feat(log): Adding colored output for error or warning level

Signed-off-by: Vincent Boutour <[email protected]>

README.md

@@ -82,8 +82,10 @@ Flags:
   -d, --dry-run                   Dry-run, print only pods
   -g, --grep string               Regexp to filter log
   -h, --help                      help for log
+      --levelKey string           Key for level in JSON (default "level")
   -l, --selector stringToString   Labels to filter pods (default [])
   -s, --since duration            Display logs since given duration (default 1h0m0s)
+      --statusCodeKey string      Key for HTTP Status code in JSON (default "statusCode")
 ```
 
 ### `port-forward`

cmd/log.go

@@ -33,6 +33,9 @@ var (
 	containersName   []string
 	containersRegexp []*regexp.Regexp
 
+	levelKey      string
+	statusCodeKey string
+
 	logFilter       string
 	logFilterRegexp *regexp.Regexp
 )
@@ -165,6 +168,8 @@ func initLog() {
 	flags.BoolVarP(&dryRun, "dry-run", "d", false, "Dry-run, print only pods")
 	flags.StringToStringVarP(&labelsSelector, "selector", "l", nil, "Labels to filter pods")
 	flags.StringVarP(&logFilter, "grep", "g", "", "Regexp to filter log")
+	flags.StringVar(&levelKey, "levelKey", "level", "Key for level in JSON")
+	flags.StringVar(&statusCodeKey, "statusCodeKey", "statusCode", "Key for HTTP Status code in JSON")
 }
 
 func handleLogPod(ctx context.Context, activeStreams *sync.Map, streaming *concurrent.Simple, kube client.Kube, pod v1.Pod) {
@@ -238,13 +243,18 @@ func outputLog(reader io.Reader, kube client.Kube, name, container string) {
 	streamScanner.Split(bufio.ScanLines)
 
 	for streamScanner.Scan() {
+		text := streamScanner.Text()
+
+		if colorOutputter := getColorFromJSON(strings.NewReader(text), levelKey, statusCodeKey); colorOutputter != nil {
+			text = colorOutputter(text)
+		}
+
 		if logFilterRegexp == nil {
-			outputter.Std(streamScanner.Text())
+			outputter.Std(text)
+
 			continue
 		}
 
-		text := streamScanner.Text()
-
 		if !logFilterRegexp.MatchString(text) {
 			continue
 		}

cmd/log_color.go

@@ -0,0 +1,90 @@
+package cmd
+
+import (
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"strings"
+
+	"github.com/ViBiOh/kmux/pkg/output"
+)
+
+type Formatter func(a ...interface{}) string
+
+func getColorFromJSON(stream io.Reader, keys ...string) Formatter {
+	decoder := json.NewDecoder(stream)
+
+	if err := moveDecoderToKey(decoder, keys...); err != nil {
+		return nil
+	}
+
+	token, err := decoder.Token()
+	if err != nil {
+		return nil
+	}
+
+	switch value := token.(type) {
+	case string:
+		switch strings.ToLower(value) {
+		case "warn", "warning":
+			return output.Yellow
+		case "error", "critical", "fatal":
+			return output.Red
+		case "trace", "debug":
+			return output.Green
+		default:
+			return nil
+		}
+	case float64:
+		switch {
+		case value >= http.StatusInternalServerError:
+			return output.Red
+		case value >= http.StatusBadRequest:
+			return output.Yellow
+		case value >= http.StatusMultipleChoices:
+			return output.Green
+		default:
+			return nil
+		}
+	default:
+		return nil
+	}
+}
+
+func moveDecoderToKey(decoder *json.Decoder, keys ...string) error {
+	var token json.Token
+	var nested uint64
+	var err error
+
+	for {
+		token, err = decoder.Token()
+		if err != nil {
+			return fmt.Errorf("decode token: %w", err)
+		}
+
+		if nested == 1 {
+			tokenStr := fmt.Sprintf("%s", token)
+			var found bool
+
+			for _, key := range keys {
+				if strings.EqualFold(tokenStr, key) {
+					found = true
+					break
+				}
+			}
+
+			if found {
+				break
+			}
+		}
+
+		if strToken := fmt.Sprintf("%s", token); strToken == "{" {
+			nested++
+		} else if strToken == "}" {
+			nested--
+		}
+	}
+
+	return nil
+}