Use common httpserver across fission (#2409)

* Defining httpserver package to capture httpserver shutdown and
introduces uniform running of http server across codebase.
* Add unit tests for httpserver

Signed-off-by: Sanket Sudake <sanketsudake@gmail.com>

pkg/executor/api.go

@@ -34,6 +34,7 @@ import (
 	fv1 "github.com/fission/fission/pkg/apis/core/v1"
 	ferror "github.com/fission/fission/pkg/error"
 	"github.com/fission/fission/pkg/executor/client"
+	"github.com/fission/fission/pkg/utils/httpserver"
 	"github.com/fission/fission/pkg/utils/metrics"
 	otelUtils "github.com/fission/fission/pkg/utils/otel"
 )
@@ -262,10 +263,7 @@ func (executor *Executor) GetHandler() http.Handler {
 }
 
 // Serve starts an HTTP server.
-func (executor *Executor) Serve(port int, openTracingEnabled bool) {
-	executor.logger.Info("starting executor API", zap.Int("port", port))
-	address := fmt.Sprintf(":%v", port)
-
+func (executor *Executor) Serve(ctx context.Context, port int, openTracingEnabled bool) {
 	var handler http.Handler
 	if openTracingEnabled {
 		handler = &ochttp.Handler{Handler: executor.GetHandler()}
@@ -273,6 +271,6 @@ func (executor *Executor) Serve(port int, openTracingEnabled bool) {
 		handler = otelUtils.GetHandlerWithOTEL(executor.GetHandler(), "fission-executor", otelUtils.UrlsToIgnore("/healthz"))
 	}
 
-	err := http.ListenAndServe(address, handler)
-	executor.logger.Fatal("done listening", zap.Error(err))
+	httpserver.StartServer(ctx, executor.logger, "executor", fmt.Sprintf("%d", port), handler)
+
 }

pkg/executor/executor.go

@@ -370,7 +370,7 @@ func StartExecutor(ctx context.Context, logger *zap.Logger, functionNamespace st
 	}
 	go reaper.CleanupRoleBindings(ctx, logger, kubernetesClient, fissionClient, functionNamespace, envBuilderNamespace, time.Minute*30)
 	go metrics.ServeMetrics(ctx, logger)
-	go api.Serve(port, openTracingEnabled)
+	go api.Serve(ctx, port, openTracingEnabled)
 
 	return nil
 }