *elasticsearch.Client) error {
+	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
+	defer cancel()
+
+	res, err := es.Info(es.Info.WithContext(ctx))
+	if err != nil {
+		return fmt.Errorf("connection test failed: %w", err)
+	}
+	defer res.Body.Close()
+
+	if res.IsError() {
+		return fmt.Errorf("connection test failed: %s", res.String())
+	}
+
+	return nil
+}
+
+type ElasticsearchSender interface {
+	SendBatch(baseIndex string, entries []LogEntry) error
+	SendSystemMetrics(baseIndex string, metrics SystemResources) error
+}
+
+type ElasticsearchClient struct {
+	client *elasticsearch.Client
+}
+
+func NewElasticsearchSender(client *elasticsearch.Client) ElasticsearchSender {
+	return &ElasticsearchClient{client: client}
+}
+
+func (esc *ElasticsearchClient) SendBatch(baseIndex string, entries []LogEntry) error {
+	if len(entries) == 0 {
+		return nil
+	}
+
+	var body strings.Builder
+	for _, entry := range entries {
+		indexName := determineIndexName(baseIndex, entry)
+
+		indexLine := fmt.Sprintf(`{"index":{"_index":"%s"}}`, indexName)
+		body.WriteString(indexLine)
+		body.WriteString("\n")
+
+		data, err := json.Marshal(entry)
+		if err != nil {
+			slog.Error("error marshalling JSON", "error", err)
+			continue
+		}
+		body.WriteString(string(data))
+		body.WriteString("\n")
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
+	defer cancel()
+
+	res, err := esc.client.Bulk(
+		strings.NewReader(body.String()),
+		esc.client.Bulk.WithContext(ctx),
+	)
+	if err != nil {
+		return fmt.Errorf("bulk request error: %w", err)
+	}
+	defer res.Body.Close()
+
+	if res.IsError() {
+		return fmt.Errorf("bulk request failed: %s", res.String())
+	}
+
+	slog.Debug("Batch successfully sent", "count", len(entries))
+	return nil
+}
+
+func (esc *ElasticsearchClient) SendSystemMetrics(baseIndex string, metrics SystemResources) error {
+	data, err := json.Marshal(metrics)
+	if err != nil {
+		return fmt.Errorf("JSON marshalling error: %w", err)
+	}
+
+	systemIndex := fmt.Sprintf("%s-system", baseIndex)
+
+	ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
+	defer cancel()
+
+	res, err := esc.client.Index(
+		systemIndex,
+		strings.NewReader(string(data)),
+		esc.client.Index.WithContext(ctx),
+	)
+	if err != nil {
+		return fmt.Errorf("elasticsearch index error: %w", err)
+	}
+	defer res.Body.Close()
+
+	if res.IsError() {
+		return fmt.Errorf("elasticsearch error: %s", res.String())
+	}
+
+	slog.Debug("System-Metrics sent",
+		"CPU", metrics.CPUPercent,
+		"MEM_used", metrics.MemoryUsed,
+		"MEM_total", metrics.MemoryTotal,
+		"MEM_percentage", metrics.MemoryPercent,
+	)
+
+	return nil
+}
+
+func determineIndexName(baseIndex string, entry LogEntry) string {
+	switch entry.Type {
+	case "system_metrics":
+		return fmt.Sprintf("%s-system", baseIndex)
+	case "service_log":
+		return fmt.Sprintf("%s-service-%s", baseIndex, entry.Service)
+	default:
+		return fmt.Sprintf("%s-%s", baseIndex, entry.Tool)
+	}
+}