GMC: enhance log (#371)

* enhance log

Signed-off-by: KfreeZ <[email protected]>

* enhance log

Signed-off-by: KfreeZ <[email protected]>

* add debug level classifier

Signed-off-by: KfreeZ <[email protected]>

* add debug level classifier

Signed-off-by: KfreeZ <[email protected]>

* add dynamic change log level

Signed-off-by: KfreeZ <[email protected]>

* re-trigger e2e

Signed-off-by: KfreeZ <[email protected]>

* add validatation of http requests

Signed-off-by: KfreeZ <[email protected]>

* update doc for log control

Signed-off-by: KfreeZ <[email protected]>

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

---------

Signed-off-by: KfreeZ <[email protected]>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

Author: KfreeZ

microservices-connector/cmd/main.go

@@ -7,9 +7,15 @@ package main
 
 import (
 	"crypto/tls"
+	"encoding/json"
 	"flag"
+	"fmt"
+	"net/http"
 	"os"
 
+	uzap "go.uber.org/zap"
+	"go.uber.org/zap/zapcore"
+
 	// Import all Kubernetes client auth plugins (e.g. Azure, GCP, OIDC, etc.)
 	// to ensure that exec-entrypoint and run can make use of them.
 	_ "k8s.io/client-go/plugin/pkg/client/auth"
@@ -46,6 +52,43 @@ func init() {
 	//+kubebuilder:scaffold:scheme
 }
 
+func logLevelHandler(atomicLevel uzap.AtomicLevel) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		switch r.Method {
+		case http.MethodGet:
+			// Return the current log level
+			currentLevel := atomicLevel.Level()
+			fmt.Fprintf(w, "current log level: %s\n", currentLevel.String())
+		case http.MethodPut:
+			// Change the log level
+			var reqBody struct {
+				LogLevel string `json:"log_level"`
+			}
+			if err := json.NewDecoder(r.Body).Decode(&reqBody); err != nil {
+				http.Error(w, fmt.Sprintf("invalid request body: %v\n", err), http.StatusBadRequest)
+				return
+			} else {
+				if reqBody.LogLevel == "" {
+					http.Error(w, "log_level field is required\n", http.StatusBadRequest)
+					return
+				}
+			}
+			var zapLevel zapcore.Level
+			if err := zapLevel.UnmarshalText([]byte(reqBody.LogLevel)); err != nil {
+				http.Error(w, fmt.Sprintf("invalid log level: %v\n", err), http.StatusBadRequest)
+				return
+			}
+			atomicLevel.SetLevel(zapLevel)
+			fmt.Fprintf(w, "log level set to %s\n", zapLevel.String())
+			setupLog.V(1).Info("1 log level set to ", "level", zapLevel.String())
+			setupLog.V(2).Info("2 log level set to ", "level", zapLevel.String())
+			setupLog.Info("log level set to ", "level", zapLevel.String())
+		default:
+			http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
+		}
+	}
+}
+
 func main() {
 	var metricsAddr string
 	var enableLeaderElection bool
@@ -61,14 +104,27 @@ func main() {
 		"If set the metrics endpoint is served securely")
 	flag.BoolVar(&enableHTTP2, "enable-http2", false,
 		"If set, HTTP/2 will be enabled for the metrics and webhook servers")
+	atomicLevel := uzap.NewAtomicLevel()
+	atomicLevel.SetLevel(zapcore.InfoLevel) // Set initial log level
 	opts := zap.Options{
 		Development: true,
+		Level:       atomicLevel,
 	}
 	opts.BindFlags(flag.CommandLine)
 	flag.Parse()
 
 	ctrl.SetLogger(zap.New(zap.UseFlagOptions(&opts)))
 
+	// Set up an HTTP server to change the log level dynamically
+	http.HandleFunc("/loglevel", logLevelHandler(atomicLevel))
+
+	// Start the HTTP server
+	go func() {
+		if err := http.ListenAndServe(":8008", nil); err != nil {
+			setupLog.Error(err, "HTTP server failed")
+		}
+	}()
+
 	// if the enable-http2 flag is false (the default), http/2 should be disabled
 	// due to its vulnerabilities. More specifically, disabling http/2 will
 	// prevent from being vulnerable to the HTTP/2 Stream Cancellation and