log stuff added

go.mod

@@ -1,3 +1,11 @@
 module oc-lib
 
 go 1.22.0
+
+require github.com/rs/zerolog v1.33.0
+
+require (
+	github.com/mattn/go-colorable v0.1.13 // indirect
+	github.com/mattn/go-isatty v0.0.19 // indirect
+	golang.org/x/sys v0.12.0 // indirect
+)

go.sum

@@ -0,0 +1,15 @@
+github.com/coreos/go-systemd/v22 v22.5.0/go.mod h1:Y58oyj3AT4RCenI/lSvhwexgC+NSVTIJ3seZv2GcEnc=
+github.com/godbus/dbus/v5 v5.0.4/go.mod h1:xhWf0FNVPg57R7Z0UbKHbJfkEywrmjJnf7w5xrFpKfA=
+github.com/mattn/go-colorable v0.1.13 h1:fFA4WZxdEF4tXPZVKMLwD8oUnCTTo08duU7wxecdEvA=
+github.com/mattn/go-colorable v0.1.13/go.mod h1:7S9/ev0klgBDR4GtXTXX8a3vIGJpMovkB8vQcUbaXHg=
+github.com/mattn/go-isatty v0.0.16/go.mod h1:kYGgaQfpe5nmfYZH+SKPsOc2e4SrIfOl2e/yFXSvRLM=
+github.com/mattn/go-isatty v0.0.19 h1:JITubQf0MOLdlGRuRq+jtsDlekdYPia9ZFsB8h/APPA=
+github.com/mattn/go-isatty v0.0.19/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
+github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
+github.com/rs/xid v1.5.0/go.mod h1:trrq9SKmegXys3aeAKXMUTdJsYXVwGY3RLcfgqegfbg=
+github.com/rs/zerolog v1.33.0 h1:1cU2KZkvPxNyfgEmhHAz/1A9Bz+llsdYzklWFzgp0r8=
+github.com/rs/zerolog v1.33.0/go.mod h1:/7mN4D5sKwJLZQ2b/znpjC3/GQWY/xaDXUM0kKWRHss=
+golang.org/x/sys v0.0.0-20220811171246-fbc7d0a398ab/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.12.0 h1:CM0HF96J0hcLAwsHPJZjfdNzs0gftsLfgKt57wWHJ0o=
+golang.org/x/sys v0.12.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=

logger.go

@@ -0,0 +1,41 @@
+package oclib
+
+import (
+	"oc-lib/logs"
+	"os"
+	"runtime"
+	"time"
+
+	"github.com/rs/zerolog"
+)
+
+var logger zerolog.Logger
+
+// CreateLogger
+// Create a new logger
+// Parameters:
+// - appname: string : the name of the application using oclib
+// - url: string : the url of a loki logger, console log only if ""
+// Returns:
+// - zerolog.Logger : the logger that will log for the library and the app
+func CreateLogger(appname string, url string) zerolog.Logger {
+
+	if url != "" {
+		labels := map[string]string{
+			"app":      "app",
+			"code":     "go",
+			"platform": runtime.GOOS,
+		}
+
+		lokiWriter := logs.NewLokiWriter(url, labels)
+
+		consoleWriter := zerolog.ConsoleWriter{Out: os.Stdout, TimeFormat: time.RFC3339}
+
+		multiWriter := zerolog.MultiLevelWriter(consoleWriter, lokiWriter)
+
+		logger = zerolog.New(multiWriter).With().Timestamp().Logger()
+	} else {
+		logger = zerolog.New(os.Stdout).With().Timestamp().Logger()
+	}
+	return logger
+}

logs/lokiwriter.go

@@ -0,0 +1,97 @@
+package logs
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"time"
+)
+
+type LokiWriter struct {
+	url        string
+	labels     map[string]string
+	httpClient *http.Client
+}
+
+type LokiPayload struct {
+	Streams []LokiStream `json:"streams"`
+}
+
+type LokiStream struct {
+	Stream map[string]string `json:"stream"`
+	Values [][]string        `json:"values"`
+}
+
+func NewLokiWriter(url string, labels map[string]string) *LokiWriter {
+	return &LokiWriter{
+		url:        url,
+		labels:     labels,
+		httpClient: &http.Client{},
+	}
+}
+
+func (w *LokiWriter) Write(p []byte) (n int, err error) {
+	// Use zerolog to parse the log level
+	var event map[string]interface{}
+	if err := json.Unmarshal(p, &event); err != nil {
+		return 0, fmt.Errorf("failed to unmarshal log event: %w", err)
+	}
+
+	level := ""
+	if l, ok := event["level"].(string); ok {
+		level = l
+	}
+
+	message := ""
+	if m, ok := event["message"].(string); ok {
+		message = m
+	}
+
+	// Add log level to labels
+	labels := make(map[string]string)
+	for k, v := range w.labels {
+		labels[k] = v
+	}
+	labels["level"] = level
+
+	// Format the timestamp in nanoseconds
+	timestamp := fmt.Sprintf("%d000000", time.Now().UnixNano()/int64(time.Millisecond))
+
+	stream := LokiStream{
+		Stream: labels,
+		Values: [][]string{
+			{timestamp, message},
+		},
+	}
+
+	payload := LokiPayload{
+		Streams: []LokiStream{stream},
+	}
+
+	payloadBytes, err := json.Marshal(payload)
+	if err != nil {
+		return 0, fmt.Errorf("failed to marshal payload: %w", err)
+	}
+
+	//fmt.Printf("Sending payload to Loki: %s\n", string(payloadBytes))
+
+	req, err := http.NewRequest("POST", w.url, bytes.NewReader(payloadBytes))
+	if err != nil {
+		return 0, fmt.Errorf("failed to create HTTP request: %w", err)
+	}
+	req.Header.Set("Content-Type", "application/json")
+
+	resp, err := w.httpClient.Do(req)
+	if err != nil {
+		return 0, fmt.Errorf("failed to send log to Loki: %w", err)
+	}
+	defer resp.Body.Close()
+
+	//fmt.Printf("Loki response status: %d\n", resp.StatusCode)
+	if resp.StatusCode != http.StatusNoContent {
+		return 0, fmt.Errorf("received non-204 response from Loki: %d", resp.StatusCode)
+	}
+
+	return len(p), nil
+}